1
|
Zhou G, Liu Y, Dong P, Mao Y, Zhu L, Luo X, Zhang Y. Airborne signals of Pseudomonas fluorescens modulate swimming motility and biofilm formation of Listeria monocytogenes in a contactless coculture system. Food Microbiol 2024; 120:104494. [PMID: 38431335 DOI: 10.1016/j.fm.2024.104494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 02/11/2024] [Accepted: 02/14/2024] [Indexed: 03/05/2024]
Abstract
Bacterial volatile compounds (BVCs) facilitate interspecies communication in socio-microbiology across physical barriers, thereby influencing interactions between diverse species. The impact of BVCs emitted from Pseudomonas on the biofilm formation characteristics of Listeria monocytogenes within the same ecological niche has been scarcely investigated under practical conditions of food processing. The objective of this study was to explore the motility and biofilm formation characteristics of L. monocytogenes under the impact of Pseudomonas BVCs. It was revealed that BVCs of P. fluorescens, P. lundensis, and P. fragi significantly promoted swimming motility of L. monocytogenes (P < 0.05). As evidenced by crystal violet staining, the L. monocytogenes biofilms reached a maximum OD570 value of approximately 3.78 at 4 d, which was 0.65 units markedly higher than that of the control group (P < 0.05). Despite a decrease in adherent cells of L. monocytogenes biofilms among the BVCs groups, there was a remarkable increase in the abundance of extracellular polysaccharides and proteins with 3.58 and 4.90 μg/cm2, respectively (P < 0.05), contributing to more compact matrix architectures, which suggested that the BVCs of P. fluorescens enhanced L. monocytogenes biofilm formation through promoting the secretion of extracellular polymers. Moreover, the prominent up-regulated expression of virulence genes further revealed the positive regulation of L. monocytogenes under the influence of BVCs. Additionally, the presence of BVCs significantly elevated the pH and TVB-N levels in both the swimming medium and biofilm broth, thereby exhibiting a strong positive correlation with increased motility and biofilm formation of L. monocytogenes. It highlighted the crucial signaling regulatory role of BVCs in bacterial interactions, while also emphasizing the potential food safety risk associated with the hitchhiking behavior of L. monocytogenes, thereby shedding light on advancements in control strategies for food processing.
Collapse
Affiliation(s)
- Guanghui Zhou
- College of Food Science and Engineering, Shandong Agricultural University, Tai'an Shandong, 271018, China; National R&D Center for Beef Processing Technology, Tai'an, Shandong, 271018, China; International Joint Research Lab (China and Greece) of Digital Transformation as an Enabler for Food Safety and Sustainability, Tai'an, Shandong, 271018, China
| | - Yunge Liu
- College of Food Science and Engineering, Shandong Agricultural University, Tai'an Shandong, 271018, China; National R&D Center for Beef Processing Technology, Tai'an, Shandong, 271018, China; International Joint Research Lab (China and Greece) of Digital Transformation as an Enabler for Food Safety and Sustainability, Tai'an, Shandong, 271018, China
| | - Pengcheng Dong
- College of Food Science and Engineering, Shandong Agricultural University, Tai'an Shandong, 271018, China; National R&D Center for Beef Processing Technology, Tai'an, Shandong, 271018, China; International Joint Research Lab (China and Greece) of Digital Transformation as an Enabler for Food Safety and Sustainability, Tai'an, Shandong, 271018, China
| | - Yanwei Mao
- College of Food Science and Engineering, Shandong Agricultural University, Tai'an Shandong, 271018, China; National R&D Center for Beef Processing Technology, Tai'an, Shandong, 271018, China; International Joint Research Lab (China and Greece) of Digital Transformation as an Enabler for Food Safety and Sustainability, Tai'an, Shandong, 271018, China
| | - Lixian Zhu
- College of Food Science and Engineering, Shandong Agricultural University, Tai'an Shandong, 271018, China; National R&D Center for Beef Processing Technology, Tai'an, Shandong, 271018, China; International Joint Research Lab (China and Greece) of Digital Transformation as an Enabler for Food Safety and Sustainability, Tai'an, Shandong, 271018, China
| | - Xin Luo
- College of Food Science and Engineering, Shandong Agricultural University, Tai'an Shandong, 271018, China; National R&D Center for Beef Processing Technology, Tai'an, Shandong, 271018, China; International Joint Research Lab (China and Greece) of Digital Transformation as an Enabler for Food Safety and Sustainability, Tai'an, Shandong, 271018, China
| | - Yimin Zhang
- College of Food Science and Engineering, Shandong Agricultural University, Tai'an Shandong, 271018, China; National R&D Center for Beef Processing Technology, Tai'an, Shandong, 271018, China; International Joint Research Lab (China and Greece) of Digital Transformation as an Enabler for Food Safety and Sustainability, Tai'an, Shandong, 271018, China.
| |
Collapse
|
2
|
Marra D, Orillo E, Toscano G, Petala M, Karapantsios TD, Caserta S. The role of air relative humidity on the wettability of Pseudomonas fluorescens AR11 biofilms. Colloids Surf B Biointerfaces 2024; 237:113831. [PMID: 38508084 DOI: 10.1016/j.colsurfb.2024.113831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 02/22/2024] [Accepted: 02/29/2024] [Indexed: 03/22/2024]
Abstract
Biofilms are complex porous materials formed by microorganisms, polysaccharides, proteins, eDNA, inorganic matter, and water. They are ubiquitous in various environmental niches and are known to grow at solid-liquid, solid-air and air-liquid interfaces, often causing problems in several industrial and sanitary fields. Their removal is a challenge in many applications and numerous studies have been conducted to identify promising chemical species as cleaning agents. While these substances target specific components of biofilm structure, the role of water content in biofilm, and how it can influence wettability and detergent absorption have been quite neglected in the literature. Estimating water content in biofilm is a challenging task due to its heterogeneity in morphology and chemical composition. In this study, we controlled water content in Pseudomonas fluorescens AR 11 biofilms grown on submerged glass slides by regulating environmental relative humidity after drying. Interfacial properties of biofilm were investigated by measuring wetting of water and soybean oil. The morphology of biofilm structure was evaluated using Confocal Laser Scanning Microscopy and Scanning Electron Microscopy. The results showed that biofilm water content has a significant and measurable effect on its wettability, leading to the hypothesis that a preliminary control of water content can play a crucial role in biofilm removal process.
Collapse
Affiliation(s)
- Daniele Marra
- DICMaPI, Università di Napoli Federico II, P.le V.Tecchio 80, Napoli 80125, Italy
| | - Emilia Orillo
- DICMaPI, Università di Napoli Federico II, P.le V.Tecchio 80, Napoli 80125, Italy
| | - Giuseppe Toscano
- DICMaPI, Università di Napoli Federico II, P.le V.Tecchio 80, Napoli 80125, Italy
| | - Maria Petala
- Department of Civil Engineering, University Box 487, Thessaloniki 54 124, Greece
| | - Thodoris D Karapantsios
- Department of Chemical Technology and Industrial Chemistry, School of Chemistry, Aristotle University, University Box 116, 541 24 Thessaloniki, Greece
| | - Sergio Caserta
- DICMaPI, Università di Napoli Federico II, P.le V.Tecchio 80, Napoli 80125, Italy; CEINGE, Advanced Biotechnologies, Naples 80145, Italy.
| |
Collapse
|
3
|
Yu H, Lin J, Wang M, Ying S, Yuan S, Guo Y, Xie Y, Yao W. Molecular and proteomic response of Pseudomonas fluorescens biofilm cultured on lettuce (Lactuca sativa L.) after ultrasound treatment at different intensity levels. Food Microbiol 2024; 117:104387. [PMID: 37919011 DOI: 10.1016/j.fm.2023.104387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 09/17/2023] [Indexed: 11/04/2023]
Abstract
Ultrasonic treatment is widely used for surface cleaning of vegetables in the processing of agricultural products. In the present study, the molecular and proteomic response of Pseudomonas fluorescens biofilm cultured on lettuce was investigated after ultrasound treatment at different intensity levels. The results show that the biofilm was efficiently removed after ultrasound treatment with intensity higher than 21.06 W/cm2. However, at an intensity of less than 18.42 W/cm2, P. fluorescens was stimulated by ultrasound leading to promoted bacterial growth, extracellular protease activity, extracellular polysaccharide secretion (EPS), and synthesis of acyl-homoserine lactones (AHLs) as quorum-sensing signaling molecules. The expression of biofilm-related genes, stress response, and dual quorum sensing system was upregulated during post-treatment ultrasound. Proteomic analysis showed that ultrasound activated proteins in the flagellar system, which led to changes in bacterial tendency; meanwhile, a large number of proteins in the dual-component system began to be regulated. ABC transporters accelerated the membrane transport of substances inside and outside the cell membrane and equalized the permeability conditions of the cell membrane. In addition, the expression of proteins related to DNA repair was upregulated, suggesting that bacteria repair damaged DNA after ultrasound exposure.
Collapse
Affiliation(s)
- Hang Yu
- State Key Laboratory of Food Science and Resource, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; School of Food Science and Technology, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China.
| | - Jiang Lin
- State Key Laboratory of Food Science and Resource, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; School of Food Science and Technology, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China
| | - Mengru Wang
- State Key Laboratory of Food Science and Resource, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; School of Food Science and Technology, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China
| | - Su Ying
- State Key Laboratory of Food Science and Resource, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; School of Food Science and Technology, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China
| | - Shaofeng Yuan
- State Key Laboratory of Food Science and Resource, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; School of Food Science and Technology, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China
| | - Yahui Guo
- State Key Laboratory of Food Science and Resource, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; School of Food Science and Technology, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China
| | - Yunfei Xie
- State Key Laboratory of Food Science and Resource, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; School of Food Science and Technology, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China
| | - Weirong Yao
- State Key Laboratory of Food Science and Resource, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; School of Food Science and Technology, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, No.1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, China.
| |
Collapse
|
4
|
Jia Y, Niu H, Zhao P, Li X, Yan F, Wang C, Qiu Z. Synergistic biocontrol of Bacillus subtilis and Pseudomonas fluorescens against early blight disease in tomato. Appl Microbiol Biotechnol 2023; 107:6071-6083. [PMID: 37540249 DOI: 10.1007/s00253-023-12642-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 05/04/2023] [Accepted: 06/15/2023] [Indexed: 08/05/2023]
Abstract
Early blight of tomato caused by Alternaria solani results in significant crop losses. In this study, Bacillus subtilis J3 and Pseudomonas fluorescens J8 were co-cultured as a synthetic microbial community (BCA) for synergistic biocontrol of A. solani, and the inhibition mechanism was investigated. BCA presented an inhibition ration against A. solani at 94.91%, which lowered the disease incidence by 38.26-42.87%; reduced peroxidase, catalase, superoxide dismutase activity of tomatoes by 73.11-90.22%; and promoted the biomass by 66.91-489.21%. With BCA protection, the relative expression of tomato resistance genes (including gPAL2, SWRKY, PR-10, and CHI) in roots and leaves was 12.83-90.70% lower than without protection. BCA also significantly altered the rhizosphere and phyllosphere microbial community. The abundance of potentially beneficial bacteria, including Bacillus, Pseudomonas, Arthrobacter, Lysobacter, and Rhizobium, elevated by 6.58-192.77%. They were negatively correlated with resistance gene expression, indicating their vital involvement in disease control. These results provided essential information on the synergistic biocontrol mechanism of bacteria against pathogens, which could contribute to developing novel biocontrol strategies. KEY POINTS: • Bacillus and Pseudomonas present a synergistic biocontrol effect against A. solani. • Biocontrol prevents pathogen damage and improves tomato growth and systemic resistance. • Beneficial bacteria thrive in the rhizosphere is the key to microbial regulation.
Collapse
Affiliation(s)
- Yinxue Jia
- School of Life Science and Engineering, Southwest Jiaotong University, No. 111 Second Ring Road, Chengdu, 610031, Sichuan, People's Republic of China
| | - Huan Niu
- School of Life Science and Engineering, Southwest Jiaotong University, No. 111 Second Ring Road, Chengdu, 610031, Sichuan, People's Republic of China
| | - Peng Zhao
- School of Life Science and Engineering, Southwest Jiaotong University, No. 111 Second Ring Road, Chengdu, 610031, Sichuan, People's Republic of China
| | - Xing Li
- School of Life Science and Engineering, Southwest Jiaotong University, No. 111 Second Ring Road, Chengdu, 610031, Sichuan, People's Republic of China
| | - Fangfang Yan
- Panzhihua City Company, Sichuan Tobacco Company, China National Tobacco Corporation, Panzhihua, 617000, Sichuan, People's Republic of China
| | - Can Wang
- School of Life Science and Engineering, Southwest Jiaotong University, No. 111 Second Ring Road, Chengdu, 610031, Sichuan, People's Republic of China.
| | - Zhongping Qiu
- School of Life Science and Engineering, Southwest Jiaotong University, No. 111 Second Ring Road, Chengdu, 610031, Sichuan, People's Republic of China.
| |
Collapse
|
5
|
Pastora AB, O’Toole GA. The regulator FleQ both transcriptionally and post-transcriptionally regulates the level of RTX adhesins of Pseudomonas fluorescens. J Bacteriol 2023; 205:e0015223. [PMID: 37655913 PMCID: PMC10521353 DOI: 10.1128/jb.00152-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 07/07/2023] [Indexed: 09/02/2023] Open
Abstract
Biofilm formation by the Gram-negative, Gammaproteobacteria Pseudomonas fluorescens relies on the repeats-in-toxin adhesins LapA and MapA in the cytoplasm, secretion of these adhesins through their respective type 1 secretion systems, and retention at the cell surface. Published work has shown that retention of the adhesins occurs via a post-translational mechanism involving the cyclic-di-GMP receptor LapD and the protease LapG. However, little is known about the underlying mechanisms that regulate the level of these adhesins. Here, we demonstrate that the master regulator FleQ modulates biofilm formation by both transcriptionally and post-transcriptionally regulating LapA and MapA. We find that a ΔfleQ mutant has a biofilm formation defect compared to the wild-type (WT) strain, which is attributed in part to a decrease in LapA and MapA abundance in the cell, despite the ΔfleQ mutant having increased levels of lapA and mapA transcripts compared to the WT strain. Through transposon mutagenesis and subsequent genetic analysis, we found that overstimulation of the Gac/Rsm pathway partially rescues biofilm formation in the ΔfleQ mutant background. Collectively, these findings provide evidence that FleQ regulates biofilm formation by both transcriptionally regulating the expression of the lapA and mapA genes and post-transcriptionally regulating the abundance of LapA and MapA, and that activation of the Gac/Rsm pathway can post-transcriptionally enhance biofilm formation by P. fluorescens. IMPORTANCE Biofilm formation is a highly coordinated process that bacteria undergo to colonize a variety of surfaces. For Pseudomonas fluorescens, biofilm formation requires the production and localization of repeats-in-toxin adhesins to the cell surface. To date, little is known about the underlying mechanisms that regulate biofilm formation by P. fluorescens. Here, we identify FleQ as a key regulator of biofilm formation that modulates both gene expression and abundance of LapA and MapA through both a transcriptional and post-transcriptional mechanism. We provide further evidence implicating activation of the Gac/Rsm system in FleQ-dependent regulation of biofilm formation. Together, our findings uncover evidence for a dual mechanism of transcriptional and post-transcriptional regulation of the LapA and MapA adhesins.
Collapse
Affiliation(s)
- Alexander B. Pastora
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - George A. O’Toole
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| |
Collapse
|
6
|
Del Arco A, Becks L, de Vicente I. Population dynamics hide phenotypic changes driven by subtle chemical exposures: implications for risk assessments. Ecotoxicology 2023; 32:281-289. [PMID: 36871096 PMCID: PMC10102127 DOI: 10.1007/s10646-023-02637-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 02/15/2023] [Indexed: 06/18/2023]
Abstract
Ecological risk assessment of chemicals focuses on the response of different taxa in isolation not taking ecological and evolutionary interplay in communities into account. Its consideration would, however, allow for an improved assessment by testing for implications within and across trophic levels and changes in the phenotypic and genotypic diversity within populations. We present a simple experimental system that can be used to evaluate the ecological and evolutionary responses to chemical exposure at microbial community levels. We exposed a microbial model system of the ciliate Tetrahymena thermophila (predator) and the bacterium Pseudomonas fluorescens (prey) to iron released from Magnetic Particles (MP-Fedis), which are Phosphorus (P) adsorbents used in lake restoration. Our results show that while the responses of predator single population size differed across concentrations of MP-Fedis and the responses of prey from communities differed also across concentration of MP-Fedis, the community responses (species ratio) were similar for the different MP-Fedis concentrations. Looking further at an evolutionary change in the bacterial preys' defence, we found that MP-Fedis drove different patterns and dynamics of defence evolution. Overall, our study shows how similar community dynamics mask changes at evolutionary levels that would be overlooked in the design of current risk assessment protocols where evolutionary approaches are not considered.
Collapse
Affiliation(s)
- Ana Del Arco
- Community Dynamics Group, Department of Evolutionary Ecology, Max Planck Institute for Evolutionary Biology, 24306, Plön, Germany.
- Limnological Institute, Biology Department, University of Konstanz, 78464, Konstanz/Egg, Germany.
| | - Lutz Becks
- Community Dynamics Group, Department of Evolutionary Ecology, Max Planck Institute for Evolutionary Biology, 24306, Plön, Germany
- Limnological Institute, Biology Department, University of Konstanz, 78464, Konstanz/Egg, Germany
| | - Inmaculada de Vicente
- Departamento de Ecología, Facultad de Ciencias, Universidad de Granada, Granada, 18071, Spain
| |
Collapse
|
7
|
Su Y, Jiang L, Chen D, Yu H, Yang F, Guo Y, Xie Y, Yao W. In vitro and in silico approaches to investigate antimicrobial and biofilm removal efficacies of combined ultrasonic and mild thermal treatment against Pseudomonas fluorescens. Ultrason Sonochem 2022; 83:105930. [PMID: 35114554 PMCID: PMC8818575 DOI: 10.1016/j.ultsonch.2022.105930] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/10/2022] [Accepted: 01/18/2022] [Indexed: 05/16/2023]
Abstract
A combined ultrasonic and thermal (US-TM) treatment was developed in this study to achieve a high efficacy of P. fluorescens biofilm control. The present study demonstrated that combined a moderate ultrasound treatment (power ≥ 80 W) and a mild heat (up to 50 °C) largely destroyed biofilm structure in 15 min and removed>65.63% of biofilm from a glass slide where cultivated the P. fluorescens biofilm. Meanwhile, the viable cell count was decreased from 10.72 to 6.48 log10CUF/mL. Differences in biofilm removal and lethal modes of US-TM treatment were confirmed through microscopies analysis in vitro. The ultrasound first contributed to releasing the bacteria in the biofilm to the environment and simultaneously exposing inner bacteria at the deep layer of biofilm depending on shear force, shock waves, acoustic streaming, etc. When the biofilm structure was destroyed, US-TM treatment would synergistically inactivate P. fluorescens cells. In silico studies adopted COMSOL to simulate acoustic pressure and temperature distribution in the bioreactor; both of them were significantly influenced by various factors, such as input power, sonotrode position, materials and volume of container, etc. Facing the biofilm issue existing on the surface of container, boundary conditions were exported and thereby pointing out potential "dead ends" where the ultrasound may not be effectively transduced. Both in vitro and in silico results may inspire the food industry to adopt US-TM treatment to achieve biofilm control.
Collapse
Affiliation(s)
- Ying Su
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China
| | - Lin Jiang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China
| | - Danying Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China
| | - Hang Yu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China.
| | - Fangwei Yang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China
| | - Yahui Guo
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China
| | - Yunfei Xie
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China
| | - Weirong Yao
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, China
| |
Collapse
|
8
|
Baliarda A, Winkler M, Tournier L, Tinsley CR, Aymerich S. Dynamic interspecies interactions and robustness in a four-species model biofilm. Microbiologyopen 2021; 10:e1254. [PMID: 34964290 PMCID: PMC8650569 DOI: 10.1002/mbo3.1254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 11/16/2021] [Accepted: 11/17/2021] [Indexed: 11/18/2022] Open
Abstract
Interspecific interactions within biofilms determine relative species abundance, growth dynamics, community resilience, and success or failure of invasion by an extraneous organism. However, deciphering interspecific interactions and assessing their contribution to biofilm properties and function remain a challenge. Here, we describe the constitution of a model biofilm composed of four bacterial species belonging to four different genera (Rhodocyclus sp., Pseudomonas fluorescens, Kocuria varians, and Bacillus cereus), derived from a biofilm isolated from an industrial milk pasteurization unit. We demonstrate that the growth dynamics and equilibrium composition of this biofilm are highly reproducible. Based on its equilibrium composition, we show that the establishment of this four-species biofilm is highly robust against initial, transient perturbations but less so towards continuous perturbations. By comparing biofilms formed from different numbers and combinations of the constituent species and by fitting a growth model to the experimental data, we reveal a network of dynamic, positive, and negative interactions that determine the final composition of the biofilm. Furthermore, we reveal that the molecular determinant of one negative interaction is the thiocillin I synthesized by the B. cereus strain, and demonstrate its importance for species distribution and its impact on robustness by mutational analysis of the biofilm ecosystem.
Collapse
Affiliation(s)
- Aurélie Baliarda
- INRAE, AgroParisTech, Micalis InstituteUniversité Paris‐SaclayJouy‐en‐JosasFrance
| | - Michèle Winkler
- INRAE, AgroParisTech, Micalis InstituteUniversité Paris‐SaclayJouy‐en‐JosasFrance
| | | | - Colin R. Tinsley
- INRAE, AgroParisTech, Micalis InstituteUniversité Paris‐SaclayJouy‐en‐JosasFrance
| | - Stéphane Aymerich
- INRAE, AgroParisTech, Micalis InstituteUniversité Paris‐SaclayJouy‐en‐JosasFrance
| |
Collapse
|
9
|
Horton JS, Flanagan LM, Jackson RW, Priest NK, Taylor TB. A mutational hotspot that determines highly repeatable evolution can be built and broken by silent genetic changes. Nat Commun 2021; 12:6092. [PMID: 34667151 PMCID: PMC8526746 DOI: 10.1038/s41467-021-26286-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 09/28/2021] [Indexed: 11/08/2022] Open
Abstract
Mutational hotspots can determine evolutionary outcomes and make evolution repeatable. Hotspots are products of multiple evolutionary forces including mutation rate heterogeneity, but this variable is often hard to identify. In this work, we reveal that a near-deterministic genetic hotspot can be built and broken by a handful of silent mutations. We observe this when studying homologous immotile variants of the bacteria Pseudomonas fluorescens, AR2 and Pf0-2x. AR2 resurrects motility through highly repeatable de novo mutation of the same nucleotide in >95% lines in minimal media (ntrB A289C). Pf0-2x, however, evolves via a number of mutations meaning the two strains diverge significantly during adaptation. We determine that this evolutionary disparity is owed to just 6 synonymous variations within the ntrB locus, which we demonstrate by swapping the sites and observing that we are able to both break (>95% to 0%) and build (0% to 80%) a deterministic mutational hotspot. Our work reveals a key role for silent genetic variation in determining adaptive outcomes.
Collapse
Affiliation(s)
- James S Horton
- Milner Centre for Evolution, Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
| | - Louise M Flanagan
- Milner Centre for Evolution, Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Robert W Jackson
- School of Biosciences and Birmingham Institute of Forest Research (BIFoR), University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Nicholas K Priest
- Milner Centre for Evolution, Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Tiffany B Taylor
- Milner Centre for Evolution, Department of Biology & Biochemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
| |
Collapse
|
10
|
Song Y, Wilson AJ, Zhang XC, Thoms D, Sohrabi R, Song S, Geissmann Q, Liu Y, Walgren L, He SY, Haney CH. FERONIA restricts Pseudomonas in the rhizosphere microbiome via regulation of reactive oxygen species. Nat Plants 2021; 7:644-654. [PMID: 33972713 DOI: 10.1038/s41477-021-00914-0] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 04/01/2021] [Indexed: 05/27/2023]
Abstract
Maintaining microbiome structure is critical for the health of both plants and animals. By re-screening a collection of Arabidopsis mutants affecting root immunity and hormone crosstalk, we identified a FERONIA (FER) receptor kinase mutant (fer-8) with a rhizosphere microbiome enriched in Pseudomonas fluorescens without phylum-level dysbiosis. Using microbiome transplant experiments, we found that the fer-8 microbiome was beneficial. The effect of FER on rhizosphere pseudomonads was largely independent of its immune scaffold function, role in development and jasmonic acid autoimmunity. We found that the fer-8 mutant has reduced basal levels of reactive oxygen species (ROS) in roots and that mutants deficient in NADPH oxidase showed elevated rhizosphere pseudomonads. The addition of RALF23 peptides, a FER ligand, was sufficient to enrich P. fluorescens. This work shows that FER-mediated ROS production regulates levels of beneficial pseudomonads in the rhizosphere microbiome.
Collapse
Affiliation(s)
- Yi Song
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, British Columbia, Canada
- Michael Smith Laboratories, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Andrew J Wilson
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Xue-Cheng Zhang
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- DermBiont, Boston, MA, USA
| | - David Thoms
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, British Columbia, Canada
- Michael Smith Laboratories, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Reza Sohrabi
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
| | - Siyu Song
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Quentin Geissmann
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, British Columbia, Canada
- Michael Smith Laboratories, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Yang Liu
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Lauren Walgren
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Sheng Yang He
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
- Department of Biology, Duke University, Durham, NC, USA
- Howard Hughes Medical Institute, Duke University, Durham, NC, USA
| | - Cara H Haney
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, British Columbia, Canada.
- Michael Smith Laboratories, The University of British Columbia, Vancouver, British Columbia, Canada.
| |
Collapse
|
11
|
Nagpal S, Sharma P, Sirari A, Kumawat KC, Wati L, Gupta SC, Mandahal KS. Chickpea (Cicer arietinum L.) as model legume for decoding the co-existence of Pseudomonas fluorescens and Mesorhizobium sp. as bio-fertilizer under diverse agro-climatic zones. Microbiol Res 2021; 247:126720. [PMID: 33592359 DOI: 10.1016/j.micres.2021.126720] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 01/20/2021] [Accepted: 01/30/2021] [Indexed: 11/18/2022]
Abstract
Microbial co-inoculation strategy utilizes a combination of microbes to stimulate plant growth concomitant with an increased phytopathogen tolerance. In the present study, 15 endophytic bacterial isolates from rhizosphere and roots of wild chickpea accessions (Cicer pinnatifidum, C. judiacum, C. bijugum and C. reticulatum) were characterized for morphological, biochemical and physiological traits. Two promising isolates were identified as Pseudomonas fluorescens strain LRE-2 (KR303708.1) and Pseudomonas argentinensis LPGPR-1 (JX239745.1) based on 16S rRNA gene sequencing. Biocompatibility of selected endophytes with Mesorhizobium sp. CH1233, a standard isolate used as a national check in All India Coordinated Research Project (AICRP) was assessed to develop functional combinations capable of producing Indole acetic acid, gibberellins, siderophores and improving seed vigour (in vitro). In vivo synergistic effect of promising combinations was further evaluated under national AICRP, (Chickpea) at two different agro-climatic zones [North-West plain (Ludhiana and Hisar) and Central zones (Sehore)] for three consecutive Rabi seasons (2015-18) to elucidate their effect on symbiotic, soil quality and yield parameters. On the pooled mean basis across locations over the years, combination of Mrh+LRE-2 significantly enhanced symbiotic, soil quality traits and grain yield over Mrh alone and highly positive correlation was obtained between the nodulation traits and grain yield. Superior B: C ratio (1.12) and additional income of Rs 6,505.18 ha-1 was obtained by application of Mrh+LRE-2 over Mrh alone and un-inoculated control. The results demonstrate that dual combination of Mrh and Pseudomonas sp. from wild Cicer relatives can be exploited as a potential bio-fertilizer for increasing soil fertility and improving chickpea productivity under sustainable agriculture.
Collapse
Affiliation(s)
- Sharon Nagpal
- Department of Microbiology, Punjab Agricultural University, Ludhiana, Punjab, 141004, India.
| | - Poonam Sharma
- Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana, Punjab, 141001, India
| | - Asmita Sirari
- Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana, Punjab, 141001, India
| | - K C Kumawat
- Department of Microbiology, Punjab Agricultural University, Ludhiana, Punjab, 141004, India
| | - Leela Wati
- Department of Microbiology, Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana, 125004, India
| | - S C Gupta
- RAK, College of Agriculture, Sehore, Madhya Pradesh, 466001, India
| | - Kamalpreet Singh Mandahal
- Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana, Punjab, 141001, India
| |
Collapse
|
12
|
Martin-Rivilla H, Garcia-Villaraco A, Ramos-Solano B, Gutierrez-Manero FJ, Lucas JA. Metabolic elicitors of Pseudomonas fluorescens N 21.4 elicit flavonoid metabolism in blackberry fruit. J Sci Food Agric 2021; 101:205-214. [PMID: 32623714 DOI: 10.1002/jsfa.10632] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/09/2020] [Accepted: 07/05/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND The beneficial rhizobacterium, Pseudomonas fluorescens N 21.4, and its metabolic elicitors were inoculated in commercial cultivars of blackberry plants (Rubus cv. Loch Ness). Phenolic compounds present in red and black fruit and the expression of structural marker genes of the phenylpropanoid pathway during fruit ripening were studied. RESULTS An inverse relationship between gene expression and accumulation of metabolites was seen, except for the RuDFR gene, which had a direct correlation with cyanidin 3-O-glucoside synthesis, increasing its content 1.3 times when RuDFR was overexpressed in the red fruit of plants inoculated with the metabolic elicitors of P. fluorescens N 21.4, compared with red fruit of plants inoculated with N 21.4. The RuCHS gene also had a fundamental role in the accumulation of metabolites. Both rhizobacterium and metabolic elicitors triggered the flavonoid metabolism, enhancing the catechin and epicatechin content between 1.1 and 1.6 times in the case of red fruit and between 1.1 and 1.8 times in the case of black fruit. Both treatments also boosted the anthocyanin, quercetin, and kaempferol derivative content, highlighting the effects of metabolic elicitors in red fruit and the effects of live rhizobacterium in black fruit. CONCLUSION The metabolic elicitors' capacity to modulate gene expression and to increase secondary metabolites content was demonstrated. This work therefore suggests that they are effective, affordable, easily manageable, and ecofriendly plant inoculants that complement, or are alternatives to, beneficial rhizobacteria. © 2020 Society of Chemical Industry.
Collapse
Affiliation(s)
- Helena Martin-Rivilla
- Plant Physiology, Pharmaceutical and Health Sciences Department, Faculty of Pharmacy, Universidad San Pablo-CEU Universities, Boadilla del Monte, Spain
| | - Ana Garcia-Villaraco
- Plant Physiology, Pharmaceutical and Health Sciences Department, Faculty of Pharmacy, Universidad San Pablo-CEU Universities, Boadilla del Monte, Spain
| | - Beatriz Ramos-Solano
- Plant Physiology, Pharmaceutical and Health Sciences Department, Faculty of Pharmacy, Universidad San Pablo-CEU Universities, Boadilla del Monte, Spain
| | - Francisco J Gutierrez-Manero
- Plant Physiology, Pharmaceutical and Health Sciences Department, Faculty of Pharmacy, Universidad San Pablo-CEU Universities, Boadilla del Monte, Spain
| | | |
Collapse
|
13
|
Rahimi S, Talebi M, Baninasab B, Gholami M, Zarei M, Shariatmadari H. The role of plant growth-promoting rhizobacteria (PGPR) in improving iron acquisition by altering physiological and molecular responses in quince seedlings. Plant Physiol Biochem 2020; 155:406-415. [PMID: 32814277 DOI: 10.1016/j.plaphy.2020.07.045] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/28/2020] [Accepted: 07/28/2020] [Indexed: 05/08/2023]
Abstract
Due to insoluble iron (Fe) sources in soil, limited Fe availability leads to the disruption of the photosynthetic apparatus; this affects the growth and productivity of plants such as quince (Cydonia oblonga) that are very sensitive to low Fe content. Plant growth-promoting rhizobacteria (PGPR) play an important role in the regulation of Fe uptake under its limited availability. Therefore, in this research, two PGPR (Pseudomonas fluorescens and Microccucuce yunnanensis), at two Fe levels [50 μM (Fe-sufficiency) or 5 μM (Fe-deficiency)], were used to investigate the impact of the given bacteria on improving the acquisition of Fe in quince seedlings. Upon Fe-deficiency, the highest shoot and root biomass (7.14 and 6.04 g plant-1 respectively), the greatest chlorophyll concentration (0.89 mg g-1FW), and the largest Fe concentrations in roots and shoots (30% and 48.7%, respectively) were shown in the quince treated with M. yunnanensis. Both PGPR increased the root citric acid and the phenolic compound concentration. Two days after Fe-deficiency and PGPR treatments, a 1.5- fold increase, was observed in the expression of HA7. The highest PAL1 gene expression and the greatest PAL activity (95.76 μmol cinnamic acid g-1FW) were obtained from the M. yunnanensis treatment. The expression of the FRO2 gene was also affected by Fe-deficiency and PGPR treatments, resulting in an increase in the FCR activity and a surge in the Fe concentrations of leaves and roots. It could, therefore, be concluded that the PGPR modulated Fe acquisition in the quince seedlings upon Fe-deficiency by influencing the physico-chemical and molecular responses.
Collapse
Affiliation(s)
- Sareh Rahimi
- Department of Horticulture, College of Agriculture, Isfahan University of Technology, 84156-83111, Isfahan, Iran
| | - Majid Talebi
- Department of Biotechnology, College of Agriculture, Isfahan University of Technology, 8415683111, Isfahan, Iran.
| | - Bahram Baninasab
- Department of Horticulture, College of Agriculture, Isfahan University of Technology, 84156-83111, Isfahan, Iran
| | - Mahdiyeh Gholami
- Department of Horticulture, College of Agriculture, Isfahan University of Technology, 84156-83111, Isfahan, Iran
| | - Mehdi Zarei
- Department of Soil Science, College of Agriculture, Shiraz University, Shiraz, Iran
| | - Hossein Shariatmadari
- Department of Soil Science, College of Agriculture, Isfahan University of Technology, 8415683111, Isfahan, Iran
| |
Collapse
|
14
|
Wu Y, Ma L, Liu Q, Topalović O, Wang Q, Yang X, Feng Y. Pseudomonas fluorescens accelerates a reverse and long-distance transport of cadmium and sucrose in the hyperaccumulator plant Sedum alfredii. Chemosphere 2020; 256:127156. [PMID: 32559889 DOI: 10.1016/j.chemosphere.2020.127156] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/30/2020] [Accepted: 05/19/2020] [Indexed: 06/11/2023]
Abstract
Plant growth-promoting bacteria (PGPB) can promote root uptake and shoot accumulation of cadmium (Cd) in hyperaccumulator plants, but the mechanisms by which PGPB accelerate root-to-shoot transport of Cd is still unknown. A better understanding of these mechanisms is necessary to develop the strategies that can promote the practical phytoextraction of Cd-polluted soils. In this study, we found that Pseudomonas fluorescens accelerates a reversed and a long-distance transport of Cd and sucrose in Sedum alfredii, by examining the xylem and phloem sap and by quantifying the concentrations of Cd and sucrose in shoot and root. The transcriptome sequencing has revealed the up-regulated expressions of starch metabolism and sucrose biosynthesis related genes in the shoots of Cd hyperaccumulator plant S. alfredii that was inoculated with PGPB P. fluorescens. In addition, the genes of sugar, cation and anion transporters were also up-regulated by bacterial treatment, showing a complicated co-expression network with sucrose biosynthesis related genes. The expression levels of Cd transporter genes, such as ZIP1, ZIP2, HMA2, HMA3 and CAX2, were elevated after PGPB inoculation. As a result, the PGPB successfully colonized the root, and promoted the sucrose shoot-to-root transport and Cd root-to-shoot transport in S. alfredii. Since non-photosynthetic root-associated bacteria usually obtain sugars from photosynthetic plants, our results highlight the importance of PGPB-induced changes in hyperaccumlator plants for both the host and the PGPB.
Collapse
Affiliation(s)
- Yingjie Wu
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China; Department of Agroecology, Faculty of Technical Sciences, Aarhus University, Forsøgsvej 1, 4200, Slagelse, Denmark
| | - Luyao Ma
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Qizhen Liu
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Olivera Topalović
- Department of Agroecology, Faculty of Technical Sciences, Aarhus University, Forsøgsvej 1, 4200, Slagelse, Denmark
| | - Qiong Wang
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Xiaoe Yang
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Ying Feng
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
| |
Collapse
|
15
|
Encinas N, Yang CY, Geyer F, Kaltbeitzel A, Baumli P, Reinholz J, Mailänder V, Butt HJ, Vollmer D. Submicrometer-Sized Roughness Suppresses Bacteria Adhesion. ACS Appl Mater Interfaces 2020; 12:21192-21200. [PMID: 32142252 PMCID: PMC7226781 DOI: 10.1021/acsami.9b22621] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Accepted: 02/26/2020] [Indexed: 05/12/2023]
Abstract
Biofilm formation is most commonly combatted with antibiotics or biocides. However, proven toxicity and increasing resistance of bacteria increase the need for alternative strategies to prevent adhesion of bacteria to surfaces. Chemical modification of the surfaces by tethering of functional polymer brushes or films provides a route toward antifouling coatings. Furthermore, nanorough or superhydrophobic surfaces can delay biofilm formation. Here we show that submicrometer-sized roughness can outweigh surface chemistry by testing the adhesion of E. coli to surfaces of different topography and wettability over long exposure times (>7 days). Gram-negative and positive bacterial strains are tested for comparison. We show that an irregular three-dimensional layer of silicone nanofilaments suppresses bacterial adhesion, both in the presence and absence of an air cushion. We hypothesize that a 3D topography can delay biofilm formation (i) if bacteria do not fit into the pores of the coating or (ii) if bending of the bacteria is required to adhere. Thus, such a 3D topography offers an underestimated possibility to design antibacterial surfaces that do not require biocides or antibiotics.
Collapse
Affiliation(s)
- Noemí Encinas
- Max Planck Institute
for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Ching-Yu Yang
- Max Planck Institute
for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Florian Geyer
- Max Planck Institute
for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Anke Kaltbeitzel
- Max Planck Institute
for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Philipp Baumli
- Max Planck Institute
for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Jonas Reinholz
- Max Planck Institute
for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Department of Dermatology, University Medical Center of the Johannes Gutenberg-University
Mainz, Langenbeckstrasse
1, Mainz 55131, Germany
| | - Volker Mailänder
- Max Planck Institute
for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Department of Dermatology, University Medical Center of the Johannes Gutenberg-University
Mainz, Langenbeckstrasse
1, Mainz 55131, Germany
| | - Hans-Jürgen Butt
- Max Planck Institute
for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Doris Vollmer
- Max Planck Institute
for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| |
Collapse
|
16
|
Jana S, Charlton SGV, Eland LE, Burgess JG, Wipat A, Curtis TP, Chen J. Nonlinear rheological characteristics of single species bacterial biofilms. NPJ Biofilms Microbiomes 2020; 6:19. [PMID: 32286319 PMCID: PMC7156450 DOI: 10.1038/s41522-020-0126-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Accepted: 03/09/2020] [Indexed: 12/15/2022] Open
Abstract
Bacterial biofilms in natural and artificial environments perform a wide array of beneficial or detrimental functions and exhibit resistance to physical as well as chemical perturbations. In dynamic environments, where periodic or aperiodic flows over surfaces are involved, biofilms can be subjected to large shear forces. The ability to withstand these forces, which is often attributed to the resilience of the extracellular matrix. This attribute of the extracellular matrix is referred to as viscoelasticity and is a result of self-assembly and cross-linking of multiple polymeric components that are secreted by the microbes. We aim to understand the viscoelastic characteristic of biofilms subjected to large shear forces by performing Large Amplitude Oscillatory Shear (LAOS) experiments on four species of bacterial biofilms: Bacillus subtilis, Comamonas denitrificans, Pseudomonas fluorescens and Pseudomonas aeruginosa. We find that nonlinear viscoelastic measures such as intracycle strain stiffening and intracycle shear thickening for each of the tested species, exhibit subtle or distinct differences in the plot of strain amplitude versus frequency (Pipkin diagram). The biofilms also exhibit variability in the onset of nonlinear behaviour and energy dissipation characteristics, which could be a result of heterogeneity of the extracellular matrix constituents of the different biofilms. The results provide insight into the nonlinear rheological behaviour of biofilms as they are subjected to large strains or strain rates; a situation that is commonly encountered in nature, but rarely investigated.
Collapse
Affiliation(s)
- Saikat Jana
- School of Biomedical Sciences, University of Leeds, Leeds, UK.
- School of Engineering, Newcastle University, Newcastle Upon Tyne, UK.
| | | | - Lucy E Eland
- Interdisciplinary Computing & Complex BioSystems Research Group, School of Computing, Newcastle University, Newcastle upon Tyne, UK
| | - J Grant Burgess
- School of Natural & Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Anil Wipat
- Interdisciplinary Computing & Complex BioSystems Research Group, School of Computing, Newcastle University, Newcastle upon Tyne, UK
| | - Thomas P Curtis
- School of Engineering, Newcastle University, Newcastle Upon Tyne, UK
| | - Jinju Chen
- School of Engineering, Newcastle University, Newcastle Upon Tyne, UK.
| |
Collapse
|
17
|
Su L, Xu C, Cai L, Qiu N, Hou M, Wang J. Susceptibility and immune responses after challenge with Flavobacterium columnare and Pseudomonas fluorescens in conventional and specific pathogen-free rare minnow (Gobiocypris rarus). Fish Shellfish Immunol 2020; 98:875-886. [PMID: 31751657 DOI: 10.1016/j.fsi.2019.11.047] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 11/16/2019] [Accepted: 11/18/2019] [Indexed: 06/10/2023]
Abstract
The susceptibility of fish from different culture environments to bacterial infection is not well known. The susceptibility and pathological changes of conventional (CV) and specific pathogen-free (SPF) rare minnow (Gobiocypris rarus) infected with two gram-negative bacteria, Flavobacterium columnare and Pseudomonas fluorescens are investigated. Rare minnows were intraperitoneally challenged with two bacterial species to first determine semi-lethal doses (LD50), and then with the LD50 dose, determine innate immune response. Infected rare minnows developed characteristic red bellies and then died. LD50 doses of F. columnare and P. fluorescens were 4.586 × 108 cfu/mL and 2.319 × 1010 cfu/mL for CV rare minnow, and 2.575 × 108 cfu/mL and 1.935 × 1010 cfu/mL, respectively, for SPF rare minnow. The results of RT-PCR showed that the highest levels of toll-like receptor 3 (TLR3), interleukin-6 (IL-6), interferon-2 (IFN-2) and rare minnow Z-DNA binding protein kinase (GrPKZ) mRNA were noticed at 6-48 h post-infection (hpi). In addition, TLR3, IL-6 and IFN-2 in F. columnare challenged rare minnow were more highly expressed than those in P. fluorescens challenged rare minnow, whereas as opposed in the expression of GrPKZ mRNA. Stimulation of innate immune responses is closely related to bacterial virulence. SPF rare minnow might be more susceptible to these bacteria than CV rare minnow, possibly due to their clean environment and lack of resistance. We speculate that clean environment renders rare minnow more susceptible to bacterial infections.
Collapse
Affiliation(s)
- Liangxia Su
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China; University of Chinese Academy of Sciences, Beijing, China
| | - Chunsen Xu
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China; University of Chinese Academy of Sciences, Beijing, China
| | - Lei Cai
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China; University of Chinese Academy of Sciences, Beijing, China; Guangdong Laboratory Animals Monitoring Institute, Guangzhou, Guangdong, China
| | - Ning Qiu
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China; University of Chinese Academy of Sciences, Beijing, China
| | - Miaomiao Hou
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China
| | - Jianwei Wang
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China.
| |
Collapse
|
18
|
Wang Z, Mei X, Du M, Chen K, Jiang M, Wang K, Zalán Z, Kan J. Potential modes of action of Pseudomonas fluorescens ZX during biocontrol of blue mold decay on postharvest citrus. J Sci Food Agric 2020; 100:744-754. [PMID: 31637724 DOI: 10.1002/jsfa.10079] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 10/01/2019] [Accepted: 10/06/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND The application of chemical fungicides is currently the main method for the control of postharvest decay of fruits and vegetables. However, public concern has been growing towards the effect of fungicides on food safety, human health and environmental pollution. Thus, interest in microbial biocontrol agent development has grown, such agents being considered both safe and environmentally friendly. Pseudomonas fluorescens is widely distributed in nature, and one of the most valuable biocontrol and plant growth-promoting rhizobacteria. In this study, the efficacy and the potential associated modes of action of P. fluorescens ZX against Penicillium italicum on oranges (Citrus sinensis Osbeck) were investigated. RESULTS The application of P. fluorescens ZX significantly reduced blue mold lesion size and incidence in comparison to the control, where P. fluorescens ZX was effective when applied preventatively but not curatively. In dual cultures, treatment with cell-free autoclaved cultures or culture filtrate had a limited capacity to suppress P. italicum, while P. italicum was inhibited by bacterial fluid and bacterial suspension with living cells in vitro. The P. fluorescens ZX isolate displayed protease, but not chitinase, glucanase or cellulose, activity, and produced siderophores and volatile organic compounds with antifungal abilities. Competition tests showed P. fluorescens ZX could use fructose, sucrose, aspartic acid, threonine, serine, glycine, valine, lysine and proline better than P. italicum. Furthermore, an effective biofilm that peaked after a 24-hour incubation at 30 °C was formed by the P. fluorescens ZX isolate. Light microscopy and scanning electron microscopy observations indicate the P. fluorescens ZX isolate could not undergo direct parasitism or hyperparasitism. CONCLUSIONS Competition for nutrients and niches, biofilm formation, inhibition of spore germination and mycelial growth, and production of inhibitory metabolites may play important roles in P. fluorescens ZX antagonism of P. italicum. © 2019 Society of Chemical Industry.
Collapse
Affiliation(s)
- Zhirong Wang
- College of Food Science, Southwest University, Chongqing, PR China
- Chinese-Hungarian Cooperative Research Centre for Food Science, Chongqing, PR China
| | - Xiaofei Mei
- College of Food Science, Southwest University, Chongqing, PR China
- Laboratory of Quality & Safety Risk Assessment for Agro-products on Storage and Preservation (Chongqing), Ministry of Agriculture, Chongqing, PR China
| | - Muying Du
- College of Food Science, Southwest University, Chongqing, PR China
- Chinese-Hungarian Cooperative Research Centre for Food Science, Chongqing, PR China
- Laboratory of Quality & Safety Risk Assessment for Agro-products on Storage and Preservation (Chongqing), Ministry of Agriculture, Chongqing, PR China
| | - Kewei Chen
- College of Food Science, Southwest University, Chongqing, PR China
- Laboratory of Quality & Safety Risk Assessment for Agro-products on Storage and Preservation (Chongqing), Ministry of Agriculture, Chongqing, PR China
| | - Mengyao Jiang
- College of Food Science, Southwest University, Chongqing, PR China
- Chinese-Hungarian Cooperative Research Centre for Food Science, Chongqing, PR China
| | - Kaituo Wang
- Chinese-Hungarian Cooperative Research Centre for Food Science, Chongqing, PR China
- College of Life Science and Engineering, Chongqing Three Gorges University, Chongqing, PR China
| | - Zsolt Zalán
- Chinese-Hungarian Cooperative Research Centre for Food Science, Chongqing, PR China
- Food Science Research Institute of National Agricultural Research and Innovation Center, Budapest, Hungary
| | - Jianquan Kan
- College of Food Science, Southwest University, Chongqing, PR China
- Chinese-Hungarian Cooperative Research Centre for Food Science, Chongqing, PR China
- Laboratory of Quality & Safety Risk Assessment for Agro-products on Storage and Preservation (Chongqing), Ministry of Agriculture, Chongqing, PR China
| |
Collapse
|
19
|
Pousti M, Lefèvre T, Amirdehi MA, Greener J. A surface spectroscopy study of a Pseudomonas fluorescens biofilm in the presence of an immobilized air bubble. Spectrochim Acta A Mol Biomol Spectrosc 2019; 222:117163. [PMID: 31177008 DOI: 10.1016/j.saa.2019.117163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 05/15/2019] [Accepted: 05/26/2019] [Indexed: 06/09/2023]
Abstract
A linear spectral mapping technique was applied to monitor the growth of biomolecular absorption bands at the bio-interface of a nascent Pseudomonas fluorescens biofilm during and after interaction with a surface-adhered air bubble. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectra were obtained in different locations in a microchannel with adequate spatial and temporal resolution to study the effect of a static bubble on the evolution of protein and lipid signals at the ATR crystal surface. The results reveal that the presence of a bubble during the lag phase modified levels of extracellular lipids and affected a surface restructuring process, many hours after the bubble's disappearance.
Collapse
Affiliation(s)
- M Pousti
- Département de Chimie, Faculté des sciences et de génie, Université Laval, Québec City, QC, Canada; Centre de recherche sur les matériaux avancés (CERMA), Canada; Centre québécois sur les matériaux fonctionnels (CQMF), Canada
| | - T Lefèvre
- Département de Chimie, Faculté des sciences et de génie, Université Laval, Québec City, QC, Canada; Centre de recherche sur les matériaux avancés (CERMA), Canada; Centre québécois sur les matériaux fonctionnels (CQMF), Canada
| | - M Abbaszadeh Amirdehi
- Département de Chimie, Faculté des sciences et de génie, Université Laval, Québec City, QC, Canada
| | - J Greener
- Département de Chimie, Faculté des sciences et de génie, Université Laval, Québec City, QC, Canada; CHU de Québec, centre de recherche, Université Laval, 10 rue de l'Espinay, Québec, QC, Canada; Centre de recherche sur les matériaux avancés (CERMA), Canada; Centre québécois sur les matériaux fonctionnels (CQMF), Canada.
| |
Collapse
|
20
|
Fulaz S, Hiebner D, Barros CHN, Devlin H, Vitale S, Quinn L, Casey E. Ratiometric Imaging of the in Situ pH Distribution of Biofilms by Use of Fluorescent Mesoporous Silica Nanosensors. ACS Appl Mater Interfaces 2019; 11:32679-32688. [PMID: 31418546 DOI: 10.1021/acsami.9b09978] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Biofilms are communities of microorganisms enclosed in a self-generated matrix of extracellular polymeric substances. While biofilm recalcitrance and persistence are caused by several factors, a reduction in antimicrobial susceptibility has been closely associated with the generation of pH gradients within the biofilm structure. Cells embedded within the biofilm create a localized acidic microenvironment, which is unaffected by the external pH. Therefore, pH monitoring is a promising approach for understanding the complexities of a three-dimensional heterogeneous biofilm. A fluorescent pH nanosensor was designed through the synthesis of mesoporous silica nanoparticles (47 ± 5 nm diameter) conjugated to a pH-sensitive dye (fluorescein) and a pH-insensitive dye (rhodamine B) as an internal standard (dye-MSNs). The fluorescence intensity of fluorescein (IF) reduced significantly as the pH was decreased from 8.5 to 3.5. In contrast, the fluorescence intensity of rhodamine B (IR) remained constant at any pH. The ratio of IF/IR produced a sigmoidal curve with respect to the pH, in a working pH range between 4.5 and 7.5. Dye-MSNs enabled the measurement of pH gradients within Pseudomonas fluorescens WCS 365 biofilm microcolonies. The biofilms showed spatially distinct low-pH regions that were enclosed into large clusters corresponding to high-cell-density areas. Also present were small low-pH areas that spread indistinctly throughout the microcolony caused by the mass transfer effect. The lowest detected pH within the inner core of the microcolonies was 5.1, gradually increasing to a neutral pH toward the exterior of the microcolonies. The dye-MSNs were able to fully penetrate the biofilm matrix and allowed a quantitative ratiometric analysis of pH gradients and distribution throughout the biofilm, which was independent of the nanoparticle concentration.
Collapse
Affiliation(s)
- Stephanie Fulaz
- UCD School of Chemical and Bioprocess Engineering , University College Dublin , Belfield, Dublin 4 Dublin , Ireland
| | - Dishon Hiebner
- UCD School of Chemical and Bioprocess Engineering , University College Dublin , Belfield, Dublin 4 Dublin , Ireland
| | - Caio H N Barros
- UCD School of Chemical and Bioprocess Engineering , University College Dublin , Belfield, Dublin 4 Dublin , Ireland
| | - Henry Devlin
- UCD School of Chemical and Bioprocess Engineering , University College Dublin , Belfield, Dublin 4 Dublin , Ireland
| | - Stefania Vitale
- UCD School of Chemical and Bioprocess Engineering , University College Dublin , Belfield, Dublin 4 Dublin , Ireland
| | - Laura Quinn
- UCD School of Chemical and Bioprocess Engineering , University College Dublin , Belfield, Dublin 4 Dublin , Ireland
| | - Eoin Casey
- UCD School of Chemical and Bioprocess Engineering , University College Dublin , Belfield, Dublin 4 Dublin , Ireland
| |
Collapse
|
21
|
Schulz P, Pajdak-Czaus J, Robak S, Dastych J, Siwicki AK. Bacteriophage-based cocktail modulates selected immunological parameters and post-challenge survival of rainbow trout (Oncorhynchus mykiss). J Fish Dis 2019; 42:1151-1160. [PMID: 31132804 DOI: 10.1111/jfd.13026] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 04/25/2019] [Indexed: 06/09/2023]
Abstract
Recently, a rapid increase in the resistance of pathogenic bacteria to antibiotics and chemotherapeutics admitted for use in aquaculture has been observed. This happens especially often in intensive breeding. The use of drugs in closed circuits is problematic because it can damage biological filters. Therefore, in recent years, there has been a growing interest in natural methods of combating pathogens. These include bacteriophages. The aim of the study was to determine the safety of the new BAFADOR® bacteriophage-based preparation, its effect on selected immunological parameters and the effectiveness of prophylactic and therapeutic use after experimental infections with pathogenic bacteria Aeromonas hydrophila and Pseudomonas fluorescens. The use of BAFADOR® increased the activity of lysozyme, total protein level and immunoglobulin level. The level of ceruloplasmin in the rainbow trout serum remained unchanged regardless of the route of administration of the preparation. Potential killing activity and metabolic activity of spleen phagocytes and proliferation of pronephros lymphocytes were higher compared to the control group. Both therapeutic and prophylactic application of the preparation after mixed experimental infection of A. hydrophila and P. fluorescens limited the mortality of rainbow trout.
Collapse
Affiliation(s)
- Patrycja Schulz
- Department of Microbiology and Clinical Immunology, Faculty of Veterinary Medicine, University of Warmia and Mazury, Olsztyn, Poland
| | - Joanna Pajdak-Czaus
- Department of Epizootiology, Faculty of Veterinary Medicine, University of Warmia and Mazury, Olsztyn, Poland
| | - Stanisław Robak
- Department of Ichthyology, Hydrobiology and Aquatic Ecology, The Stanislaw Inland Fisheries Institute, Olsztyn, Poland
| | | | - Andrzej K Siwicki
- Department of Microbiology and Clinical Immunology, Faculty of Veterinary Medicine, University of Warmia and Mazury, Olsztyn, Poland
| |
Collapse
|
22
|
Scheuerl T, Cairns J, Becks L, Hiltunen T. Predator coevolution and prey trait variability determine species coexistence. Proc Biol Sci 2019; 286:20190245. [PMID: 31088272 PMCID: PMC6532513 DOI: 10.1098/rspb.2019.0245] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 04/25/2019] [Indexed: 01/08/2023] Open
Abstract
Predation is one of the key ecological mechanisms allowing species coexistence and influencing biological diversity. However, ecological processes are subject to contemporary evolutionary change, and the degree to which predation affects diversity ultimately depends on the interplay between evolution and ecology. Furthermore, ecological interactions that influence species coexistence can be altered by reciprocal coevolution especially in the case of antagonistic interactions such as predation or parasitism. Here we used an experimental evolution approach to test for the role of initial trait variation in the prey population and coevolutionary history of the predator in the ecological dynamics of a two-species bacterial community predated by a ciliate. We found that initial trait variation both at the bacterial and ciliate level enhanced species coexistence, and that subsequent trait evolutionary trajectories depended on the initial genetic diversity present in the population. Our findings provide further support to the notion that the ecology-centric view of diversity maintenance must be reinvestigated in light of recent findings in the field of eco-evolutionary dynamics.
Collapse
Affiliation(s)
- Thomas Scheuerl
- Department of Microbiology, University of Helsinki, PO Box 56, Helsinki 00014, Finland
| | - Johannes Cairns
- Department of Microbiology, University of Helsinki, PO Box 56, Helsinki 00014, Finland
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, PO Box 65, Helsinki 00014Finland
| | - Lutz Becks
- Department of Evolutionary Ecology, Community Dynamics Group, Max Planck Institute for Evolutionary Biology, August Thienemann Strasse 2, 24306 Plön, Germany
- Aquatic Ecology and Evolution, Limnological Institute University Konstanz, Konstanz, Germany
| | - Teppo Hiltunen
- Department of Microbiology, University of Helsinki, PO Box 56, Helsinki 00014, Finland
- Department of Biology, University of Turku, Turku 20014, Finland
| |
Collapse
|
23
|
Aalipour H, Nikbakht A, Etemadi N. Co-inoculation of Arizona cypress with arbuscular mycorrhiza fungi and Pseudomonas fluorescens under fuel pollution. Mycorrhiza 2019; 29:277-289. [PMID: 30900025 DOI: 10.1007/s00572-019-00888-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 03/05/2019] [Indexed: 06/09/2023]
Abstract
Air pollution in metropolitan areas of Iran has negatively impacted establishment, growth, and development of many woody plant species, threatening the health of urban forest species. This study was designed to investigate the effects of artificial inoculation of seedlings of a major urban forest tree, Arizona cypress (Cupressus arizonica Greene) with beneficial microorganisms under the stress of air pollution caused by exhaust emissions from fuel pollutants (FP). We conducted this research as a completely randomized design in a form of split-factorial with three factors comprising arbuscular mycorrhizal fungi (AMF) inoculation with Rhizophagus irregularis or Funneliformis mosseae or a mixture of both species, bacterial inoculation with Pseudomonas fluorescens and non-inoculated controls, and two levels of FP (fuel pollutants and non-fuel pollutants) using three replications of each treatment. Fuel pollutants significantly reduced root colonization, shoot and root dry weight, nutrient concentrations (N, P, K, and Fe), glomalin-related soil protein (GRSP), and chlorophyll concentration, while increasing proline content, enzyme activity, malondialdehyde (MDA), and hydrogen peroxide (H2O2) concentrations in Arizona cypress seedlings. Nevertheless, adverse effects of FP in the inoculated plants (especially AMF plants) were less than in the non-inoculated plants. Inoculations of AMF especially the mixture of both mycorrhizal species effectively alleviated the negative effects of FP on Arizona cypress seedlings. This promising effect was related to increased GRSP content in the media which improved concentrations of N, P, and Fe in plants, enhanced chlorophyll concentration, and elevated enzymatic antioxidants such as ascorbate peroxidase and glutathione peroxidase which resulted in increased dry mass of the plants under air pollution stress.
Collapse
Affiliation(s)
- Hamed Aalipour
- Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan, 8415683111, Iran
| | - Ali Nikbakht
- Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan, 8415683111, Iran.
| | - Nematollah Etemadi
- Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan, 8415683111, Iran
| |
Collapse
|
24
|
Mohamed I, Eid KE, Abbas MHH, Salem AA, Ahmed N, Ali M, Shah GM, Fang C. Use of plant growth promoting Rhizobacteria (PGPR) and mycorrhizae to improve the growth and nutrient utilization of common bean in a soil infected with white rot fungi. Ecotoxicol Environ Saf 2019; 171:539-548. [PMID: 30641315 DOI: 10.1016/j.ecoenv.2018.12.100] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 12/27/2018] [Accepted: 12/29/2018] [Indexed: 06/09/2023]
Abstract
Extensive use of fertilizers and pesticides led to dangerous ecological effects and therefore the biological approaches have been widely recommended to prevent further deterioration for the environment. The current study was conducted to explore the potentiality of using single or combined inoculations by mycorrhizae, Bacillus subtilis and Pseudomonas fluorescence for controlling the infection of common bean plants with Sclerotium rolfsii on one hand and as bio-fertilizers for improving plants nutritional status on the other hand. The soil of study was mildly infected with S. rolfsii and contained high total-P content. Thus, minimal P inputs were added to the inoculated soil in the form of rock phosphate. Activities of plant defense enzymes i.e. chitinase, peroxidase and polyphenol oxidase were determined under the greenhouse conditions and the results obtained herein indicated that activities of such enzymes increased significantly owing to bio-agent inoculations. In this concern, combined treatments resulted in further significant increases over the single ones. A field study was then conducted for two successive years and the results reveal that single inoculations increased straw and green pod yields as well as the uptake of P and Fe by plants as compared with the non-inoculated treatment. Combined inoculants recorded further significant increases in these parameters even when compared with the fungicide treated plants. Generally, straw and pod yields obtained from the second growing season were significantly higher than those attained in the first growing one. Our study confirms the success of the used bio-treatments in minimizing soil pollution through fertilizer and/or pesticide inputs.
Collapse
Affiliation(s)
- Ibrahim Mohamed
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Science, Wuhan 430074, China; Soil and Water Sciences Department, Faculty of Agriculture, Benha University, Egypt; China Program of International Plant Nutrition Institute, Wuhan 430074, China.
| | - Khaled E Eid
- Plant Pathology Department, Faculty of Agriculture, Benha University, Egypt
| | - Mohamed H H Abbas
- Soil and Water Sciences Department, Faculty of Agriculture, Benha University, Egypt
| | - Ahmed A Salem
- Agricultural Microbiology Department, Faculty of Agriculture, Benha University, Egypt
| | - Nevin Ahmed
- Benha University, Benha, Al-Qalyubia Governorate, Egypt
| | - Maha Ali
- Soil and Water Sciences Department, Faculty of Agriculture, Benha University, Egypt
| | - Ghulam Mustafa Shah
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari-campus, Vehari 61100, Pakistan
| | - Chen Fang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Science, Wuhan 430074, China; China Program of International Plant Nutrition Institute, Wuhan 430074, China.
| |
Collapse
|
25
|
Gazzola G, Habimana O, Quinn L, Casey E, Murphy CD. Population dynamics of a dual Pseudomonas putida- Pseudomonas fluorescens biofilm in a capillary bioreactor. Biofouling 2019; 35:299-307. [PMID: 31025575 DOI: 10.1080/08927014.2019.1598397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 02/12/2019] [Accepted: 03/15/2019] [Indexed: 06/09/2023]
Abstract
Most biofilm studies employ single species, yet in nature biofilms exist as mixed cultures, with inevitable effects on growth and development of each species present. To investigate how related species of bacteria interact in biofilms, two Pseudomonas spp., Pseudomonas fluorescens and Pseudomonas putida, were cultured in capillary bioreactors and their growth measured by confocal microscopy and cell counting. When inoculated in pure culture, both bacteria formed healthy biofilms within 72 h with uniform coverage of the surface. However, when the bioreactors were inoculated with both bacteria simultaneously, P. putida was completely dominant after 48 h. Even when the inoculation by P. putida was delayed for 24 h, P. fluorescens was eliminated from the capillary within 48 h. It is proposed that production of the lipopeptide putisolvin by P. putida is the likely reason for the reduction of P. fluorescens. Putisolvin biosynthesis in the dual-species biofilm was confirmed by mass spectrometry.
Collapse
Affiliation(s)
- Giulio Gazzola
- a UCD School of Chemical and Bioprocess Engineering , University College Dublin , Dublin , Ireland
| | - Olivier Habimana
- a UCD School of Chemical and Bioprocess Engineering , University College Dublin , Dublin , Ireland
| | - Laura Quinn
- a UCD School of Chemical and Bioprocess Engineering , University College Dublin , Dublin , Ireland
| | - Eoin Casey
- a UCD School of Chemical and Bioprocess Engineering , University College Dublin , Dublin , Ireland
| | - Cormac D Murphy
- b UCD School of Biomolecular and Biomedical Science , University College Dublin , Dublin , Ireland
| |
Collapse
|
26
|
Ding T, Li T, Li J. Preparation of Coaxial Polylactic Acid-Propyl Gallate Electrospun Fibers and the Effect of Their Coating on Salmon Slices during Chilled Storage. ACS Appl Mater Interfaces 2019; 11:6463-6474. [PMID: 30668113 DOI: 10.1021/acsami.9b00461] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Pseudomonas fluorescens bacteria can grow well in cold-storage conditions and cause food spoilage. Quorum sensing (QS) is a biological pathway existing in a large number of microorganisms, through which bacteria regulate several of their physiological activities. A number of substances have been identified as quorum sensing inhibitors (QSIs); they can interfere with the QS system and control bacterial spoilage characteristics and production of virulence factors. In our previous study, propyl gallate at sub-minimum inhibitory concentration levels showed a potent anti-QS activity. Thus, in this study, coaxial polylactic acid-propyl gallate electrospun fibers were fabricated and their physicochemical properties were characterized. Salmon slices were coated with these electrospun fibers and the effect of this coating on the salmon slices during chilled storage was evaluated. The results showed that the electrospun fibers had a small diameter and smooth surface with no beads or other defects. The thermal stability, tensile strength, and other properties of the fibers were suitable for refrigerated storage conditions. Without inhibiting the bacterial growth in the salmon slices, the QSI-containing electrospun fibers exerted a significant inhibitory effect on the production of total volatile base nitrogen and trimethylamine. Furthermore, the deterioration of muscle tissue in the salmon slices was significantly delayed during cold storage. Quantitative analysis indicated that the electrospun fibers had a significant inhibitory effect on the bacterial spoilage ability. The results suggested that the electrospun fibers loaded with QSIs might be an effective strategy to control food spoilage and enhance the quality of aquatic food products.
Collapse
Affiliation(s)
- Ting Ding
- School of Food Science and Technology , Jiangnan University , Wuxi 214122 , China
| | - Tingting Li
- Key Laboratory of Biotechnology and Bioresources Utilization , Dalian Minzu University, Ministry of Education , Dalian , Liaoning 116600 , China
| | - Jianrong Li
- School of Food Science and Technology , Jiangnan University , Wuxi 214122 , China
- College of Food Science and Technology, Food Safety Key Lab of Liaoning Province, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products , Bohai University , Jinzhou , Liaoning 121013 , China
| |
Collapse
|
27
|
González-Palacios C, Fregeneda-Grandes JM, Aller-Gancedo JM. Biocontrol of saprolegniosis in rainbow trout (Oncorhynchus mykiss Walbaum) using two bacterial isolates (LE89 and LE141) of Pseudomonas fluorescens. J Fish Dis 2019; 42:269-275. [PMID: 30488965 DOI: 10.1111/jfd.12928] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/20/2018] [Accepted: 10/22/2018] [Indexed: 06/09/2023]
Abstract
The probiotic activity of 15 bacterial isolates that inhibit Saprolegnia parasitica in vitro was tested for the biocontrol of saprolegniosis in rainbow trout (Oncorhynchus mykiss Walbaum), adding the bacteria to tank water for 14 days at a concentration of 106 bacteria ml-1 water. Pseudomonas fluorescens LE89 and Pseudomonas fluorescens LE141 were effective in controlling experimental infection with S. parasitica since of the fish treated with LE89, 24.5% ± 16.27% (p < 0.05) became infected, as did 42.8% ± 8.41% (p < 0.05) of those treated with LE141. Given their protective effect when administered in water, their effect was also studied when administered in feed before and after experimental infection. Both bacterial isolates survived low pH levels and the action of bile, grew in skin and intestinal mucus, were resistant to several antibiotics and survived in feed; however, neither of the two isolates prevented S. parasitica infection when administered in feed.
Collapse
|
28
|
Abstract
Predicting evolutionary change poses numerous challenges. Here we take advantage of the model bacterium Pseudomonas fluorescens in which the genotype-to-phenotype map determining evolution of the adaptive 'wrinkly spreader' (WS) type is known. We present mathematical descriptions of three necessary regulatory pathways and use these to predict both the rate at which each mutational route is used and the expected mutational targets. To test predictions, mutation rates and targets were determined for each pathway. Unanticipated mutational hotspots caused experimental observations to depart from predictions but additional data led to refined models. A mismatch was observed between the spectra of WS-causing mutations obtained with and without selection due to low fitness of previously undetected WS-causing mutations. Our findings contribute toward the development of mechanistic models for forecasting evolution, highlight current limitations, and draw attention to challenges in predicting locus-specific mutational biases and fitness effects.
Collapse
Affiliation(s)
- Peter A Lind
- New Zealand Institute for Advanced StudyMassey University at AlbanyAucklandNew Zealand
- Department of Molecular BiologyUmeå UniversityUmeåSweden
| | - Eric Libby
- New Zealand Institute for Advanced StudyMassey University at AlbanyAucklandNew Zealand
- Santa Fe InstituteNew MexicoUnited States
- Department of MathematicsUmeå UniversityUmeåSweden
| | - Jenny Herzog
- New Zealand Institute for Advanced StudyMassey University at AlbanyAucklandNew Zealand
| | - Paul B Rainey
- New Zealand Institute for Advanced StudyMassey University at AlbanyAucklandNew Zealand
- Department of Microbial Population BiologyMax Planck Institute for Evolutionary BiologyPlönGermany
- Ecole Supérieure de Physique et de Chimie Industrielles de la Ville de Paris, ESPCI Paris-TechCNRS UMR 8231, PSL Research UniversityParisFrance
| |
Collapse
|
29
|
Hudek L, Enez A, Bräu L. Cyanobacterial Catalase Activity Prevents Oxidative Stress Induced by Pseudomonas fluorescens DUS1-27 from Inhibiting Brassica napus L. (canola) Growth. Microbes Environ 2018; 33:407-416. [PMID: 30473566 PMCID: PMC6307994 DOI: 10.1264/jsme2.me18061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 10/05/2018] [Indexed: 11/17/2022] Open
Abstract
Plant growth-promoting bacteria (PGPB) inhabit the rhizosphere of plants and are capable of enhancing plant growth through a number of mechanisms. A strain of Pseudomonas fluorescens DUS1-27 was identified as a potential PGPB candidate based on its ability to increase the growth of Brassica napus L. (canola) over that of uninoculated control plants in a soil-based system. The same P. fluorescens isolate was found to reduce plant growth in a hydroponic growth system, with plants showing the symptoms of a microbe-associated molecular pattern (MAMP) response to the bacteria. The amperometric quantification of H2O2, fluorescence-based total peroxidase assays, and quantification of catalase gene expression levels using qRT-PCR revealed that oxidative stress reduced plant growth in the hydroponic system. The addition of the cyanobacterium Nostoc punctiforme (known to have high catalase activity levels) in the hydroponic system as a co-inoculant reduced oxidative stress (49.7% decrease in H2O2 concentrations) triggered by the addition of P. fluorescens DUS1-27, thereby enabling plants to grow larger than uninoculated control plants. These results show the advantage of inoculating with multiple bacteria to promote plant growth and, for the first time, demonstrate that N. punctiforme beneficially assists plants under oxidative stress through its catalase activity in planta.
Collapse
Affiliation(s)
- Lee Hudek
- Deakin University, GeelongAustraliaCentre for Regional and Rural Futures, School of Life and Environmental Sciences
- Deakin University, GeelongAustraliaCentre for Cellular and Molecular Biology, School of Life and Environmental Sciences
| | - Aydin Enez
- Deakin University, GeelongAustraliaCentre for Regional and Rural Futures, School of Life and Environmental Sciences
- Deakin University, GeelongAustraliaCentre for Cellular and Molecular Biology, School of Life and Environmental Sciences
| | - Lambert Bräu
- Deakin University, GeelongAustraliaCentre for Regional and Rural Futures, School of Life and Environmental Sciences
- Deakin University, GeelongAustraliaCentre for Cellular and Molecular Biology, School of Life and Environmental Sciences
| |
Collapse
|
30
|
Hardi EH, Nugroho RA, Kusuma IW, Suwinarti W, Sudaryono A, Rostika R. Borneo herbal plant extracts as a natural medication for prophylaxis and treatment of Aeromonas hydrophila and Pseudomonas fluorescens infection in tilapia ( Oreochromis niloticus). F1000Res 2018; 7:1847. [PMID: 30984371 PMCID: PMC6439779 DOI: 10.12688/f1000research.16902.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/19/2018] [Indexed: 08/15/2023] Open
Abstract
Background: This study aims to describe the antibacterial and immunostimulant abilities of Boesenbergia pandurata (BP), Solanum ferox (SF) and Zingiber Zerumbet (ZZ) plant extracts to treat and prevent Aeromonas hydrophila and Pseudomonas fluorescens infection on Tilapia ( Oreochromis niloticus). Methods: Tilapia (initial weight 15±2 g) were injected intramuscularly (0.1 ml/fish) with a combination of A. hydrophila and P. fluorescens at a density of 1×10 5 CFU ml -1 of each bacteria. Treatment trials were performed at day 7 post-injection with each combined extract, while the prevention trial was performed by including the combined extract into the diet for six and seven days prior to injection. Various combinations of extract-60 ml SF extract/kg feed with 40 ml ZZ/kg feed (SF60/ZZ40), SF50/ZZ50, BP90/SF10, and BP50/SF50-were mixed with a commercial diet and used in both treatment and prevention trials. Haematological and immunological parameters were performed every week for four weeks. Results: In prevention trials, tilapia fed SF50/ZZ50 showed a significant increase of white and red blood cells from weeks 2 to 4. Similarly, significantly increased haematocrit was also found in tilapia fed SF50/ZZ50 in the treatment trial but not in the prevention trial. However, haemoglobin of tilapia in both trials was not affected by any of the various combinations of extract in the diet. Furthermore, phagocytic, respiratory burst, lysozyme activity indexes and survival rate of fish fed with combined extracts were found to be significantly higher than controls. Moreover, the amount of pathogenic bacteria in fish that were fed combined extracts was also lower than the control and was significantly different at week 4. Conclusions: This study indicates that the addition of combined extract into feed has a positive effect on the tilapia's immune system. The SF50/ZZ50 combination appears to improve the innate immune system of tilapia to treat and prevent bacterial infections.
Collapse
Affiliation(s)
- Esti Handayani Hardi
- Microbiology Laboratory, Department of Aquaculture, Faculty of Fisheries and Marine Science, Mulawarman University, Samarinda, East Kalimantan, 75123, Indonesia
| | - Rudy Agung Nugroho
- Animal Physiology, Development and Molecular Laboratory, Department of Biology, Faculty of Mathematics and Natural Sciences, Mulawarman University, Samarinda, East Kalimantan, 75123, Indonesia
| | - Irawan Wijaya Kusuma
- Laboratory of Forest Product Chemistry, Faculty of Forestry, Mulawarman University, Samarinda, East Kalimantan, 75123, Indonesia
| | - Wiwin Suwinarti
- Laboratory of Forest Product Chemistry, Faculty of Forestry, Mulawarman University, Samarinda, East Kalimantan, 75123, Indonesia
| | - Agung Sudaryono
- Department of Aquaculture, Faculty of Fisheries and Marine Science, Diponegoro University, Semarang, Central Java, 50275, Indonesia
| | - Rita Rostika
- Department of Fisheries, Faculty of Fisheries and Marine Science, Padjajaran University, Bandung, West Java, 40600, Indonesia
| |
Collapse
|
31
|
Hüwe C, Schmeichel J, Brodkorb F, Dohlen S, Kalbfleisch K, Kreyenschmidt M, Lorenz R, Kreyenschmidt J. Potential of antimicrobial treatment of linear low-density polyethylene with poly((tert-butyl-amino)-methyl-styrene) to reduce biofilm formation in the food industry. Biofouling 2018; 34:378-387. [PMID: 29663827 DOI: 10.1080/08927014.2018.1453926] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Accepted: 03/12/2018] [Indexed: 06/08/2023]
Abstract
Antimicrobial surfaces are one approach to prevent biofilms in the food industry. The aim of this study was to investigate the effect of poly((tert-butyl-amino)-methyl-styrene) (poly(TBAMS)) incorporated into linear low-density polyethylene (LLDPE) on the formation of mono- and mixed-species biofilms. The biofilm on untreated and treated LLDPE was determined after 48 and 168 h. The comparison of the results indicated that the ability of Listeria monocytogenes to form biofilms was completely suppressed by poly(TBAMS) (Δ168 h 3.2 log10 cfu cm-2) and colonization of Staphylococcus aureus and Escherichia coli was significantly delayed, but no effect on Pseudomonas fluorescens was observed. The results of dual-species biofilms showed complex interactions between the microorganisms, but comparable effects on the individual bacteria by poly(TBAMS) were identified. Antimicrobial treatment with poly(TBAMS) shows great potential to prevent biofilms on polymeric surfaces. However, a further development of the material is necessary to reduce the colonization of strong biofilm formers.
Collapse
Affiliation(s)
- Carina Hüwe
- a Faculty of Agriculture, Institute of Nutritional and Food Sciences, Food Processing Engineering , University of Bonn , Bonn , Germany
| | - Jennifer Schmeichel
- a Faculty of Agriculture, Institute of Nutritional and Food Sciences, Food Processing Engineering , University of Bonn , Bonn , Germany
| | - Florian Brodkorb
- b Department of Chemical Engineering , University of Applied Sciences Münster , Steinfurt , Germany
| | - Sophia Dohlen
- a Faculty of Agriculture, Institute of Nutritional and Food Sciences, Food Processing Engineering , University of Bonn , Bonn , Germany
| | - Katrin Kalbfleisch
- b Department of Chemical Engineering , University of Applied Sciences Münster , Steinfurt , Germany
| | - Martin Kreyenschmidt
- b Department of Chemical Engineering , University of Applied Sciences Münster , Steinfurt , Germany
| | - Reinhard Lorenz
- b Department of Chemical Engineering , University of Applied Sciences Münster , Steinfurt , Germany
| | - Judith Kreyenschmidt
- a Faculty of Agriculture, Institute of Nutritional and Food Sciences, Food Processing Engineering , University of Bonn , Bonn , Germany
| |
Collapse
|
32
|
Nadeem SM, Imran M, Naveed M, Khan MY, Ahmad M, Zahir ZA, Crowley DE. Synergistic use of biochar, compost and plant growth-promoting rhizobacteria for enhancing cucumber growth under water deficit conditions. J Sci Food Agric 2017; 97:5139-5145. [PMID: 28436040 DOI: 10.1002/jsfa.8393] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 04/05/2017] [Accepted: 04/19/2017] [Indexed: 05/18/2023]
Abstract
BACKGROUND Limited information is available about the effectiveness of biochar with plant growth-promoting rhizobacteria (PGPR) and compost. A greenhouse study was conducted to evaluate the effect of biochar in combination with compost and PGPR (Pseudomonas fluorescens) for alleviating water deficit stress. Both inoculated and un-inoculated cucumber seeds were sown in soil treated with biochar, compost and biochar + compost. Three water levels - field capacity (D0), 75% field capacity (D1) and 50% field capacity (D2) - were maintained. RESULTS The results showed that water deficit stress significantly suppressed the growth of cucumber; however, synergistic use of biochar, compost and PGPR mitigated the negative impact of stress. At D2, the synergistic use of biochar, compost and PGPR caused significant increases in shoot length, shoot biomass, root length and root biomass, which were respectively 88, 77, 89 and 74% more than in the un-inoculated control. Significant improvements in chlorophyll and relative water contents as well as reduction in leaf electrolyte leakage demonstrated the effectiveness of this approach. Moreover, the highest population of P. fluorescens was observed where biochar and compost were applied together. CONCLUSION These results suggest that application of biochar with PGPR and/or compost could be an effective strategy for enhancing plant growth under stress. © 2017 Society of Chemical Industry.
Collapse
Affiliation(s)
- Sajid M Nadeem
- University of Agriculture, Faisalabad, Sub-Campus Burewala-Vehari, Pakistan
- Department of Environmental Sciences, University of California Riverside, Riverside, CA, USA
| | - Muhammad Imran
- Department of Environmental Sciences, University of California Riverside, Riverside, CA, USA
- Department of Soil and Environmental Sciences, Muhammad Nawaz Shareef University of Agriculture, Multan, Pakistan
| | - Muhammad Naveed
- Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad, Pakistan
| | - Muhammad Y Khan
- University of Agriculture, Faisalabad, Sub-Campus Burewala-Vehari, Pakistan
| | - Maqshoof Ahmad
- University College of Agriculture and Environmental Sciences, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Zahir A Zahir
- Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad, Pakistan
| | - David E Crowley
- Department of Environmental Sciences, University of California Riverside, Riverside, CA, USA
| |
Collapse
|
33
|
Yadav SK, Singh S, Singh HB, Sarma BK. Compatible Rhizosphere-Competent Microbial Consortium Adds Value to the Nutritional Quality in Edible Parts of Chickpea. J Agric Food Chem 2017; 65:6122-6130. [PMID: 28700827 DOI: 10.1021/acs.jafc.7b01326] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Chickpea is used as a high-energy and protein source in diets of humans and livestock. Moreover, chickpea straw can be used as alternative of forage in ruminant diets. The present study evaluates the effect of beneficial microbial inoculation on enhancing the nutritional values in edible parts of chickpea. Two rhizosphere-competent compatible microbes (Pseudomonas fluorescens OKC and Trichoderma asperellum T42) were selected and applied to seeds either individually or in consortium before sowing. Chickpea seeds treated with the microbes showed enhanced plant growth [88.93% shoot length at 60 days after sowing (DAS)] and biomass accumulation (21.37% at 120 DAS). Notably, the uptake of mineral nutrients, viz., N (90.27, 91.45, and 142.64%), P (14.13, 58.73, and 56.84%), K (20.5, 9.23, and 35.98%), Na (91.98, 101.66, and 36.46%), Ca (16.61, 29.46, and 16%), and organic carbon (28.54, 17.09, and 18.54%), was found in the seed, foliage, and pericarp of the chickpea plants, respectively. Additionally, nutritional quality, viz., total phenolic (59.7, 2.8, and 17.25%), protein (9.78, 18.53, and 7.68%), carbohydrate content (26.22, 30.21, and 26.63%), total flavonoid content (3.11, 9.15, and 7.81%), and reducing power (112.98, 75.42, and 111.75%), was also found in the seed, foliage, and pericarp of the chickpea plants. Most importantly, the microbial-consortium-treated plants showed the maximum increase of nutrient accumulation and enhancement in nutritional quality in all edible parts of chickpea. Nutritional partitioning in different edible parts of chickpea was also evident in the microbial treatments compared to their uninoculated ones. The results thus clearly demonstrated microbe-mediated enhancement in the dietary value of the edible parts of chickpea because seeds are consumed by humans, whereas pericarp and foliage (straw) are used as an alternative of forage and roughage in ruminant diets.
Collapse
Affiliation(s)
- Sudheer K Yadav
- Department of Botany, Institute of Science and ‡Department of Mycology and Plant Pathology, Institute of Agricultural Sciences, Banaras Hindu University , Varanasi, Uttar Pradesh 221005, India
| | - Surendra Singh
- Department of Botany, Institute of Science and ‡Department of Mycology and Plant Pathology, Institute of Agricultural Sciences, Banaras Hindu University , Varanasi, Uttar Pradesh 221005, India
| | - Harikesh B Singh
- Department of Botany, Institute of Science and ‡Department of Mycology and Plant Pathology, Institute of Agricultural Sciences, Banaras Hindu University , Varanasi, Uttar Pradesh 221005, India
| | - Birinchi K Sarma
- Department of Botany, Institute of Science and ‡Department of Mycology and Plant Pathology, Institute of Agricultural Sciences, Banaras Hindu University , Varanasi, Uttar Pradesh 221005, India
| |
Collapse
|
34
|
Yang X, Zhang Q, Chen ZY, Liu H, Li P. Investigation of Pseudomonas fluorescens strain 3JW1 on preventing and reducing aflatoxin contaminations in peanuts. PLoS One 2017; 12:e0178810. [PMID: 28640833 PMCID: PMC5480873 DOI: 10.1371/journal.pone.0178810] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 05/20/2017] [Indexed: 11/19/2022] Open
Abstract
Pseudomonas fluorescens strain 3JW1, which has a broad-spectrum antimicrobial activity, was studied to investigate whether it affects the amounts of aflatoxin B1 (AFB1) produced by Aspergillus flavus. It was found that the bacterium reduced the amounts of AFB1 in potato dextrose broth (PDB) and peanut medium by 97.8% and 99.4%, respectively. It also reduced AFB1 by ~183 μg/kg (55.8%) when applied onto peanut kernels. This strain reduced AFB1 via three mechanisms. First, it significantly inhibited A. flavus growth; second, our data showed that strain 3JW1 inhibits aflatoxin biosynthesis by A. flavus; and third, P. fluorescens strain 3JW1 is capable of degrading AFB1 at a rate as high as 88.3% in 96 hours. This is the first report demonstrating that Pseudomonas fluorescens can reduce toxin contamination caused by A. flavus on peanut kernels. Our findings indicate that P. fluorescens strain 3JW1 had multiple effects including reducing A. flavus infection and aflatoxin contamination. And the results also highlight the potential applications of the strain 3JW1 for the biological control of aflatoxin contamination in peanuts and other susceptible crops.
Collapse
Affiliation(s)
- Xiaona Yang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, P. R. China
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, Nanjing, P. R. China
| | - Qi Zhang
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan, P. R. China
- Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture, Wuhan, P. R. China
- Laboratory of Risk Assessment for Oilseeds Products (Wuhan), Ministry of Agriculture, Wuhan, P. R. China
| | - Zhi-Yuan Chen
- Department of Plant Pathology and Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, United States of America
| | - Hongxia Liu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, P. R. China
- Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, Nanjing, P. R. China
| | - Peiwu Li
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, P. R. China
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan, P. R. China
- Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture, Wuhan, P. R. China
- Laboratory of Risk Assessment for Oilseeds Products (Wuhan), Ministry of Agriculture, Wuhan, P. R. China
| |
Collapse
|
35
|
Khan WU, Ahmad SR, Yasin NA, Ali A, Ahmad A. Effect of Pseudomonas fluorescens RB4 and Bacillus subtilis 189 on the phytoremediation potential of Catharanthus roseus (L.) in Cu and Pb-contaminated soils. Int J Phytoremediation 2017; 19:514-521. [PMID: 27819493 DOI: 10.1080/15226514.2016.1254154] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The remediation of heavy metal-contaminated soils has become a critical issue due to toxic effects of these metals on living organisms. The current research was conducted to study the effect of Pseudomonas fluorescens RB4 and Bacillus subtilis 189 on the growth and phytoremediation potential of Catharanthus roseus in Cu- and Pb-contaminated soils. The bacterial strains exhibited significantly higher level of water-extractable Pb and Cu in Pb, Cu, and Cu+Pb-contaminated. The P. fluorescens RB4 inoculated plants, produced 102%, 48%, and 45% higher fresh weight (FW) in soils contaminated with Cu, Pb, and both elements, respectively, as compared to un-inoculated control plants. Similarly, B. subtilis 189 inoculated plants produced 108%, 43%, and 114% more FW in the presence of Cu, Pb, and both elements. The plants co-cultivated with both bacteria exhibited 121%, 102%, and 177% higher FW, in Cu, Pb, and both elements contaminated soils, as compared to respective un-inoculated control. Co-cultivation of P. fluorescens RB4, B. subtilis 189, and P. fluorescens RB4 + B. subtilis 189 resulted in higher accumulation of Cu and Pb in shoots of the C. roseus grown in contaminated soils as compared to un-inoculated control. Bacterial treatments also improved the translocation and metal bioconcentration factors. The growth and phytoextraction capability of C. roseus was improved by inoculation of P. fluorescens RB4 and B. subtilis 189.
Collapse
Affiliation(s)
- Waheed Ullah Khan
- a College of Earth and Environmental Sciences , University of the Punjab , Lahore , Pakistan
| | - Sajid Rashid Ahmad
- a College of Earth and Environmental Sciences , University of the Punjab , Lahore , Pakistan
| | | | - Aamir Ali
- c Department of Botany , University of Sargodha , Sargodha , Pakistan
| | - Aqeel Ahmad
- d Institute for Medicinal Plants, College of Plant Science and Technology , Huazhong Agricultural University , Wuhan , China
| |
Collapse
|
36
|
Gallique M, Decoin V, Barbey C, Rosay T, Feuilloley MGJ, Orange N, Merieau A. Contribution of the Pseudomonas fluorescens MFE01 Type VI Secretion System to Biofilm Formation. PLoS One 2017; 12:e0170770. [PMID: 28114423 PMCID: PMC5256989 DOI: 10.1371/journal.pone.0170770] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 01/10/2017] [Indexed: 12/16/2022] Open
Abstract
Type VI secretion systems (T6SSs) are widespread in Gram-negative bacteria, including Pseudomonas. These macromolecular machineries inject toxins directly into prokaryotic or eukaryotic prey cells. Hcp proteins are structural components of the extracellular part of this machinery. We recently reported that MFE01, an avirulent strain of Pseudomonas fluorescens, possesses at least two hcp genes, hcp1 and hcp2, encoding proteins playing important roles in interbacterial interactions. Indeed, P. fluorescens MFE01 can immobilise and kill diverse bacteria of various origins through the action of the Hcp1 or Hcp2 proteins of the T6SS. We show here that another Hcp protein, Hcp3, is involved in killing prey cells during co-culture on solid medium. Even after the mutation of hcp1, hcp2, or hcp3, MFE01 impaired biofilm formation by MFP05, a P. fluorescens strain isolated from human skin. These mutations did not reduce P. fluorescens MFE01 biofilm formation, but the three Hcp proteins were required for the completion of biofilm maturation. Moreover, a mutant with a disruption of one of the unique core component genes, MFE01ΔtssC, was unable to produce its own biofilm or inhibit MFP05 biofilm formation. Finally, MFE01 did not produce detectable N-acyl-homoserine lactones for quorum sensing, a phenomenon reported for many other P. fluorescens strains. Our results suggest a role for the T6SS in communication between bacterial cells, in this strain, under biofilm conditions.
Collapse
Affiliation(s)
- Mathias Gallique
- LMSM, Laboratoire de Microbiologie Signaux et Microenvironnement, EA 4312, IUT d'Evreux, Université de Rouen, Normandy University, Evreux, France
| | - Victorien Decoin
- LMSM, Laboratoire de Microbiologie Signaux et Microenvironnement, EA 4312, IUT d'Evreux, Université de Rouen, Normandy University, Evreux, France
| | - Corinne Barbey
- LMSM, Laboratoire de Microbiologie Signaux et Microenvironnement, EA 4312, IUT d'Evreux, Université de Rouen, Normandy University, Evreux, France
- Seeds Innovation Protection Research and Environment (SIPRE), Achicourt, France
| | - Thibaut Rosay
- LMSM, Laboratoire de Microbiologie Signaux et Microenvironnement, EA 4312, IUT d'Evreux, Université de Rouen, Normandy University, Evreux, France
| | - Marc G. J. Feuilloley
- LMSM, Laboratoire de Microbiologie Signaux et Microenvironnement, EA 4312, IUT d'Evreux, Université de Rouen, Normandy University, Evreux, France
| | - Nicole Orange
- LMSM, Laboratoire de Microbiologie Signaux et Microenvironnement, EA 4312, IUT d'Evreux, Université de Rouen, Normandy University, Evreux, France
| | - Annabelle Merieau
- LMSM, Laboratoire de Microbiologie Signaux et Microenvironnement, EA 4312, IUT d'Evreux, Université de Rouen, Normandy University, Evreux, France
- * E-mail:
| |
Collapse
|
37
|
Rodríguez-López P, Carballo-Justo A, Draper LA, Cabo ML. Removal of Listeria monocytogenes dual-species biofilms using combined enzyme-benzalkonium chloride treatments. Biofouling 2017; 33:45-58. [PMID: 27918204 DOI: 10.1080/08927014.2016.1261847] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 11/08/2016] [Indexed: 06/06/2023]
Abstract
The effects of pronase (PRN), cellulase (CEL) or DNaseI alone or combined with benzalkonium chloride (BAC) against Listeria monocytogenes-carrying biofilms were assayed. The best removal activity against L. monocytogenes-Escherichia coli biofilms was obtained using DNaseI followed by PRN and CEL. Subsequently, a modified logistic model was used to quantify the combined effects of PRN or DNaseI with BAC. A better BAC performance after PRN compared to DNaseI eradicating L. monocytogenes was observed. In E. coli the effects were the opposite. Finally, effects of DNaseI and DNaseI-BAC treatments were compared against two different L. monocytogenes-carrying biofilms. DNaseI-BAC was more effective against L. monocytogenes when co-cultured with E. coli. Nonetheless, comparing the removal effects after BAC addition, these were higher in mixed-biofilms with Pseudomonas fluorescens. However, a high number of released viable cells was observed after combined treatments. These results open new perspectives of enzymes as an anti-biofilm strategy for environmental pathogen control.
Collapse
Affiliation(s)
- Pedro Rodríguez-López
- a Department of Microbiology and Technology of Marine Products , Instituto de Investigaciones Marinas (IIM-CSIC) , Pontevedra , Spain
- b Faculty of Biosciences, Department of Genetics and Microbiology , Autonomous University of Barcelona , Catalonia , Spain
| | - Alba Carballo-Justo
- a Department of Microbiology and Technology of Marine Products , Instituto de Investigaciones Marinas (IIM-CSIC) , Pontevedra , Spain
| | - Lorraine A Draper
- c APC Microbiome Institute , University College Cork , Cork , Ireland
| | - Marta L Cabo
- a Department of Microbiology and Technology of Marine Products , Instituto de Investigaciones Marinas (IIM-CSIC) , Pontevedra , Spain
| |
Collapse
|
38
|
Ramachandran SR, Yin C, Kud J, Tanaka K, Mahoney AK, Xiao F, Hulbert SH. Effectors from Wheat Rust Fungi Suppress Multiple Plant Defense Responses. Phytopathology 2017; 107:75-83. [PMID: 27503371 DOI: 10.1094/phyto-02-16-0083-r] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Fungi that cause cereal rust diseases (genus Puccinia) are important pathogens of wheat globally. Upon infection, the fungus secretes a number of effector proteins. Although a large repository of putative effectors has been predicted using bioinformatic pipelines, the lack of available high-throughput effector screening systems has limited functional studies on these proteins. In this study, we mined the available transcriptomes of Puccinia graminis and P. striiformis to look for potential effectors that suppress host hypersensitive response (HR). Twenty small (<300 amino acids), secreted proteins, with no predicted functions were selected for the HR suppression assay using Nicotiana benthamiana, in which each of the proteins were transiently expressed and evaluated for their ability to suppress HR caused by four cytotoxic effector-R gene combinations (Cp/Rx, ATR13/RPP13, Rpt2/RPS-2, and GPA/RBP-1) and one mutated R gene-Pto(Y207D). Nine out of twenty proteins, designated Shr1 to Shr9 (suppressors of hypersensitive response), were found to suppress HR in N. benthamiana. These effectors varied in the effector-R gene defenses they suppressed, indicating these pathogens can interfere with a variety of host defense pathways. In addition to HR suppression, effector Shr7 also suppressed PAMP-triggered immune response triggered by flg22. Finally, delivery of Shr7 through Pseudomonas fluorescens EtHAn suppressed nonspecific HR induced by Pseudomonas syringae DC3000 in wheat, confirming its activity in a homologous system. Overall, this study provides the first evidence for the presence of effectors in Puccinia species suppressing multiple plant defense responses.
Collapse
Affiliation(s)
- Sowmya R Ramachandran
- First, second, fourth, fifth, and seventh authors: Department of Plant Pathology, Washington State University, Pullman, WA 99164-6430; and third and sixth authors: Plant, Soil and Entomological Sciences, University of Idaho, Moscow, ID 83844-2339
| | - Chuntao Yin
- First, second, fourth, fifth, and seventh authors: Department of Plant Pathology, Washington State University, Pullman, WA 99164-6430; and third and sixth authors: Plant, Soil and Entomological Sciences, University of Idaho, Moscow, ID 83844-2339
| | - Joanna Kud
- First, second, fourth, fifth, and seventh authors: Department of Plant Pathology, Washington State University, Pullman, WA 99164-6430; and third and sixth authors: Plant, Soil and Entomological Sciences, University of Idaho, Moscow, ID 83844-2339
| | - Kiwamu Tanaka
- First, second, fourth, fifth, and seventh authors: Department of Plant Pathology, Washington State University, Pullman, WA 99164-6430; and third and sixth authors: Plant, Soil and Entomological Sciences, University of Idaho, Moscow, ID 83844-2339
| | - Aaron K Mahoney
- First, second, fourth, fifth, and seventh authors: Department of Plant Pathology, Washington State University, Pullman, WA 99164-6430; and third and sixth authors: Plant, Soil and Entomological Sciences, University of Idaho, Moscow, ID 83844-2339
| | - Fangming Xiao
- First, second, fourth, fifth, and seventh authors: Department of Plant Pathology, Washington State University, Pullman, WA 99164-6430; and third and sixth authors: Plant, Soil and Entomological Sciences, University of Idaho, Moscow, ID 83844-2339
| | - Scot H Hulbert
- First, second, fourth, fifth, and seventh authors: Department of Plant Pathology, Washington State University, Pullman, WA 99164-6430; and third and sixth authors: Plant, Soil and Entomological Sciences, University of Idaho, Moscow, ID 83844-2339
| |
Collapse
|
39
|
Viollet A, Pivato B, Mougel C, Cleyet-Marel JC, Gubry-Rangin C, Lemanceau P, Mazurier S. Pseudomonas fluorescens C7R12 type III secretion system impacts mycorrhization of Medicago truncatula and associated microbial communities. Mycorrhiza 2017; 27:23-33. [PMID: 27549437 DOI: 10.1007/s00572-016-0730-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 08/11/2016] [Indexed: 05/20/2023]
Abstract
Type three secretion systems (T3SSs) mediate cell-to-cell interactions between Gram-negative bacteria and eukaryotes. We hypothesized that fluorescent pseudomonads harboring T3SS (T3SS+) would be beneficial to arbuscular mycorrhizal symbiosis because non-pathogenic fluorescent pseudomonads have been previously shown to be much more abundant in mycorrhizal than in non-mycorrhizal roots. We tested this hypothesis by comparing mycorrhization and the associated rhizosphere microbial communities of Medicago truncatula grown in a non-sterile soil inoculated with either the T3SS+ mycorrhiza helper bacterium Pseudomonas fluorescens (C7R12) or a T3SS- mutant of the strain. Results showed that the bacterial secretion system was responsible for the promotion of mycorrhization because root colonization by arbuscular mycorrhizal fungi was not promoted by the T3SS- mutant. The observed T3SS-mediated promotion of mycorrhization was associated with changes in the rhizosphere bacterial communities and the increased occurrence of Claroidoglomeraceae within the intraradical arbuscular mycorrhizal fungi. Furthermore, both pseudomonad strains promoted the host-free growth of a model arbuscular mycorrhizal fungus in vitro, suggesting that T3SS-mediated promotion of mycorrhization occurs during plant-fungal interactions rather than during the pre-symbiotic phase of fungal growth. Taken together, these data provide evidence for the involvement of T3SS in promoting arbuscular mycorrhization by a model fluorescent pseudomonad and suggest the implication of interactions between the bacterium and mycorrhizas.
Collapse
Affiliation(s)
- Amandine Viollet
- Agroécologie, AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, 21000, Dijon, France
| | - Barbara Pivato
- Agroécologie, AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, 21000, Dijon, France
| | - Christophe Mougel
- Agroécologie, AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, 21000, Dijon, France
- INRA, UMR1349 IGEPP, 35653, Le Rheu, France
| | - Jean-Claude Cleyet-Marel
- INRA, UMR 113 'Laboratoire des Symbioses Tropicales et Méditerranéennes', Campus International de Baillarguet, TA-A82/J, 34398, Montpellier Cedex 5, France
| | - Cécile Gubry-Rangin
- INRA, UMR 113 'Laboratoire des Symbioses Tropicales et Méditerranéennes', Campus International de Baillarguet, TA-A82/J, 34398, Montpellier Cedex 5, France
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 3UU, UK
| | - Philippe Lemanceau
- Agroécologie, AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, 21000, Dijon, France
| | - Sylvie Mazurier
- Agroécologie, AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, 21000, Dijon, France.
| |
Collapse
|
40
|
Overney A, Jacques-André-Coquin J, Ng P, Carpentier B, Guillier L, Firmesse O. Impact of environmental factors on the culturability and viability of Listeria monocytogenes under conditions encountered in food processing plants. Int J Food Microbiol 2016; 244:74-81. [PMID: 28073080 DOI: 10.1016/j.ijfoodmicro.2016.12.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 12/15/2016] [Accepted: 12/19/2016] [Indexed: 01/01/2023]
Abstract
The ability of Listeria monocytogenes to adhere to and persist on surfaces for months or even years may be responsible for its transmission from contaminated surfaces to food products. Hence the necessity to find effective means to prevent the establishment of L. monocytogenes in food processing environments. The aim of this study was to assess, through a fractional experimental design, the environmental factors that could affect the survival of L. monocytogenes cells on surfaces to thereby prevent the persistence of this pathogen in conditions mimicking those encountered in food processing plants: culture with smoked salmon juice or meat exudate, use of two materials with different hygiene status, biofilm of L. monocytogenes in pure-culture or dual-culture with a Pseudomonas fluorescens strain, application of a drying step after cleaning and disinfection (C&D) and comparison of two strains of L. monocytogenes. Bacterial survival was assessed by culture, qPCR to quantify total cells, and propidium monoazide coupled with qPCR to quantify viable cells and highlight viable but non-culturable (VBNC) cells. Our results showed that failure to apply C&D causes cell persistence on surfaces. Moreover, the sanitation procedure leads only to a loss of culturability and appearance of VBNC populations. However, an additional daily drying step after C&D optimises the effectiveness of these procedures to reduce culturable populations. Our results reinforce the importance to use molecular tools to monitor viable pathogens in food processing plants to avoid underestimating the amounts of cells using only methods based on cell culture.
Collapse
Affiliation(s)
- Anaïs Overney
- Université Paris-Est, Anses, Laboratory for Food Safety, 94701 Maisons-Alfort, France
| | | | - Patricia Ng
- Université Paris-Est, Anses, Laboratory for Food Safety, 94701 Maisons-Alfort, France
| | - Brigitte Carpentier
- Université Paris-Est, Anses, Laboratory for Food Safety, 94701 Maisons-Alfort, France
| | - Laurent Guillier
- Université Paris-Est, Anses, Laboratory for Food Safety, 94701 Maisons-Alfort, France
| | - Olivier Firmesse
- Université Paris-Est, Anses, Laboratory for Food Safety, 94701 Maisons-Alfort, France.
| |
Collapse
|
41
|
Cooley RB, O’Donnell JP, Sondermann H. Coincidence detection and bi-directional transmembrane signaling control a bacterial second messenger receptor. eLife 2016; 5:e21848. [PMID: 28001128 PMCID: PMC5231407 DOI: 10.7554/elife.21848] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 12/20/2016] [Indexed: 12/15/2022] Open
Abstract
The second messenger c-di-GMP (or cyclic diguanylate) regulates biofilm formation, a physiological adaptation process in bacteria, via a widely conserved signaling node comprising a prototypical transmembrane receptor for c-di-GMP, LapD, and a cognate periplasmic protease, LapG. Previously, we reported a structure-function study of a soluble LapD•LapG complex, which established conformational changes in the receptor that lead to c-di-GMP-dependent protease recruitment (Chatterjee et al., 2014). This work also revealed a basal affinity of c-di-GMP-unbound receptor for LapG, the relevance of which remained enigmatic. Here, we elucidate the structural basis of coincidence detection that relies on both c-di-GMP and LapG binding to LapD for receptor activation. The data indicate that high-affinity for LapG relies on the formation of a receptor dimer-of-dimers, rather than a simple conformational change within dimeric LapD. The proposed mechanism provides a rationale of how external proteins can regulate receptor function and may also apply to c-di-GMP-metabolizing enzymes that are akin to LapD.
Collapse
Affiliation(s)
- Richard B Cooley
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, United States
| | - John P O’Donnell
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, United States
| | - Holger Sondermann
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, United States
| |
Collapse
|
42
|
Albano LJ, Macfie SM. Investigating the ability of Pseudomonas fluorescens UW4 to reduce cadmium stress in Lactuca sativa via an intervention in the ethylene biosynthetic pathway. Can J Microbiol 2016; 62:1057-1062. [PMID: 27759425 DOI: 10.1139/cjm-2016-0315] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
A typical plant response to any biotic or abiotic stress, including cadmium (Cd), involves increased ethylene synthesis, which causes senescence of the affected plant part. Stressed plants can experience reduced ethylene and improved growth if they are inoculated with bacteria that have the enzyme ACC deaminase, which metabolizes the ethylene precursor ACC (1-aminocyclopropane-1-carboxylate). We investigated whether one such bacterium, Pseudomonas fluorescens UW4, reduces the production of ethylene and improves the growth of lettuce (Lactuca sativa) sown in Cd-contaminated potting material (PRO-MIX® BX). Plants were inoculated with the wild-type P. fluorescens UW4 or a mutant strain that cannot produce ACC deaminase. Cadmium-treated plants contained up to 50 times more Cd than did control plants. In noninoculated plants, Cd induced a 5-fold increase in ethylene concentration. The wild-type bacterium prevented Cd-induced reductions in root biomass but there was no relationship between Cd treatment and ethylene production in inoculated plants. In contrast, when the concentration of ethylene was plotted against the extent of bacterial colonization of the roots, increased colonization with wild-type P. fluorescens UW4 was associated with 20% less ethylene production. Ours is the first study to show that the protective effect of this bacterium is proportional to the quantity of bacteria on the root surface.
Collapse
Affiliation(s)
- Lucas J Albano
- Department of Biology, University of Western Ontario, London, ON N6A 5B7, Canada
- Department of Biology, University of Western Ontario, London, ON N6A 5B7, Canada
| | - Sheila M Macfie
- Department of Biology, University of Western Ontario, London, ON N6A 5B7, Canada
- Department of Biology, University of Western Ontario, London, ON N6A 5B7, Canada
| |
Collapse
|
43
|
Zhou JY, Li X, Zhao D, Deng-Wang MY, Dai CC. Reactive oxygen species and hormone signaling cascades in endophytic bacterium induced essential oil accumulation in Atractylodes lancea. Planta 2016; 244:699-712. [PMID: 27125387 DOI: 10.1007/s00425-016-2536-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 04/15/2016] [Indexed: 05/20/2023]
Abstract
Pseudomonas fluorescens induces gibberellin and ethylene signaling via hydrogen peroxide in planta . Ethylene activates abscisic acid signaling. Hormones increase sesquiterpenoid biosynthesis gene expression and enzyme activity, inducing essential oil accumulation. Atractylodes lancea is a famous Chinese medicinal plant, whose main active components are essential oils. Wild A. lancea has become endangered due to habitat destruction and over-exploitation. Although cultivation can ensure production of the medicinal material, the essential oil content in cultivated A. lancea is significantly lower than that in the wild herb. The application of microbes as elicitors has become an effective strategy to increase essential oil accumulation in cultivated A. lancea. Our previous study identified an endophytic bacterium, Pseudomonas fluorescens ALEB7B, which can increase essential oil accumulation in A. lancea more efficiently than other endophytes; however, the underlying mechanisms remain unknown (Physiol Plantarum 153:30-42, 2015; Appl Environ Microb 82:1577-1585, 2016). This study demonstrates that P. fluorescens ALEB7B firstly induces hydrogen peroxide (H2O2) signaling in A. lancea, which then simultaneously activates gibberellin (GA) and ethylene (ET) signaling. Subsequently, ET activates abscisic acid (ABA) signaling. GA and ABA signaling increase expression of HMGR and DXR, which encode key enzymes involved in sesquiterpenoid biosynthesis, leading to increased levels of the corresponding enzymes and then an accumulation of essential oils. Specific reactive oxygen species and hormone signaling cascades induced by P. fluorescens ALEB7B may contribute to high-efficiency essential oil accumulation in A. lancea. Illustrating the regulation mechanisms underlying P. fluorescens ALEB7B-induced essential oil accumulation not only provides the theoretical basis for the inducible synthesis of terpenoids in many medicinal plants, but also further reveals the complex and diverse interactions among different plants and their endophytes.
Collapse
Affiliation(s)
- Jia-Yu Zhou
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, Jiangsu, China
| | - Xia Li
- Jiangsu High Quality Rice Research and Development Center, Nanjing Branch of China National Center Rice Improvement, Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, Jiangsu, China
| | - Dan Zhao
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, Jiangsu, China
| | - Meng-Yao Deng-Wang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, Jiangsu, China
| | - Chuan-Chao Dai
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, Jiangsu, China.
| |
Collapse
|
44
|
Kaur R, Joshi N, Virk JS, Sharma S. Evaluation of Pseudomonas fluorescens for the management of tomato early blight disease and fruit borer. J Environ Biol 2016; 37:869-872. [PMID: 29251469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Early blight disease and fruit damage by Helicoverpa armigera are serious problems of tomato causing heavy losses in the yield. An experiment was conducted to evaluate the efficacy of talc based formulation of antagonist Pseudomonas flourescens (Psf) delivered through two different forms of substrate, farmyard manure (FYM) and vermicompost, for the management of tomato early blight disease. Two treatments of Psf, were selected Solarization of nursery soil + seeds and seedlings root dip treatment with Psf formulation + Use of FYM colonized with Psf formulation; Solarization of nursery soil + seed and seedlings root dip treatment with Psf formulation + Use of vermicompost colonized with Psf formulation. These were compared with farmer's practice and untreated control. The impact of all these treatments on tomato fruit borer, H. armigera was also studied. There was not much variation in plant growth parameters (plant height and canopy width) between all the treatments. Both biocontrol treatments (17.69% and 141.3 q acre-1; 15.70% and 139.4 q acre-1, respectively), as well as farmer's practice (10.25% and 208.5 q acre-1) were found to be better than untreated control (29.21% and 94.6 q acre-1) in reducing the incidence of early blight disease in tomato and increasing the marketable yield of tomato fruits. However, the farmer's practice was found to be significantly better than both biocontrol treatments of Psf in controlling fruit damage due to disease, as well as fruit borer. The effect of both bioagents enriched formulations i.e. FYM+Psf and vermicompost+Psf with respect to disease was significantly at par with each other, whereas they had no impact on the fruit borer incidence. The results indicated that either of biocontrol treatments of P. flourescens using farmyard manure and vermicompost, as delivery substrates, can be considered as one of the component along with chemical control in developing IPM programme for the management of early blight disease in tomato.
Collapse
|
45
|
Arseneault T, Goyer C, Filion M. Biocontrol of Potato Common Scab is Associated with High Pseudomonas fluorescens LBUM223 Populations and Phenazine-1-Carboxylic Acid Biosynthetic Transcript Accumulation in the Potato Geocaulosphere. Phytopathology 2016; 106:963-70. [PMID: 27088392 DOI: 10.1094/phyto-01-16-0019-r] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Pseudomonads are often used as biocontrol agents because they display a broad range of mechanisms to control diseases. Common scab of potato, caused by Streptomyces scabies, was previously reported to be controlled by Pseudomonas fluorescens LBUM223 through phenazine-1-carboxylic acid (PCA) production. In this study, we aimed at characterizing the population dynamics of LBUM223 and the expression of phzC, a key gene involved in the biosynthesis of PCA, in the rhizosphere and geocaulosphere of potato plants grown under controlled and field conditions. Results obtained from controlled experiments showed that soil populations of LBUM223 significantly declined over a 15-week period. However, at week 15, the presence of S. scabies in the geocaulosphere was associated with significantly higher populations of LBUM223 than when the pathogen was absent. It also led to the detection of significantly higher phzC gene transcript numbers. Under field conditions, soil populations of LBUM223 followed a similar decline in time when a single inoculation was applied in spring but remained stable when reinoculated biweekly, which also led to greater phzC gene transcripts accumulation. Taken together, our findings suggest that LBUM223 must colonize the potato geocaulosphere at high levels (10(7) bacteria/g of soil) in order to achieve biocontrol of common scab through increased PCA production.
Collapse
Affiliation(s)
- Tanya Arseneault
- First and third authors: Université de Moncton, Department of Biology, Moncton, NB, Canada; first author: University of Reading, School of Biological Sciences, Reading, UK; and second author: Potato Research Center, Agriculture and Agri-Food Canada, Fredericton, NB, Canada
| | - Claudia Goyer
- First and third authors: Université de Moncton, Department of Biology, Moncton, NB, Canada; first author: University of Reading, School of Biological Sciences, Reading, UK; and second author: Potato Research Center, Agriculture and Agri-Food Canada, Fredericton, NB, Canada
| | - Martin Filion
- First and third authors: Université de Moncton, Department of Biology, Moncton, NB, Canada; first author: University of Reading, School of Biological Sciences, Reading, UK; and second author: Potato Research Center, Agriculture and Agri-Food Canada, Fredericton, NB, Canada
| |
Collapse
|
46
|
Deveau A, Gross H, Palin B, Mehnaz S, Schnepf M, Leblond P, Dorrestein PC, Aigle B. Role of secondary metabolites in the interaction between Pseudomonas fluorescens and soil microorganisms under iron-limited conditions. FEMS Microbiol Ecol 2016; 92:fiw107. [PMID: 27199346 PMCID: PMC5975829 DOI: 10.1093/femsec/fiw107] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 02/15/2016] [Accepted: 05/15/2016] [Indexed: 01/18/2023] Open
Abstract
Microorganisms can be versatile in their interactions with each other, being variously beneficial, neutral or antagonistic in their effect. Although this versatility has been observed among many microorganisms and in many environments, little is known regarding the mechanisms leading to these changes in behavior. In the present work, we analyzed the mechanism by which the soil bacterium Pseudomonas fluorescens BBc6R8 shifts from stimulating the growth of the ectomycorrhizal fungus Laccaria bicolor S238N to killing the fungus. We show that among the three secondary metabolites produced by the bacterial strain-the siderophores enantio-pyochelin and pyoverdine, and the biosurfactant viscosin-the siderophores are mainly responsible for the antagonistic activity of the bacterium under iron-limited conditions. While the bacterial strain continues to produce beneficial factors, their effects are overridden by the action of their siderophores. This antagonistic activity of the strain P. fluorescens BBC6R8 in iron-depleted environments is not restricted to its influence on L. bicolor, since it was also seen to inhibit the growth of the actinomycete Streptomyces ambofaciens ATCC23877. We show that the strain P. fluorescens BBc6R8 uses different strategies to acquire iron, depending on certain biotic and abiotic factors.
Collapse
Affiliation(s)
- Aurélie Deveau
- INRA, Interactions Arbres-Microorganismes, UMR1136, Université de Lorraine, F-54280 Champenoux, France
| | - Harald Gross
- Department of Pharmaceutical Biology, Pharmaceutical Institute, University of Tuebingen, Auf der Morgenstelle 8, 72076 Tuebingen, Germany
| | - Béatrice Palin
- INRA, Interactions Arbres-Microorganismes, UMR1136, Université de Lorraine, F-54280 Champenoux, France
| | - Samina Mehnaz
- Department of Pharmaceutical Biology, Pharmaceutical Institute, University of Tuebingen, Auf der Morgenstelle 8, 72076 Tuebingen, Germany Department of Biological Sciences, Forman Christian College, Ferozepur Road, Lahore 54600, Pakistan
| | - Max Schnepf
- Department of Pharmaceutical Biology, Pharmaceutical Institute, University of Tuebingen, Auf der Morgenstelle 8, 72076 Tuebingen, Germany
| | - Pierre Leblond
- Dynamique des Génomes et Adaptation Microbienne, UMR1128, Université de Lorraine, Faculté des Sciences et Technologies-Campus Aiguillettes, Vandœuvre-lès-Nancy, F-54506, France
| | - Pieter C Dorrestein
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, CA 92093, USA
| | - Bertrand Aigle
- Dynamique des Génomes et Adaptation Microbienne, UMR1128, Université de Lorraine, Faculté des Sciences et Technologies-Campus Aiguillettes, Vandœuvre-lès-Nancy, F-54506, France
| |
Collapse
|
47
|
Abstract
The classical, ecological, paradox of enrichment describes a phenomenon that resource enrichment destabilizes predator-prey systems by exacerbating population oscillations. Here we suggest a new, evolutionary, paradox of enrichment. Resource enrichment can lead to more asymmetrical predator-prey coevolution (i.e., extremely high levels of prey defenses against predators) that decreases predator abundances and increases predator extinction risk. A major reason for this is that high resource availability can reduce fitness costs associated with prey defenses. In our experiments with a bacterium and its lytic phage, nutrient-balanced resource enrichment led to patterns in population demography and coevolutionary dynamics consistent with this coevolution-based paradox of enrichment; in particular, phage population extinction events were observed under nutrient-rich, not nutrient-poor, conditions. Consistent with ecological studies, carbon-biased resource enrichment (with carbon availability disproportionately increased relative to other nutrients) did not destabilize dynamics, and the asymmetry of coevolution was not altered in this context. Our work highlights the importance of integrating ecological and evolutionary thinking for studies of the consequences of nutrient pollution and other types of environmental changes.
Collapse
|
48
|
Keshavarz-Tohid V, Taheri P, Taghavi SM, Tarighi S. The role of nitric oxide in basal and induced resistance in relation with hydrogen peroxide and antioxidant enzymes. J Plant Physiol 2016; 199:29-38. [PMID: 27302004 DOI: 10.1016/j.jplph.2016.05.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Revised: 05/04/2016] [Accepted: 05/06/2016] [Indexed: 05/10/2023]
Abstract
Nitric oxide (NO) is one of the main signal molecules, which is involved in plant growth and development and can change regular physiological activity in biotic and abiotic stresses. In this study, the role of NO in induced resistance with Pseudomonas fluorescent (CHA0) and basal resistance against Rhizoctonia solani in bean plant was investigated. Our results revealed that P. fluorescent and R. solani can increase NO production at 6h post inoculation (hpi). Also, using the NO donor S-nitroso-N-acetyl D-penicillamine (SNAP) led to increase NO and bean plant resistance against R. solani. Utilizing the NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethy-limidazoline-1-oxyl-3-oxide (cPTIO), not only decreased basal resistance but also reduced induced resistance. In continue, the activity of antioxidant enzymes was studied in the former treatments. SNAP, CHA0 and R. solani increased the activity of peroxidase (POX), catalase (CAT) and ascorbate peroxidase (APX) at 6, 12 and 24h post inoculation (hpi). In contrast, using cPTIO and R. solani simultaneously (cPTIO+R) showed reduction in activity of POX and APX at 6 hpi. The cPTIO+R treatment increased POX, APX and CAT activity at 12 and 24 hpi. Hydrogen peroxide (H2O2) monitoring in the leaf discs clarified that SNAP can increase H2O2 production like CHA0 and R. solani. On the other hand, SNAP increased the resistance level of leaf discs against R. solani. Treating the leaf discs with cPTIO led to decrease resistance against the pathogen. These leaf discs showed reduction in H2O2 production at 6 hpi and suddenly enhanced H2O2 generation was observed at 24hpi. This study showed that CHA0 can increase NO level in bean plants. NO induced H2O2 generation and regulated redox state of the host plant. This interaction resulted in significant defense against the pathogen.
Collapse
Affiliation(s)
- Vahid Keshavarz-Tohid
- Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Parissa Taheri
- Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran.
| | - Seyed Mohsen Taghavi
- Department of Plant Protection, Faculty of Agriculture, Shiraz University, Shiraz, Iran
| | - Saeed Tarighi
- Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
| |
Collapse
|
49
|
Akter S, Kadir J, Juraimi AS, Saud HM. In vitro evaluation of Pseudomonas bacterial isolates from rice phylloplane for biocontrol of Rhizoctonia solani and plant growth promoting traits. J Environ Biol 2016; 37:597-602. [PMID: 27498507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The ability for biocontrol and plant growth promotion of three Pseudomonas bacterial isolates namely Pseudomonas fluorescens (UMB20), Pseudomonas aeruginosa (KMB25) and Pseudomonas asplenii (BMB42) obtained from rice plants was investigated. Fungal growth inhibition by the isolates ranged from 86.85 to 93.15% in volatile and 100% in diffusible metabolites test. Among the isolates, BMB42 showed fungal growth inhibition significantly in the volatile metabolite test. Isolates UMB20 and BMB42 were able to synthesis chitinase with chitinolytic indices of 13.66 and 13.50, respectively. In case of -1,3-glucanase, all the isolates showed activity to produce this enzyme at varied levels and isolate KMB25 showed significantly highest activity (53.53 ppm). Among the three isolates, KMB25 showed positive response to protease production and all of them were negative to pectinase and lipase and positive to the production of siderophore, and HCN, and were able to solubilize tricalcium phosphate. All the three bacterial isolates were capable of forming biofilm at different levels. Above results suggest that phylloplane Pseudomonas bacterial isolates have potential for antifungal activities and plant growth promotion.
Collapse
|
50
|
Begum SS, Radha KV. Comparative Kinetic Studies and Performance Evaluation of Biofilm and Biomass Characteristics of Pseudomonas fluorescens in Degrading Synthetic Phenolic Effluent in Inverse Fluidized Bed Biofilm Reactor. Water Environ Res 2016; 88:415-424. [PMID: 27131305 DOI: 10.2175/106143016x14504669768417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The bioremediation potential of Pseudomonas fluorescens was studied in an Inverse Fluidized Bed Biofilm Reactor under batch recirculation conditions using synthetic phenolic effluent of various concentrations (400, 600, 800, 1000 and 1200 mg/l). The performance of the reactor was investigated and the characteristics of biomass and biofilm were determined by evaluating biofilm dry density and thickness, bioparticle density, suspended and attached biomass concentration, chemical oxygen demand and phenol removal efficiency. Biodegradation kinetics had been studied for suspended biomass culture and biofilm systems with respect to its specific growth and substrate consumption rates. Suspended biomass followed substrate inhibition kinetics and the experimental data fitted well with the Haldane model. The degradation kinetic behavior of biofilm revealed that a well adapted biofilm system with effective control of biofilm thickness in an inverse fluidized bed biofilm reactor overcomes substrate inhibition effects by tolerating higher phenol concentration and fitted well to the Monod model.
Collapse
Affiliation(s)
- S Sabarunisha Begum
- Department of Biotechnology, Rajalakshmi Engineering College, Thandalam, Chennai - 602105, Tamil Nadu, India
| | | |
Collapse
|