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Liang J, Tang M, Chen L, Wang W, Liang X. Oxidative stress resistance prompts pyrroloquinoline quinone biosynthesis in Hyphomicrobium denitrificans H4-45. Appl Microbiol Biotechnol 2024; 108:204. [PMID: 38349428 PMCID: PMC10864529 DOI: 10.1007/s00253-024-13053-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 01/26/2024] [Accepted: 02/03/2024] [Indexed: 02/15/2024]
Abstract
Pyrroloquinoline quinone (PQQ) is a natural antioxidant with diverse applications in food and pharmaceutical industries. A lot of effort has been devoted toward the discovery of PQQ high-producing microbial species and characterization of biosynthesis, but it is still challenging to achieve a high PQQ yield. In this study, a combined strategy of random mutagenesis and adaptive laboratory evolution (ALE) with fermentation optimization was applied to improve PQQ production in Hyphomicrobium denitrificans H4-45. A mutant strain AE-9 was obtained after nearly 400 generations of UV-LiCl mutagenesis, followed by an ALE process, which was conducted with a consecutive increase of oxidative stress generated by kanamycin, sodium sulfide, and potassium tellurite. In the flask culture condition, the PQQ production in mutant strain AE-9 had an 80.4% increase, and the cell density increased by 14.9% when compared with that of the initial strain H4-45. Moreover, batch and fed-batch fermentation processes were optimized to further improve PQQ production by pH control strategy, methanol and H2O2 feed flow, and segmented fermentation process. Finally, the highest PQQ production and productivity of the mutant strain AE-9 reached 307 mg/L and 4.26 mg/L/h in a 3.7-L bioreactor, respectively. Whole genome sequencing analysis showed that genetic mutations in the ftfL gene and thiC gene might contribute to improving PQQ production by enhancing methanol consumption and cell growth in the AE-9 strain. Our study provided a systematic strategy to obtain a PQQ high-producing mutant strain and achieve high production of PQQ in fermentation. These practical methods could be applicable to improve the production of other antioxidant compounds with uncleared regulation mechanisms. KEY POINTS: • Improvement of PQQ production by UV-LiCl mutagenesis combined with adaptive laboratory evolution (ALE) and fermentation optimization. • A consecutive increase of oxidative stress could be used as the antagonistic factor for ALE to enhance PQQ production. • Mutations in the ftfL gene and thiC gene indicated that PQQ production might be increased by enhancing methanol consumption and cell growth.
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Affiliation(s)
- Jiale Liang
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China
| | - Mingjie Tang
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China
| | - Lang Chen
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China
| | - Wenjie Wang
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China.
| | - Xinle Liang
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018, China.
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2
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Wei Y, Yu S, Guo Q, Missen OP, Xia X. Microbial mechanisms to transform the super-trace element tellurium: a systematic review and discussion of nanoparticulate phases. World J Microbiol Biotechnol 2023; 39:262. [PMID: 37507604 PMCID: PMC10382350 DOI: 10.1007/s11274-023-03704-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023]
Abstract
Tellurium is a super-trace metalloid on Earth. Owing to its excellent physical and chemical properties, it is used in industries such as metallurgy and manufacturing, particularly of semiconductors and - more recently - solar panels. As the global demand for tellurium rises, environmental issues surrounding tellurium have recently aroused concern due to its high toxicity. The amount of tellurium released to the environment is increasing, and microorganisms play an important role in the biogeochemical cycling of environmental tellurium. This review focuses on novel developments on tellurium transformations driven by microbes and includes the following sections: (1) history and applications of tellurium; (2) toxicity of tellurium; (3) microbial detoxification mechanisms against soluble tellurium anions including uptake, efflux and methods of reduction, and reduced ability to cope with oxidation stress or repair damaged DNA; and (4) the characteristics and applications of tellurium nanoparticles (TeNPs) produced by microbes. This review raises the awareness of microorganisms in tellurium biogeochemical cycling and the growing applications for microbial tellurium nanoparticles.
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Affiliation(s)
- Yuru Wei
- Hubei Key Laboratory of Edible Wild Plants Conservation & Utilization, Hubei Engineering Research Center of Characteristic Wild Vegetable Breeding and Comprehensive Utilization Technology, Huangshi Key Laboratory of Lake Environmental Protection and Sustainable Utilization of Resources, Hubei Normal University, Huangshi, P. R. China
| | - Sihan Yu
- Hubei Key Laboratory of Edible Wild Plants Conservation & Utilization, Hubei Engineering Research Center of Characteristic Wild Vegetable Breeding and Comprehensive Utilization Technology, Huangshi Key Laboratory of Lake Environmental Protection and Sustainable Utilization of Resources, Hubei Normal University, Huangshi, P. R. China
| | - Qian Guo
- Hubei Key Laboratory of Edible Wild Plants Conservation & Utilization, Hubei Engineering Research Center of Characteristic Wild Vegetable Breeding and Comprehensive Utilization Technology, Huangshi Key Laboratory of Lake Environmental Protection and Sustainable Utilization of Resources, Hubei Normal University, Huangshi, P. R. China
| | - Owen P Missen
- Centre for Ore Deposit and Earth Sciences, University of Tasmania, TAS, Private Bag 79, Hobart, 7001, Australia.
| | - Xian Xia
- Hubei Key Laboratory of Edible Wild Plants Conservation & Utilization, Hubei Engineering Research Center of Characteristic Wild Vegetable Breeding and Comprehensive Utilization Technology, Huangshi Key Laboratory of Lake Environmental Protection and Sustainable Utilization of Resources, Hubei Normal University, Huangshi, P. R. China.
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Genomic, Molecular, and Phenotypic Characterization of Arthrobacter sp. OVS8, an Endophytic Bacterium Isolated from and Contributing to the Bioactive Compound Content of the Essential Oil of the Medicinal Plant Origanum vulgare L. Int J Mol Sci 2023; 24:ijms24054845. [PMID: 36902273 PMCID: PMC10002853 DOI: 10.3390/ijms24054845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 02/24/2023] [Accepted: 02/25/2023] [Indexed: 03/06/2023] Open
Abstract
Medicinal plants play an important role in the discovery of new bioactive compounds with antimicrobial activity, thanks to their pharmacological properties. However, members of their microbiota can also synthesize bioactive molecules. Among these, strains belonging to the genera Arthrobacter are commonly found associated with the plant's microenvironments, showing plant growth-promoting (PGP) activity and bioremediation properties. However, their role as antimicrobial secondary metabolite producers has not been fully explored. The aim of this work was to characterize the Arthrobacter sp. OVS8 endophytic strain, isolated from the medicinal plant Origanum vulgare L., from molecular and phenotypic viewpoints to evaluate its adaptation and influence on the plant internal microenvironments and its potential as a producer of antibacterial volatile molecules (VOCs). Results obtained from the phenotypic and genomic characterization highlight its ability to produce volatile antimicrobials effective against multidrug-resistant (MDR) human pathogens and its putative PGP role as a producer of siderophores and degrader of organic and inorganic pollutants. The outcomes presented in this work identify Arthrobacter sp. OVS8 as an excellent starting point toward the exploitation of bacterial endophytes as antibiotics sources.
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Mason S, Vornhagen J, Smith SN, Mike LA, Mobley HLT, Bachman MA. The Klebsiella pneumoniae ter Operon Enhances Stress Tolerance. Infect Immun 2023; 91:e0055922. [PMID: 36651775 PMCID: PMC9933665 DOI: 10.1128/iai.00559-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 12/21/2022] [Indexed: 01/19/2023] Open
Abstract
Healthcare-acquired infections are a leading cause of disease in patients that are hospitalized or in long-term-care facilities. Klebsiella pneumoniae (Kp) is a leading cause of bacteremia, pneumonia, and urinary tract infections in these settings. Previous studies have established that the ter operon, a genetic locus that confers tellurite oxide (K2TeO3) resistance, is associated with infection in colonized patients. Rather than enhancing fitness during infection, the ter operon increases Kp fitness during gut colonization; however, the biologically relevant function of this operon is unknown. First, using a murine model of urinary tract infection, we demonstrate a novel role for the ter operon protein TerC as a bladder fitness factor. To further characterize TerC, we explored a variety of functions, including resistance to metal-induced stress, resistance to radical oxygen species-induced stress, and growth on specific sugars, all of which were independent of TerC. Then, using well-defined experimental guidelines, we determined that TerC is necessary for tolerance to ofloxacin, polymyxin B, and cetylpyridinium chloride. We used an ordered transposon library constructed in a Kp strain lacking the ter operon to identify the genes that are required to resist K2TeO3-induced and polymyxin B-induced stress, which suggested that K2TeO3-induced stress is experienced at the bacterial cell envelope. Finally, we confirmed that K2TeO3 disrupts the Kp cell envelope, though these effects are independent of ter. Collectively, the results from these studies indicate a novel role for the ter operon as a stress tolerance factor, thereby explaining its role in enhancing fitness in the gut and bladder.
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Affiliation(s)
- Sophia Mason
- Department of Pathology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Jay Vornhagen
- Department of Pathology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
- Department of Microbiology & Immunology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Sara N. Smith
- Department of Microbiology & Immunology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Laura A. Mike
- Department of Medical Microbiology & Immunology, University of Toledo, Toledo, Ohio, USA
| | - Harry L. T. Mobley
- Department of Microbiology & Immunology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Michael A. Bachman
- Department of Pathology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
- Department of Microbiology & Immunology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
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Pepper-Mediated Green Synthesis of Selenium and Tellurium Nanoparticles with Antibacterial and Anticancer Potential. J Funct Biomater 2022; 14:jfb14010024. [PMID: 36662072 PMCID: PMC9867025 DOI: 10.3390/jfb14010024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/17/2022] [Accepted: 12/24/2022] [Indexed: 01/03/2023] Open
Abstract
The production of nanoparticles for biomedical applications (namely with antimicrobial and anticancer properties) has been significantly hampered using traditional physicochemical approaches, which often produce nanostructures with poor biocompatibility properties requiring post-synthesis functionalization to implement features that such biomedical applications require. As an alternative, green nanotechnology and the synthesis of environmentally friendly nanomaterials have been gaining attention over the last few decades, using living organisms or biomolecules derived from them, as the main raw materials to produce cost-effective, environmentally friendly, and ready-to-be-used nanomaterials. In this article and building upon previous knowledge, we have designed and implemented the synthesis of selenium and tellurium nanoparticles using extracts from fresh jalapeño and habanero peppers. After characterization, in this study, the nanoparticles were tested for both their antimicrobial and anticancer features against isolates of antibiotic-resistant bacterial strains and skin cancer cell lines, respectively. The nanosystems produced nanoparticles via a fast, eco-friendly, and cost-effective method showing different antimicrobial profiles between elements. While selenium nanoparticles lacked an antimicrobial effect at the concentrations tested, those made of tellurium produced a significant antibacterial effect even at the lowest concentration tested. These effects were correlated when the nanoparticles were tested for their cytocompatibility and anticancer properties. While selenium nanoparticles were biocompatible and had a dose-dependent anticancer effect, tellurium-based nanoparticles lacked such biocompatibility while exerting a powerful anti-cancer effect. Further, this study demonstrated a suitable mechanism of action for killing bacteria and cancer cells involving reactive oxygen species (ROS) generation. In summary, this study introduces a new green nanomedicine synthesis approach to create novel selenium and tellurium nanoparticles with attractive properties for numerous biomedical applications.
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Alonso‐Fernandes E, Fernández‐Llamosas H, Cano I, Serrano‐Pelejero C, Castro L, Díaz E, Carmona M. Enhancing tellurite and selenite bioconversions by overexpressing a methyltransferase from
Aromatoleum
sp. CIB. Microb Biotechnol 2022; 16:915-930. [PMID: 36366868 PMCID: PMC10128142 DOI: 10.1111/1751-7915.14162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 09/21/2022] [Accepted: 10/09/2022] [Indexed: 11/13/2022] Open
Abstract
Pollution by metalloids, e.g., tellurite and selenite, is of serious environmental concern and, therefore, there is an increasing interest in searching for ecologically friendly solutions for their elimination. Some microorganisms are able to reduce toxic tellurite/selenite into less toxic elemental tellurium (Te) and selenium (Se). Here, we describe the use of the environmentally relevant β-proteobacterium Aromatoleum sp. CIB as a platform for tellurite elimination. Aromatoleum sp. CIB was shown to tolerate 0.2 and 0.5 mM tellurite at aerobic and anaerobic conditions, respectively. Furthermore, the CIB strain was able to reduce tellurite into elemental Te producing rod-shaped Te nanoparticles (TeNPs) of around 200 nm length. A search in the genome of Aromatoleum sp. CIB revealed the presence of a gene, AzCIB_0135, which encodes a new methyltransferase that methylates tellurite and also selenite. AzCIB_0135 orthologs are widely distributed in bacterial genomes. The overexpression of the AzCIB_0135 gene both in Escherichia coli and Aromatoleum sp. CIB speeds up tellurite and selenite removal, and it enhances the production of rod-shaped TeNPs and spherical Se nanoparticles (SeNPs), respectively. Thus, the overexpression of a methylase becomes a new genetic strategy to optimize bacterial catalysts for tellurite/selenite bioremediation and for the programmed biosynthesis of metallic nanoparticles of biotechnological interest.
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Affiliation(s)
- Elena Alonso‐Fernandes
- Microbial and Plant Biotechnology Department Centro de Investigaciones Biológicas Margarita Salas‐CSIC Madrid Spain
| | - Helga Fernández‐Llamosas
- Microbial and Plant Biotechnology Department Centro de Investigaciones Biológicas Margarita Salas‐CSIC Madrid Spain
| | - Irene Cano
- Microbial and Plant Biotechnology Department Centro de Investigaciones Biológicas Margarita Salas‐CSIC Madrid Spain
| | - Cristina Serrano‐Pelejero
- Microbial and Plant Biotechnology Department Centro de Investigaciones Biológicas Margarita Salas‐CSIC Madrid Spain
| | - Laura Castro
- Department of Material Science and Metallurgical Engineering, Facultad de Químicas Universidad Complutense de Madrid Madrid Spain
| | - Eduardo Díaz
- Microbial and Plant Biotechnology Department Centro de Investigaciones Biológicas Margarita Salas‐CSIC Madrid Spain
| | - Manuel Carmona
- Microbial and Plant Biotechnology Department Centro de Investigaciones Biológicas Margarita Salas‐CSIC Madrid Spain
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7
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Tang A, Ren Q, Wu Y, Wu C, Cheng Y. Investigation into the Antibacterial Mechanism of Biogenic Tellurium Nanoparticles and Precursor Tellurite. Int J Mol Sci 2022; 23:ijms231911697. [PMID: 36232999 PMCID: PMC9569536 DOI: 10.3390/ijms231911697] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/19/2022] [Accepted: 09/26/2022] [Indexed: 11/06/2022] Open
Abstract
Antibacterial tellurium nanoparticles have the advantages of high activity and biocompatibility. Microbial synthesis of Te nanoparticles is not only a green technology but builds new ecological relationships in diverse environments. However, the antibacterial mechanism of Te nanoparticles is largely unclear. In this study, we report the bacterial synthesis of rod-shaped Te nanoparticles (BioTe) with high antibacterial activity against Escherichia coli. Morphology and permeability examination indicates that membrane damage is the primary reason for the antibacterial activity of BioTe, rather than ROS production and DNA damage. Moreover, a comparison of transcriptome and relative phenotypes reveals the difference in antibacterial mechanisms between BioTe and tellurite. Based on our evidence, we propose an antibacterial mode of rod-shaped BioTe, in which positively charged BioTe interact with the cell membrane through electrostatic attraction and then penetrate the membrane by using their sharp ends. In contrast, tellurite toxicity might be involved in sulfur metabolism.
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Affiliation(s)
- Aiguo Tang
- School of Life Sciences, Anhui University, Hefei 230601, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei 230601, China
- Anhui Key Laboratory of Modern Biomanufacturing, Hefei 230601, China
| | - Qianwen Ren
- Anhui Province Key Laboratory of Industrial Wastewater and Environmental Treatment, Hefei 230109, China
| | - Yaling Wu
- School of Life Sciences, Anhui University, Hefei 230601, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei 230601, China
- Anhui Key Laboratory of Modern Biomanufacturing, Hefei 230601, China
| | - Chao Wu
- Anhui Province Key Laboratory of Industrial Wastewater and Environmental Treatment, Hefei 230109, China
| | - Yuanyuan Cheng
- School of Life Sciences, Anhui University, Hefei 230601, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei 230601, China
- Anhui Key Laboratory of Modern Biomanufacturing, Hefei 230601, China
- Correspondence:
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Wu X, Zhan F, Zhang J, Chen S, Yang B. Identification of hypervirulent Klebsiella pneumoniae carrying terW gene by MacConkey-potassium tellurite medium in the general population. Front Public Health 2022; 10:946370. [PMID: 36091562 PMCID: PMC9448990 DOI: 10.3389/fpubh.2022.946370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 08/05/2022] [Indexed: 01/21/2023] Open
Abstract
Objectives To establish a MacConkey-potassium tellurium medium-based method for selectively culturing terW gene-positive Klebsiella pneumoniae (KP), to evaluate its performance and apply it to identifying particular clonal hypervirulent KP (hvKP) strains in epidemiological surveillance. Methods The virulence genes, rmpA, iutA, and terW, were detected by PCR. The minimum inhibitory concentration of potassium tellurite of hvKP (rmpA +/ iutA +) and classical KP (rmpA - and iutA -) was determined using the agar dilution method. The MacConkey medium containing 4 μg/ml potassium tellurite was prepared and the performance in detecting terW + KP was evaluated, including an agreement with PCR and positive/negative predictive value. Fecal samples from healthy volunteers in Fujian were collected and cultured in the medium, then positive strains were identified using MALDI-TOF MS, antimicrobial susceptibility was tested by Kirby-Bauer assays, and virulence genes and capsular serotype genes were tested by PCR. Results In KP isolated from clinical specimens (N = 198), the positive rate of terW was 37.9%, and the detection rate of terW in hvKP was significantly higher than that in classical KP (70.6% vs 13.3%). The potassium tellurite resistance levels of terW + (N = 75) and terW - (N = 55) KP were 8-128 μg/ml and <1-8 μg/ml, respectively, with significant differences. KP was selectively cultured on a MacConkey medium with 4 μg/ml potassium tellurite, and its agreement with PCR was good (Kappa=0.936), and the positive and negative percent agreement and positive and negative predictive values were 100% (75/75), 92.7% (51/55), 94.9% (75/79), and 100% (51/51), respectively. The prevalence of tellurite-resistant KP was 16.7% (86/516) in fecal samples from healthy volunteers, among which the positive rate of terW was 100% (86/86). The antimicrobial resistance characteristics of terW + KP showed no difference between healthy volunteers and inpatients. The most common capsular serotypes associated with high virulence were K1, K2, and K57. Conclusions The MacConkey medium containing 4 μg/ml potassium tellurite could easily select and culture terW + KP in fecal samples with high sensitivity and specificity, which is a practical method for the epidemic surveillance of hvKP in the general population.
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Affiliation(s)
- Xiufeng Wu
- Department of Laboratory Medicine, Fujian Medical University Union Hospital, Fuzhou, China
| | - Fuguo Zhan
- Department of Laboratory Medicine, Gene Diagnosis Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China,Fujian Key Laboratory of Laboratory Medicine, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China,First Clinical College, Fujian Medical University, Fuzhou, China
| | - Jiawei Zhang
- Department of Laboratory Medicine, Gene Diagnosis Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China,Fujian Key Laboratory of Laboratory Medicine, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China,First Clinical College, Fujian Medical University, Fuzhou, China
| | - Shanjian Chen
- Department of Laboratory Medicine, Gene Diagnosis Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China,Fujian Key Laboratory of Laboratory Medicine, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China,First Clinical College, Fujian Medical University, Fuzhou, China
| | - Bin Yang
- Department of Laboratory Medicine, Gene Diagnosis Research Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China,Fujian Key Laboratory of Laboratory Medicine, The First Affiliated Hospital, Fujian Medical University, Fuzhou, China,First Clinical College, Fujian Medical University, Fuzhou, China,*Correspondence: Bin Yang
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9
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Pham H, Tran TDT, Yang Y, Ahn JH, Hur HG, Kim YH. Analysis of phylogenetic markers for classification of a hydrogen peroxide producing Streptococcus oralis isolated from saliva by a newly devised differential medium. J Microbiol 2022; 60:795-805. [DOI: 10.1007/s12275-022-2261-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 06/22/2022] [Accepted: 06/23/2022] [Indexed: 11/30/2022]
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10
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Oxidative stress response system in Escherichia coli arising from diphenyl ditelluride (PhTe) 2 exposure. Toxicol In Vitro 2022; 83:105404. [PMID: 35654257 DOI: 10.1016/j.tiv.2022.105404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 04/25/2022] [Accepted: 05/26/2022] [Indexed: 11/20/2022]
Abstract
The toxicity of diphenyl ditelluride (PhTe)2 is associated with its ability to oxidize sulfhydryl groups from biological molecules. Therefore, we evaluated possible molecular mechanisms of toxicity induced by this organochalcogen in Escherichia coli (E. coli) by evaluating oxidative damage markers, relative expression of genes associated with the cellular redox state in bacteria, such as katG, sodA, sodB, soxS, and oxyR, as well as the activity of enzymes responsible for cellular redox balance. After exposure of (PhTe)2 (6, 12, and 24 μg/mL), there was a decrease in non-protein thiols (NPSH) levels, an increase in protein carbonylation and lipid peroxidation in E. coli. Intra- and extracellular reactive species (RS) was increased at concentrations of 6, 12, and 24 μg/mL. The superoxide dismutase (SOD) activity was increased at the three concentrations tested, while catalase (CAT) activity was higher at 12 and 24 μg/mL. The soxS gene showed lower expression at the three concentrations tested, while the oxyR gene was supressed at 24 μg/mL. The katG antioxidant response gene showed lower expression, and sodA and sodB were positively activated, except for sodB at 6 μg/mL. Our findings demonstrate that exposure to (PhTe)2 induced RS formation, NPSH depletion and changes in transcriptional factors regulation, characterizing it as a multi-target compound, causing disruption in cellular oxidative state, as well as molecular mechanisms associated in E. coli.
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11
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Naguib M, Feldman N, Zarodkiewicz P, Shropshire H, Biamis C, El-Halfawy OM, McCain J, Dezanet C, Décout JL, Chen Y, Cosa G, Valvano MA. An evolutionary conserved detoxification system for membrane lipid-derived peroxyl radicals in Gram-negative bacteria. PLoS Biol 2022; 20:e3001610. [PMID: 35580139 PMCID: PMC9113575 DOI: 10.1371/journal.pbio.3001610] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 03/18/2022] [Indexed: 11/30/2022] Open
Abstract
How double-membraned Gram-negative bacteria overcome lipid peroxidation is virtually unknown. Bactericidal antibiotics and superoxide ion stress stimulate the transcription of the Burkholderia cenocepacia bcnA gene that encodes a secreted lipocalin. bcnA gene orthologs are conserved in bacteria and generally linked to a conserved upstream gene encoding a cytochrome b561 membrane protein (herein named lcoA, lipocalin-associated cytochrome oxidase gene). Mutants in bcnA, lcoA, and in a gene encoding a conserved cytoplasmic aldehyde reductase (peroxidative stress-associated aldehyde reductase gene, psrA) display enhanced membrane lipid peroxidation. Compared to wild type, the levels of the peroxidation biomarker malondialdehyde (MDA) increase in the mutants upon exposure to sublethal concentrations of the bactericidal antibiotics polymyxin B and norfloxacin. Microscopy with lipid peroxidation-sensitive fluorescent probes shows that lipid peroxyl radicals accumulate at the bacterial cell poles and septum and peroxidation is associated with a redistribution of anionic phospholipids and reduced antimicrobial resistance in the mutants. We conclude that BcnA, LcoA, and PsrA are components of an evolutionary conserved, hitherto unrecognized peroxidation detoxification system that protects the bacterial cell envelope from lipid peroxyl radicals.
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Affiliation(s)
- Marwa Naguib
- Wellcome-Wolfson Institute for Experimental Medicine, Queen’s University Belfast, Belfast, United Kingdom
- Department of Microbiology and Immunology, Faculty of Pharmacy, Damanhour University, Damanhour, Egypt
| | - Nicolás Feldman
- Wellcome-Wolfson Institute for Experimental Medicine, Queen’s University Belfast, Belfast, United Kingdom
| | - Paulina Zarodkiewicz
- Wellcome-Wolfson Institute for Experimental Medicine, Queen’s University Belfast, Belfast, United Kingdom
| | - Holly Shropshire
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Christina Biamis
- Wellcome-Wolfson Institute for Experimental Medicine, Queen’s University Belfast, Belfast, United Kingdom
| | - Omar M. El-Halfawy
- Department of Chemistry and Biochemistry, Faculty of Science, University of Regina, Regina, Saskatchewan, Canada
- Department of Microbiology and Immunology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Julia McCain
- Department of Chemistry and Quebec Center for Advanced Materials, McGill University, Montreal, Québec, Canada
| | - Clément Dezanet
- Department of Molecular Pharmacochemistry, Université Grenoble Alpes/CNRS, Grenoble, France
| | - Jean-Luc Décout
- Department of Molecular Pharmacochemistry, Université Grenoble Alpes/CNRS, Grenoble, France
| | - Yin Chen
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Gonzalo Cosa
- Department of Chemistry and Quebec Center for Advanced Materials, McGill University, Montreal, Québec, Canada
| | - Miguel A. Valvano
- Wellcome-Wolfson Institute for Experimental Medicine, Queen’s University Belfast, Belfast, United Kingdom
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12
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Kessi J, Turner RJ, Zannoni D. Tellurite and Selenite: how can these two oxyanions be chemically different yet so similar in the way they are transformed to their metal forms by bacteria? Biol Res 2022; 55:17. [PMID: 35382884 PMCID: PMC8981825 DOI: 10.1186/s40659-022-00378-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 02/06/2022] [Indexed: 12/26/2022] Open
Abstract
This opinion review explores the microbiology of tellurite, TeO32− and selenite, SeO32− oxyanions, two similar Group 16 chalcogen elements, but with slightly different physicochemical properties that lead to intriguing biological differences. Selenium, Se, is a required trace element compared to tellurium, Te, which is not. Here, the challenges around understanding the uptake transport mechanisms of these anions, as reflected in the model organisms used by different groups, are described. This leads to a discussion around how these oxyanions are subsequently reduced to nanomaterials, which mechanistically, has controversies between ideas around the molecule chemistry, chemical reactions involving reduced glutathione and reactive oxygen species (ROS) production along with the bioenergetics at the membrane versus the cytoplasm. Of particular interest is the linkage of glutathione and thioredoxin chemistry from the cytoplasm through the membrane electron transport chain (ETC) system/quinones to the periplasm. Throughout the opinion review we identify open and unanswered questions about the microbial physiology under selenite and tellurite exposure. Thus, demonstrating how far we have come, yet the exciting research directions that are still possible. The review is written in a conversational manner from three long-term researchers in the field, through which to play homage to the late Professor Claudio Vásquez.
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Affiliation(s)
- Janine Kessi
- Until 2018 - Dept of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Raymond J Turner
- Dept of Biological Sciences, University of Calgary, Calgary, AB, Canada.
| | - Davide Zannoni
- Dept of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
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Muñoz-Diaz P, Jiménez K, Luraschi R, Cornejo F, Figueroa M, Vera C, Rivas-Pardo A, Sandoval JM, Vásquez C, Arenas F. Anaerobic RSH-dependent tellurite reduction contributes to Escherichia coli tolerance against tellurite. Biol Res 2022; 55:13. [PMID: 35313991 PMCID: PMC8935827 DOI: 10.1186/s40659-022-00383-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 03/07/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Tellurium is a rare metalloid that exerts high toxicity on cells, especially on bacteria, partly due to reactive oxygen species (ROS) generation. Moreover, it has also been observed that tellurite can target free cell thiols groups (RSH) (i.e. reduced glutathione (GSH)), enhancing the cellular redox imbalance. Additionally, in vitro experiments have suggested that several enzymes can reduce tellurite (IV) to its elemental form (0); where RSH present on their active sites may be responsible for the process. Nevertheless, the mechanisms implemented by bacteria for tellurite reduction and its role in resistance have not been evaluated in vivo. RESULTS This work shows that tellurite reduction to elemental tellurium is increased under anaerobic conditions in E. coli cells. The in vivo tellurite reduction is related to the intracellular concentration of total RSH, in the presence and absence of oxygen. This metabolization of tellurite directly contributes to the resistance of the bacteria to the oxyanion. CONCLUSIONS We demonstrated that in vivo tellurite reduction is related to the intracellular thiol concentration, i.e. large availability of cellular RSH groups, results in a more significant reduction of tellurite. Furthermore, we observed that, when the bacterium exhibits less resistance to the oxyanion, a decreased tellurite reduction was seen, affecting the growth fitness. Together, these results let us propose that tellurite reduction and the intracellular RSH content are related to the oxyanion bacterial resistance, this tripartite mechanism in an oxygen-independent anaerobic process.
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Affiliation(s)
- P Muñoz-Diaz
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química Y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - K Jiménez
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química Y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - R Luraschi
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química Y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - F Cornejo
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química Y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - M Figueroa
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química Y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - C Vera
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química Y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - A Rivas-Pardo
- Laboratorio de Genómica Microbiana, Centro de Genómica Y Bioinformática, Universidad Mayor, Santiago, Chile
| | - J M Sandoval
- Facultad de Ciencias, Universidad Arturo Prat, Iquique, Chile
| | - C Vásquez
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química Y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - F Arenas
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química Y Biología, Universidad de Santiago de Chile, Santiago, Chile.
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Pleiotropic actions of phenothiazine drugs are detrimental to Gram-negative bacterial persister cells. Commun Biol 2022; 5:217. [PMID: 35264714 PMCID: PMC8907348 DOI: 10.1038/s42003-022-03172-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 02/15/2022] [Indexed: 12/28/2022] Open
Abstract
Bacterial persister cells are temporarily tolerant to bactericidal antibiotics but are not necessarily dormant and may exhibit physiological activities leading to cell damage. Based on the link between fluoroquinolone-mediated SOS responses and persister cell recovery, we screened chemicals that target fluoroquinolone persisters. Metabolic inhibitors (e.g., phenothiazines) combined with ofloxacin (OFX) perturbed persister levels in metabolically active cell populations. When metabolically stimulated, intrinsically tolerant stationary phase cells also became OFX-sensitive in the presence of phenothiazines. The effects of phenothiazines on cell metabolism and physiology are highly pleiotropic: at sublethal concentrations, phenothiazines reduce cellular metabolic, transcriptional, and translational activities; impair cell repair and recovery mechanisms; transiently perturb membrane integrity; and disrupt proton motive force by dissipating the proton concentration gradient across the cell membrane. Screening a subset of mutant strains lacking membrane-bound proteins revealed the pleiotropic effects of phenothiazines potentially rely on their ability to inhibit a wide range of critical metabolic proteins. Altogether, our study further highlights the complex roles of metabolism in persister cell formation, survival and recovery, and suggests metabolic inhibitors such as phenothiazines can be selectively detrimental to persister cells.
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15
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Peng W, Wang Y, Fu Y, Deng Z, Lin S, Liang R. Characterization of the Tellurite-Resistance Properties and Identification of the Core Function Genes for Tellurite Resistance in Pseudomonas citronellolis SJTE-3. Microorganisms 2022; 10:microorganisms10010095. [PMID: 35056544 PMCID: PMC8779313 DOI: 10.3390/microorganisms10010095] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 12/27/2021] [Accepted: 12/30/2021] [Indexed: 11/16/2022] Open
Abstract
Tellurite is highly toxic to bacteria and commonly used in the clinical screening for pathogens; it is speculated that there is a potential relationship between tellurite resistance and bacterial pathogenicity. Until now, the core function genes of tellurite resistance and their characteristics are still obscure. Pseudomonas citronellolis SJTE-3 was found able to resist high concentrations of tellurite (250 μg/mL) and formed vacuole-like tellurium nanostructures. The terZABCDE gene cluster located in the large plasmid pRBL16 endowed strain SJTE-3 with the tellurite resistance of high levels. Although the terC and terD genes were identified as the core function genes for tellurite reduction and resistance, the inhibition of cell growth was observed when they were used solely. Interestingly, co-expression of the terA gene or terZ gene could relieve the burden caused by the expression of the terCD genes and recover normal cell growth. TerC and TerD proteins commonly shared the conserved sequences and are widely distributed in many pathogenic bacteria, highly associated with the pathogenicity factors.
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Affiliation(s)
- Wanli Peng
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; (W.P.); (Y.W.); (Y.F.); (Z.D.); (S.L.)
- Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yanqiu Wang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; (W.P.); (Y.W.); (Y.F.); (Z.D.); (S.L.)
- Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yali Fu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; (W.P.); (Y.W.); (Y.F.); (Z.D.); (S.L.)
- Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zixin Deng
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; (W.P.); (Y.W.); (Y.F.); (Z.D.); (S.L.)
- Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Shuangjun Lin
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; (W.P.); (Y.W.); (Y.F.); (Z.D.); (S.L.)
- Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Rubing Liang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; (W.P.); (Y.W.); (Y.F.); (Z.D.); (S.L.)
- Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
- Correspondence: ; Tel./Fax: +86-21-34204192
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Kuhl T, Chowdhury SP, Uhl J, Rothballer M. Genome-Based Characterization of Plant-Associated Rhodococcus qingshengii RL1 Reveals Stress Tolerance and Plant-Microbe Interaction Traits. Front Microbiol 2021; 12:708605. [PMID: 34489897 PMCID: PMC8416521 DOI: 10.3389/fmicb.2021.708605] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/26/2021] [Indexed: 11/24/2022] Open
Abstract
Stress tolerant, plant-associated bacteria can play an important role in maintaining a functional plant microbiome and protecting plants against various (a)biotic stresses. Members of the stress tolerant genus Rhodococcus are frequently found in the plant microbiome. Rhodococcus qingshengii RL1 was isolated from Eruca sativa and the complete genome was sequenced, annotated and analyzed using different bioinformatic tools. A special focus was laid on functional analyses of stress tolerance and interactions with plants. The genome annotation of RL1 indicated that it contains a repertoire of genes which could enable it to survive under different abiotic stress conditions for e.g., elevated mercury concentrations, to interact with plants via root colonization, to produce phytohormones and siderophores, to fix nitrogen and to interact with bacterial signaling via a LuxR-solo and quorum quenching. Based on the identified genes, functional analyses were performed in vitro with RL1 under different growth conditions. The R. qingshengii type strain djl6 and a closely related Rhodococcus erythropolis BG43 were included in the experiments to find common and distinct traits between the strains. Genome based phylogenetic analysis of 15 available and complete R. erythropolis and R. qingshengii genome sequences revealed a separation of the R. erythropolis clade in two subgroups. First one harbors only R. erythropolis strains including the R. erythropolis type strain. The second group consisted of the R. qingshengii type strain and a mix of R. qingshengii and R. erythropolis strains indicating that some strains of the second group should be considered for taxonomic re-assignment. However, BG43 was clearly identified as R. erythropolis and RL1 clearly as R. qingshengii and the strains had most tested traits in common, indicating a close functional overlap of traits between the two species.
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Affiliation(s)
- Theresa Kuhl
- Institute for Network Biology, Helmholtz Zentrum München – German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Soumitra Paul Chowdhury
- Institute for Network Biology, Helmholtz Zentrum München – German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Jenny Uhl
- Research Unit Analytical Biogeochemistry, Helmholtz Zentrum München – German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Michael Rothballer
- Institute for Network Biology, Helmholtz Zentrum München – German Research Center for Environmental Health (GmbH), Neuherberg, Germany
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Goff JL, Wang Y, Boyanov MI, Yu Q, Kemner KM, Fein JB, Yee N. Tellurite Adsorption onto Bacterial Surfaces. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:10378-10386. [PMID: 34279081 DOI: 10.1021/acs.est.1c01001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Tellurium (Te) is an emerging contaminant and its chemical transformation in the environment is strongly influenced by microbial processes. In this study, we investigated the adsorption of tellurite [Te(IV), TeO32-] onto the common soil bacterium Bacillus subtilis. Thiol-blocking experiments were carried out to investigate the role of cell surface sulfhydryl sites in tellurite binding, and extended X-ray absorption fine structure (EXAFS) spectroscopy was performed to determine the chemical speciation of the adsorbed tellurite. The results indicate that tellurite reacts with sulfhydryl functional groups in the extracellular polymeric substances (EPS) produced by B. subtilis. Upon binding to sulfhydryl sites in the EPS, the Te changes from Te-O bonds to Te-S coordination. Further analysis of the surface-associated molecules shows that the EPS of B. subtilis contain proteins. Removal of the proteinaceous EPS dramatically decreases tellurite adsorption and the sulfhydryl surface site concentration. These findings indicate that sulfhydryl binding in EPS plays a key role in tellurite adsorption on bacterial surfaces.
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Affiliation(s)
- Jennifer L Goff
- Department of Earth and Planetary Sciences, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Yuwei Wang
- Department of Environmental Sciences, Rutgers University, New Brunswick, New Jersey 08901, United States
| | - Maxim I Boyanov
- Bulgarian Academy of Sciences, Institute of Chemical Engineering, Sofia 1113, Bulgaria
- Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Qiang Yu
- Department of Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Kenneth M Kemner
- Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Jeremy B Fein
- Department of Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Nathan Yee
- Department of Earth and Planetary Sciences, Rutgers University, Piscataway, New Jersey 08854, United States
- Department of Environmental Sciences, Rutgers University, New Brunswick, New Jersey 08901, United States
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18
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Goff JL, Boyanov MI, Kemner KM, Yee N. The role of cysteine in tellurate reduction and toxicity. Biometals 2021; 34:937-946. [PMID: 34255250 DOI: 10.1007/s10534-021-00319-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 05/13/2021] [Indexed: 11/29/2022]
Abstract
The tellurium oxyanion tellurate is toxic to living organisms even at low concentrations; however, its mechanism of toxicity is poorly understood. Here, we show that exposure of Escherichia coli K-12 to tellurate results in reduction to elemental tellurium (Te[0]) and the formation of intracellular reactive oxygen species (ROS). Toxicity assays performed with E. coli indicated that pre-oxidation of the intracellular thiol pools increases cellular resistance to tellurate-suggesting that intracellular thiols are important in tellurate toxicity. X-ray absorption spectroscopy experiments demonstrated that cysteine reduces tellurate to elemental tellurium. This redox reaction was found to generate superoxide anions. These results indicate that tellurate reduction to Te(0) by cysteine is a source of ROS in the cytoplasm of tellurate-exposed cells.
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Affiliation(s)
- Jennifer L Goff
- Department of Earth and Planetary Sciences, Rutgers University, Piscataway, NJ, 08854, USA.
| | - Maxim I Boyanov
- Bulgarian Academy of Sciences, Institute of Chemical Engineering, 1113, Sofia, Bulgaria.,Biosciences Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Kenneth M Kemner
- Biosciences Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Nathan Yee
- Department of Earth and Planetary Sciences, Rutgers University, Piscataway, NJ, 08854, USA.,Department of Environmental Sciences, Rutgers University, New Brunswick, NJ, 08901, USA
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19
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Nguyen TTH, Kikuchi T, Tokunaga T, Iyoda S, Iguchi A. Diversity of the Tellurite Resistance Gene Operon in Escherichia coli. Front Microbiol 2021; 12:681175. [PMID: 34122392 PMCID: PMC8193136 DOI: 10.3389/fmicb.2021.681175] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 04/30/2021] [Indexed: 11/15/2022] Open
Abstract
Tellurite is highly toxic to most bacteria owing to its strong oxidative ability. However, some bacteria demonstrate tellurite resistance. In particular, some Escherichia coli strains, including Shiga toxin-producing E. coli O157:H7, are known to be resistant to tellurite. This resistance is involved in ter operon, which is usually located on a prophage-like element of the chromosome. The characteristics of the ter operon have been investigated mainly by genome analysis of pathogenic E. coli; however, the distribution and structural characteristics of the ter operon in other E. coli are almost unknown. To clarify these points, we examined 106 E. coli strains carrying the ter operon from various animals. The draft genomes of 34 representative strains revealed that ter operons were clearly classified into four subtypes, ter-type 1–4, at the nucleotide sequence level. Complete genomic sequences revealed that operons belonging to three ter-types (1, 3, and 4) were located on the prophage-like elements on the chromosome, whereas the ter-type 2 operon was located on the IncHI2 plasmid. The positions of the tRNASer, tRNAMet, and tRNAPhe indicated the insertion sites of elements carrying the ter operons. Using the PCR method developed in this study, 106 strains were classified as type 1 (n = 66), 2 (n = 13), 3 (n = 8), and 4 (n = 17), and two strains carried both types 1 and 2. Furthermore, significant differences in the minimum inhibitory concentration (MIC) of tellurite were observed between strains carrying ter-type 4 and the others (p < 0.05). The ter-type was also closely related to the isolation source, with types 2 and 4 associated with chickens and deer, respectively. This study provided new insights related not only to genetic characteristics of the ter operons, but also to phenotypic and ecological characteristics that may be related to the diversity of the operon.
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Affiliation(s)
- Thi Thu Huong Nguyen
- Department of Environment and Resource Sciences, University of Miyazaki, Miyazaki, Japan.,Thai Nguyen University of Agriculture and Forestry, Thai Nguyen, Vietnam
| | - Taisei Kikuchi
- Department of Infectious Disease, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Tadaaki Tokunaga
- Department of Environment and Resource Sciences, University of Miyazaki, Miyazaki, Japan
| | - Sunao Iyoda
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Atsushi Iguchi
- Department of Environment and Resource Sciences, University of Miyazaki, Miyazaki, Japan
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20
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Bessaiah H, Pokharel P, Loucif H, Kulbay M, Sasseville C, Habouria H, Houle S, Bernier J, Massé É, Van Grevenynghe J, Dozois CM. The RyfA small RNA regulates oxidative and osmotic stress responses and virulence in uropathogenic Escherichia coli. PLoS Pathog 2021; 17:e1009617. [PMID: 34043736 PMCID: PMC8205139 DOI: 10.1371/journal.ppat.1009617] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 06/15/2021] [Accepted: 05/05/2021] [Indexed: 12/17/2022] Open
Abstract
Urinary tract infections (UTIs) are a common bacterial infectious disease in humans, and strains of uropathogenic Escherichia coli (UPEC) are the most frequent cause of UTIs. During infection, UPEC must cope with a variety of stressful conditions in the urinary tract. Here, we demonstrate that the small RNA (sRNA) RyfA of UPEC strains is required for resistance to oxidative and osmotic stresses. Transcriptomic analysis of the ryfA mutant showed changes in expression of genes associated with general stress responses, metabolism, biofilm formation and genes coding for cell surface proteins. Inactivation of ryfA in UPEC strain CFT073 decreased urinary tract colonization in mice and the ryfA mutant also had reduced production of type 1 and P fimbriae (pili), adhesins which are known to be important for UTI. Furthermore, loss of ryfA also reduced UPEC survival in human macrophages. Thus, ryfA plays a key regulatory role in UPEC adaptation to stress, which contributes to UTI and survival in macrophages.
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Affiliation(s)
- Hicham Bessaiah
- INRS-Centre Armand-Frappier Santé Biotechnologie, Laval, Québec, Canada
- CRIPA-Centre de recherche en infectiologie porcine et avicole, Saint-Hyacinthe, Québec, Canada
| | - Pravil Pokharel
- INRS-Centre Armand-Frappier Santé Biotechnologie, Laval, Québec, Canada
- CRIPA-Centre de recherche en infectiologie porcine et avicole, Saint-Hyacinthe, Québec, Canada
| | - Hamza Loucif
- INRS-Centre Armand-Frappier Santé Biotechnologie, Laval, Québec, Canada
| | - Merve Kulbay
- INRS-Centre Armand-Frappier Santé Biotechnologie, Laval, Québec, Canada
| | - Charles Sasseville
- Department of Biochemistry, RNA Group, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Hajer Habouria
- INRS-Centre Armand-Frappier Santé Biotechnologie, Laval, Québec, Canada
- CRIPA-Centre de recherche en infectiologie porcine et avicole, Saint-Hyacinthe, Québec, Canada
| | - Sébastien Houle
- INRS-Centre Armand-Frappier Santé Biotechnologie, Laval, Québec, Canada
- CRIPA-Centre de recherche en infectiologie porcine et avicole, Saint-Hyacinthe, Québec, Canada
| | - Jacques Bernier
- INRS-Centre Armand-Frappier Santé Biotechnologie, Laval, Québec, Canada
| | - Éric Massé
- Department of Biochemistry, RNA Group, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | | | - Charles M. Dozois
- INRS-Centre Armand-Frappier Santé Biotechnologie, Laval, Québec, Canada
- CRIPA-Centre de recherche en infectiologie porcine et avicole, Saint-Hyacinthe, Québec, Canada
- * E-mail:
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21
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Maertens L, Cherry P, Tilquin F, Van Houdt R, Matroule JY. Environmental Conditions Modulate the Transcriptomic Response of Both Caulobacter crescentus Morphotypes to Cu Stress. Microorganisms 2021; 9:1116. [PMID: 34064119 PMCID: PMC8224329 DOI: 10.3390/microorganisms9061116] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 05/18/2021] [Accepted: 05/19/2021] [Indexed: 12/13/2022] Open
Abstract
Bacteria encounter elevated copper (Cu) concentrations in multiple environments, varying from mining wastes to antimicrobial applications of copper. As the role of the environment in the bacterial response to Cu ion exposure remains elusive, we used a tagRNA-seq approach to elucidate the disparate responses of two morphotypes of Caulobacter crescentus NA1000 to moderate Cu stress in a complex rich (PYE) medium and a defined poor (M2G) medium. The transcriptome was more responsive in M2G, where we observed an extensive oxidative stress response and reconfiguration of the proteome, as well as the induction of metal resistance clusters. In PYE, little evidence was found for an oxidative stress response, but several transport systems were differentially expressed, and an increased need for histidine was apparent. These results show that the Cu stress response is strongly dependent on the cellular environment. In addition, induction of the extracytoplasmic function sigma factor SigF and its regulon was shared by the Cu stress responses in both media, and its central role was confirmed by the phenotypic screening of a sigF::Tn5 mutant. In both media, stalked cells were more responsive to Cu stress than swarmer cells, and a stronger basal expression of several cell protection systems was noted, indicating that the swarmer cell is inherently more Cu resistant. Our approach also allowed for detecting several new transcription start sites, putatively indicating small regulatory RNAs, and additional levels of Cu-responsive regulation.
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Affiliation(s)
- Laurens Maertens
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre (SCK CEN), 2400 Mol, Belgium; (L.M.); (R.V.H.)
- Research Unit in Microorganisms Biology (URBM), Narilis Institute, University of Namur, 5000 Namur, Belgium; (P.C.); (F.T.)
| | - Pauline Cherry
- Research Unit in Microorganisms Biology (URBM), Narilis Institute, University of Namur, 5000 Namur, Belgium; (P.C.); (F.T.)
| | - Françoise Tilquin
- Research Unit in Microorganisms Biology (URBM), Narilis Institute, University of Namur, 5000 Namur, Belgium; (P.C.); (F.T.)
| | - Rob Van Houdt
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre (SCK CEN), 2400 Mol, Belgium; (L.M.); (R.V.H.)
| | - Jean-Yves Matroule
- Research Unit in Microorganisms Biology (URBM), Narilis Institute, University of Namur, 5000 Namur, Belgium; (P.C.); (F.T.)
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22
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Morena AG, Bassegoda A, Hoyo J, Tzanov T. Hybrid Tellurium-Lignin Nanoparticles with Enhanced Antibacterial Properties. ACS APPLIED MATERIALS & INTERFACES 2021; 13:14885-14893. [PMID: 33754695 PMCID: PMC8480780 DOI: 10.1021/acsami.0c22301] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The surge of antibiotic-resistant bacteria is leading to the loss of effectiveness of antibiotic treatment, resulting in prolonged infections and even death. Against this healthcare threat, antimicrobial nanoparticles that hamper the evolution of resistance mechanisms are promising alternatives to antibiotics. Herein, we used Kraft lignin, a poorly valorized polymer derived from plant biomass, to develop novel hybrid tellurium-lignin nanoparticles (TeLigNPs) as alternative antimicrobial agents. The sonochemically synthesized TeLigNPs are comprised of a lignin matrix with embedded Te clusters, revealing the role of lignin as both a reducing agent and a structural component. The hybrid NPs showed strong bactericidal effects against the Gram-negative Escherichia coli and Pseudomonas aeruginosa, achieving more than 5 log bacteria reduction, while they only slightly inhibited the growth of the Gram-positive Staphylococcus aureus. Exposure of TeLigNPs to human cells did not cause morphological changes or reduction in cell viability. Studies on the antimicrobial mechanism of action demonstrated that the novel TeLigNPs were able to disturb bacterial model membranes and generate reactive oxygen species (ROS) in Gram-negative bacteria.
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Vornhagen J, Bassis CM, Ramakrishnan S, Hein R, Mason S, Bergman Y, Sunshine N, Fan Y, Holmes CL, Timp W, Schatz MC, Young VB, Simner PJ, Bachman MA. A plasmid locus associated with Klebsiella clinical infections encodes a microbiome-dependent gut fitness factor. PLoS Pathog 2021; 17:e1009537. [PMID: 33930099 PMCID: PMC8115787 DOI: 10.1371/journal.ppat.1009537] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 05/12/2021] [Accepted: 04/07/2021] [Indexed: 02/07/2023] Open
Abstract
Klebsiella pneumoniae (Kp) is an important cause of healthcare-associated infections, which increases patient morbidity, mortality, and hospitalization costs. Gut colonization by Kp is consistently associated with subsequent Kp disease, and patients are predominantly infected with their colonizing strain. Our previous comparative genomics study, between disease-causing and asymptomatically colonizing Kp isolates, identified a plasmid-encoded tellurite (TeO3-2)-resistance (ter) operon as strongly associated with infection. However, TeO3-2 is extremely rare and toxic to humans. Thus, we used a multidisciplinary approach to determine the biological link between ter and Kp infection. First, we used a genomic and bioinformatic approach to extensively characterize Kp plasmids encoding the ter locus. These plasmids displayed substantial variation in plasmid incompatibility type and gene content. Moreover, the ter operon was genetically independent of other plasmid-encoded virulence and antibiotic resistance loci, both in our original patient cohort and in a large set (n = 88) of publicly available ter operon-encoding Kp plasmids, indicating that the ter operon is likely playing a direct, but yet undescribed role in Kp disease. Next, we employed multiple mouse models of infection and colonization to show that 1) the ter operon is dispensable during bacteremia, 2) the ter operon enhances fitness in the gut, 3) this phenotype is dependent on the colony of origin of mice, and 4) antibiotic disruption of the gut microbiota eliminates the requirement for ter. Furthermore, using 16S rRNA gene sequencing, we show that the ter operon enhances Kp fitness in the gut in the presence of specific indigenous microbiota, including those predicted to produce short chain fatty acids. Finally, administration of exogenous short-chain fatty acids in our mouse model of colonization was sufficient to reduce fitness of a ter mutant. These findings indicate that the ter operon, strongly associated with human infection, encodes factors that resist stress induced by the indigenous gut microbiota during colonization. This work represents a substantial advancement in our molecular understanding of Kp pathogenesis and gut colonization, directly relevant to Kp disease in healthcare settings.
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Affiliation(s)
- Jay Vornhagen
- Department of Pathology, University of Michigan, Ann Arbor, MI, United States of America
- Department of Microbiology & Immunology, University of Michigan, Ann Arbor, MI, United States of America
| | - Christine M. Bassis
- Department of Internal Medicine/Infectious Diseases Division, University of Michigan, Ann Arbor, MI, United States of America
| | - Srividya Ramakrishnan
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, United States of America
| | - Robert Hein
- Department of Internal Medicine/Infectious Diseases Division, University of Michigan, Ann Arbor, MI, United States of America
| | - Sophia Mason
- Department of Pathology, University of Michigan, Ann Arbor, MI, United States of America
| | - Yehudit Bergman
- Division of Medical Microbiology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Nicole Sunshine
- Department of Pathology, University of Michigan, Ann Arbor, MI, United States of America
| | - Yunfan Fan
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
| | - Caitlyn L. Holmes
- Department of Pathology, University of Michigan, Ann Arbor, MI, United States of America
- Department of Microbiology & Immunology, University of Michigan, Ann Arbor, MI, United States of America
| | - Winston Timp
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States of America
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
- Department of Medicine, Division of Infectious Disease, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Michael C. Schatz
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, United States of America
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States of America
- Simons Center for Quantitative Biology, Cold Spring Harbor, NY, United States of America
| | - Vincent B. Young
- Department of Microbiology & Immunology, University of Michigan, Ann Arbor, MI, United States of America
- Department of Internal Medicine/Infectious Diseases Division, University of Michigan, Ann Arbor, MI, United States of America
| | - Patricia J. Simner
- Division of Medical Microbiology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Michael A. Bachman
- Department of Pathology, University of Michigan, Ann Arbor, MI, United States of America
- Department of Microbiology & Immunology, University of Michigan, Ann Arbor, MI, United States of America
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Montenegro R, Vieto S, Wicki-Emmenegger D, Vásquez-Castro F, Coronado-Ruiz C, Fuentes-Schweizer P, Calderón P, Pereira R, Chavarría M. The putative phosphate transporter PitB (PP1373) is involved in tellurite uptake in Pseudomonas putida KT2440. Microbiology (Reading) 2021; 167. [DOI: 10.1099/mic.0.001002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Tellurium oxyanions are chemical species of great toxicity and their presence in the environment has increased because of mining industries and photovoltaic and electronic waste. Recovery strategies for this metalloid that are based on micro-organisms are of interest, but further studies of the transport systems and enzymes responsible for implementing tellurium transformations are required because many mechanisms remain unknown. Here, we investigated the involvement in tellurite uptake of the putative phosphate transporter PitB (PP1373) in soil bacterium
Pseudomonas putida
KT2440. For this purpose, through a method based on the CRISPR/Cas9 system, we generated a strain deficient in the pitB gene and characterized its phenotype on exposing it to varied concentrations of tellurite. Growth curves and transmission electronic microscopy experiments for the wild-type and ΔpitB strains showed that both were able to internalize tellurite into the cytoplasm and reduce the oxyanion to black nano-sized and rod-shaped tellurium particles, although the ΔpitB strain showed an increased resistance to the tellurite toxic effects. At a concentration of 100 μM tellurite, where the biomass formation of the wild-type strain decreased by half, we observed a greater ability of ΔpitB to reduce this oxyanion with respect to the wild-type strain (~38 vs ~16 %), which is related to the greater biomass production of ΔpitB and not to a greater consumption of tellurite per cell. The phenotype of the mutant was restored on over-expressing pitB in trans. In summary, our results indicate that PitB is one of several transporters responsible for tellurite uptake in
P. putida
KT2440.
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Affiliation(s)
- Rafael Montenegro
- Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, 1174-1200 San José, Costa Rica
| | - Sofía Vieto
- Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, 1174-1200 San José, Costa Rica
| | - Daniela Wicki-Emmenegger
- Escuela de Química, Universidad de Costa Rica, 11501-2060 San José, Costa Rica
- Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, 1174-1200 San José, Costa Rica
- Centro de Investigaciones en Productos Naturales (CIPRONA), Universidad de Costa Rica, 11501-2060 San José, Costa Rica
| | - Felipe Vásquez-Castro
- Escuela de Química, Universidad de Costa Rica, 11501-2060 San José, Costa Rica
- Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, 1174-1200 San José, Costa Rica
| | - Carolina Coronado-Ruiz
- Escuela de Química, Universidad de Costa Rica, 11501-2060 San José, Costa Rica
- Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, 1174-1200 San José, Costa Rica
| | - Paola Fuentes-Schweizer
- Centro de Electroquímica y Energía Química (CELEQ), Universidad de Costa Rica, 11501-2060 San José, Costa Rica
- Escuela de Química, Universidad de Costa Rica, 11501-2060 San José, Costa Rica
| | - Paula Calderón
- Centro de Investigaciones en Estructuras Microscópicas (CIEMIC), Universidad de Costa Rica, 11501-2060 San José, Costa Rica
| | - Reinaldo Pereira
- Laboratorio Nacional de Nanotecnología (LANOTEC), CeNAT-CONARE, 1174-1200 San José, Costa Rica
| | - Max Chavarría
- Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, 1174-1200 San José, Costa Rica
- Centro de Investigaciones en Productos Naturales (CIPRONA), Universidad de Costa Rica, 11501-2060 San José, Costa Rica
- Escuela de Química, Universidad de Costa Rica, 11501-2060 San José, Costa Rica
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25
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de Souza Valente C, Wan AHL. Vibrio and major commercially important vibriosis diseases in decapod crustaceans. J Invertebr Pathol 2021; 181:107527. [PMID: 33406397 DOI: 10.1016/j.jip.2020.107527] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 12/25/2020] [Accepted: 12/28/2020] [Indexed: 12/18/2022]
Abstract
Bacteria fromthe Vibriogenus are autochthonous to aquatic environments and ubiquitous in aquaculture production systems. Many Vibrio species are non-pathogenic and can be commonly found in healthy farmed aquatic animals. However, some Vibrio species and strains are pathogenic leading to a variety of 'vibriosis' diseases. These diseases can have a significant negative impact on animal production, including farmed crustaceans such as shrimps, lobsters, and crabs. As such, vibriosis can pose a threat to meeting growing food demand and global food security. Preventive management is essential to avoid the onset of vibriosis. This includes a robust health management plan, the use of prophylaxis and treatment measures, and enhancing animal health through nutrition. Furthermore, the use of probiotics, prebiotics, synbiotics, quorum sensing disruption, green water, biofloc, bacteriophages, and immune priming could also play a role in preventing and controlling a vibriosis outbreak. This review aims to inform and update the reader about the current state of knowledge about Vibrio and associated vibriosis in farmed crustaceans (i.e. shrimp, lobster, and crabs). Furthermore, the review will identify potential knowledge gaps in the literature, which serves as a basis for future research priorities.
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Affiliation(s)
- Cecília de Souza Valente
- Aquaculture and Nutrition Research Unit, Room 204, Annex Building, Ryan Institute and School of Natural Sciences, National University of Ireland Galway, Galway City H91 TK33, Ireland; Aquaculture and Nutrition Research Unit, Carna Research Station, Ryan Institute, National University of Ireland Galway, Carna, Connemara, Co. Galway H91 V8Y1, Ireland.
| | - Alex H L Wan
- Aquaculture and Nutrition Research Unit, Room 204, Annex Building, Ryan Institute and School of Natural Sciences, National University of Ireland Galway, Galway City H91 TK33, Ireland; Aquaculture and Nutrition Research Unit, Carna Research Station, Ryan Institute, National University of Ireland Galway, Carna, Connemara, Co. Galway H91 V8Y1, Ireland
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Oetiker N, Muñoz-Villagrán C, Vásquez CC, Bravo D, Pérez-Donoso JM. Bacterial phototoxicity of biomimetic CdTe-GSH quantum dots. J Appl Microbiol 2020; 131:155-168. [PMID: 33274558 DOI: 10.1111/jam.14957] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 11/12/2020] [Accepted: 11/29/2020] [Indexed: 12/12/2022]
Abstract
AIM Fluorescent semiconductor nanoparticles or quantum dots (QDs) have excellent properties as photosensitizers in photodynamic therapy. This is mainly a consequence of their nanometric size and the generation of light-activated redox species. In previous works, we have reported the low-cost biomimetic synthesis of glutathione (GSH) capped QDs (CdTe-GSH QDs) with high biocompatibility. However, no studies have been performed to determine their phototoxic effect. The aim of this work was to characterize the light-induced toxicity of green (QDs500 ) and red (QDs600 ) QDs in Escherichia coli, and to study the molecular mechanism involved. METHODS AND RESULTS Photodegradation and reduction power of biomimetic QDs was determined to analyse their potential for radical generation. Escherichia coli cells were exposed to photoactivated QDs and viability was evaluated at different times. High toxicity was determined in E. coli cells exposed to photoactivated QDs, particularly QDs500 . The molecular mechanism involved in QDs phototoxicity was studied by determining Cd2+ -release and intracellular reactive oxygen species (ROS). Cells exposed to photoactivated QDs500 presented high levels of ROS. Cells exposed to photoactivated QDs500 presented high levels of ROS. Finally, to understand this phenomenon and the importance of oxidative and cadmium-stress in QDs-mediated phototoxicity, experiments were performed in E. coli mutants in ROS and Cd2+ response genes. As expected, E. coli mutants in ROS response genes were more sensitive than the wt strain to photoactivated QDs, with a higher effect in green-QDs500 . No increase in phototoxicity was observed in cadmium-related mutants. CONCLUSION Obtained results indicate that light exposure increases the toxicity of biomimetic QDs on E. coli cells. The mechanism of bacterial phototoxicity of biomimetic CdTe-GSH QDs is mostly associated with ROS generation. SIGNIFICANCE AND IMPACT OF THE STUDY The results presented establish biomimetic CdTe-GSH QDs as a promising cost-effective alternative against microbial infections, particularly QDs500 .
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Affiliation(s)
- N Oetiker
- BioNanotechnology and Microbiology Laboratory, Center of Bioinformatics and Integrative Biology (CBIB), Biological Sciences Faculty, Universidad Andres Bello, Santiago, Chile
| | - C Muñoz-Villagrán
- Molecular Microbiology Laboratory, Chemistry and Biology Faculty, Universidad de Santiago de Chile, Santiago, Chile
| | - C C Vásquez
- Molecular Microbiology Laboratory, Chemistry and Biology Faculty, Universidad de Santiago de Chile, Santiago, Chile
| | - D Bravo
- Oral Microbiology Laboratory, Dentistry Faculty, Universidad de Chile, Santiago, Chile
| | - J M Pérez-Donoso
- BioNanotechnology and Microbiology Laboratory, Center of Bioinformatics and Integrative Biology (CBIB), Biological Sciences Faculty, Universidad Andres Bello, Santiago, Chile
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27
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Park S, Nam EW, Kim Y, Lee S, Kim SI, Yoon H. Transcriptomic Approach for Understanding the Adaptation of Salmonella enterica to Contaminated Produce. J Microbiol Biotechnol 2020; 30:1729-1738. [PMID: 32830190 PMCID: PMC9728351 DOI: 10.4014/jmb.2007.07036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 08/15/2020] [Accepted: 08/19/2020] [Indexed: 12/15/2022]
Abstract
Salmonellosis is a form of gastroenteritis caused by Salmonella infection. The main transmission route of salmonellosis has been identified as poorly cooked meat and poultry products contaminated with Salmonella. However, in recent years, the number of outbreaks attributed to contaminated raw produce has increased dramatically. To understand how Salmonella adapts to produce, transcriptomic analysis was conducted on Salmonella enterica serovar Virchow exposed to fresh-cut radish greens. Considering the different Salmonella lifestyles in contact with fresh produce, such as motile and sessile lifestyles, total RNA was extracted from planktonic and epiphytic cells separately. Transcriptomic analysis of S. Virchow cells revealed different transcription profiles between lifestyles. During bacterial adaptation to fresh-cut radish greens, planktonic cells were likely to shift toward anaerobic metabolism, exploiting nitrate as an electron acceptor of anaerobic respiration, and utilizing cobalamin as a cofactor for coupled metabolic pathways. Meanwhile, Salmonella cells adhering to plant surfaces showed coordinated upregulation in genes associated with translation and ribosomal biogenesis, indicating dramatic cellular reprogramming in response to environmental changes. In accordance with the extensive translational response, epiphytic cells showed an increase in the transcription of genes that are important for bacterial motility, nucleotide transporter/metabolism, cell envelope biogenesis, and defense mechanisms. Intriguingly, Salmonella pathogenicity island (SPI)-1 and SPI-2 displayed up- and downregulation, respectively, regardless of lifestyles in contact with the radish greens, suggesting altered Salmonella virulence during adaptation to plant environments. This study provides molecular insights into Salmonella adaptation to plants as an alternative environmental reservoir.
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Affiliation(s)
- Sojung Park
- Department of Molecular Science and Technology, Ajou University, Suwon6499, Republic of Korea
| | - Eun woo Nam
- Department of Molecular Science and Technology, Ajou University, Suwon6499, Republic of Korea
| | - Yeeun Kim
- Department of Molecular Science and Technology, Ajou University, Suwon6499, Republic of Korea
| | - Seohyeon Lee
- Department of Applied Chemistry and Biological Engineering, Ajou University, Suwon16499 Republic of Korea
| | - Seul I Kim
- Department of Molecular Science and Technology, Ajou University, Suwon6499, Republic of Korea
| | - Hyunjin Yoon
- Department of Molecular Science and Technology, Ajou University, Suwon6499, Republic of Korea,Department of Applied Chemistry and Biological Engineering, Ajou University, Suwon16499 Republic of Korea,Corresponding author Phone: +82-31-219-2450 Fax: +82-31-219-1610 E-mail:
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Yan Y, Wang W, Wu M, Jetten MSM, Guo J, Ma J, Wang H, Dai X, Wang Y. Transcriptomics Uncovers the Response of Anammox Bacteria to Dissolved Oxygen Inhibition and the Subsequent Recovery Mechanism. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:14674-14685. [PMID: 33147001 DOI: 10.1021/acs.est.0c02842] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Understanding the recovery of anaerobic ammonium-oxidizing (anammox) bacteria after inhibition by dissolved oxygen (DO) is critical for the successful applications of anammox-based processes. Therefore, the effects of oxygen exposure (2 mg L-1 DO for 90 min) and subsequent recovery treatments [N2 purging or nano zero-valent iron (nZVI) addition] on the activity and gene expression in a Kuenenia stuttgartiensis enrichment culture were examined. Combining the self-organizing map clustering and enrichment analysis, we proposed the oxidative stress response of anammox bacteria based on the existing concepts of oxidative stress in microbes: the DO exposure triggered a stringent response in K. stuttgartiensis, which downregulated the transcription levels of genes involved in the central metabolism and diverted energy to a flagellar assembly and metal transport modules; these changes possibly promoted survival during the inhibition of anammox activity. According to the cotranscription with central catabolism genes, putative reactive oxygen species (ROS) scavenger genes (kat and sod) were presumed to detoxify the anammox intermediates rather than ROS. In addition, both activity and mRNA profiles with appropriate amount of nZVI addition (5 and 25 mg L-1) were close to that of control, which proved the effectiveness of nZVI addition in anammox recovery. These results would be relevant to the physio-biochemistry development of anammox bacteria and further enhancement of nitrogen removal in wastewater treatment.
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Affiliation(s)
- Yuan Yan
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P. R. China
| | - Weigang Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P. R. China
| | - Mengxiong Wu
- Advanced Water Management Centre (AWMC), The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | - Mike S M Jetten
- Microbiology, IWWR, Faculty of Science, Radboud University Nijmegen, Heyendaalseweg 135, AJ Nijmegen 6525, The Netherlands
| | - Jianhua Guo
- Advanced Water Management Centre (AWMC), The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | - Jie Ma
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P. R. China
| | - Han Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P. R. China
| | - Xiaohu Dai
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P. R. China
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, P. R. China
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Gran-Scheuch A, Ramos-Zuñiga J, Fuentes E, Bravo D, Pérez-Donoso JM. Effect of Co-contamination by PAHs and Heavy Metals on Bacterial Communities of Diesel Contaminated Soils of South Shetland Islands, Antarctica. Microorganisms 2020; 8:microorganisms8111749. [PMID: 33171767 PMCID: PMC7695015 DOI: 10.3390/microorganisms8111749] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/26/2020] [Accepted: 10/31/2020] [Indexed: 01/04/2023] Open
Abstract
Diesel oil is the main source of energy used in Antarctica. Since diesel is composed of toxic compounds such as polycyclic aromatic hydrocarbons (PAHs) and heavy metals, it represents a constant threat to the organisms inhabiting this continent. In the present study, we characterized the chemical and biological parameters of diesel-exposed soils obtained from King George Island in Antarctica. Contaminated soils present PAH concentrations 1000 times higher than non-exposed soils. Some contaminated soil samples also exhibited high concentrations of cadmium and lead. A 16S metagenome analysis revealed the effect of co-contamination on bacterial communities. An increase in the relative abundance of bacteria known as PAH degraders or metal resistant was determined in co-contaminated soils. Accordingly, the soil containing higher amounts of PAHs exhibited increased dehydrogenase activity than control soils, suggesting that the microorganisms present can metabolize diesel. The inhibitory effect on soil metabolism produced by cadmium was lower in diesel-contaminated soils. Moreover, diesel-contaminated soils contain higher amounts of cultivable heterotrophic, cadmium-tolerant, and PAH-degrading bacteria than control soils. Obtained results indicate that diesel contamination at King George island has affected microbial communities, favoring the presence of microorganisms capable of utilizing PAHs as a carbon source, even in the presence of heavy metals.
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Affiliation(s)
- Alejandro Gran-Scheuch
- BioNanotechnology and Microbiology Lab, Center for Bioinformatics and Integrative Biology (CBIB), Facultad de Ciencias de la Vida, Universidad Andres Bello, Republica # 330, Santiago 8370146, Chile; (A.G.-S.); (J.R.-Z.)
- Departamento de Química Inorgánica y Analítica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Sergio Livingstone Pohlhammer # 1007, Santiago 8380000, Chile;
| | - Javiera Ramos-Zuñiga
- BioNanotechnology and Microbiology Lab, Center for Bioinformatics and Integrative Biology (CBIB), Facultad de Ciencias de la Vida, Universidad Andres Bello, Republica # 330, Santiago 8370146, Chile; (A.G.-S.); (J.R.-Z.)
| | - Edwar Fuentes
- Departamento de Química Inorgánica y Analítica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Sergio Livingstone Pohlhammer # 1007, Santiago 8380000, Chile;
| | - Denisse Bravo
- Laboratorio de Microbiología Oral, Facultad de Odontología, Universidad de Chile, Sergio Livingstone Pohlhammer # 943, Santiago 8380453, Chile;
| | - José M. Pérez-Donoso
- BioNanotechnology and Microbiology Lab, Center for Bioinformatics and Integrative Biology (CBIB), Facultad de Ciencias de la Vida, Universidad Andres Bello, Republica # 330, Santiago 8370146, Chile; (A.G.-S.); (J.R.-Z.)
- Correspondence:
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Kumar SB, Arnipalli SR, Ziouzenkova O. Antibiotics in Food Chain: The Consequences for Antibiotic Resistance. Antibiotics (Basel) 2020; 9:antibiotics9100688. [PMID: 33066005 PMCID: PMC7600537 DOI: 10.3390/antibiotics9100688] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 09/28/2020] [Accepted: 10/08/2020] [Indexed: 12/14/2022] Open
Abstract
Antibiotics have been used as essential therapeutics for nearly 100 years and, increasingly, as a preventive agent in the agricultural and animal industry. Continuous use and misuse of antibiotics have provoked the development of antibiotic resistant bacteria that progressively increased mortality from multidrug-resistant bacterial infections, thereby posing a tremendous threat to public health. The goal of our review is to advance the understanding of mechanisms of dissemination and the development of antibiotic resistance genes in the context of nutrition and related clinical, agricultural, veterinary, and environmental settings. We conclude with an overview of alternative strategies, including probiotics, essential oils, vaccines, and antibodies, as primary or adjunct preventive antimicrobial measures or therapies against multidrug-resistant bacterial infections. The solution for antibiotic resistance will require comprehensive and incessant efforts of policymakers in agriculture along with the development of alternative therapeutics by experts in diverse fields of microbiology, biochemistry, clinical research, genetic, and computational engineering.
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Muñoz-Villagrán C, Contreras F, Cornejo F, Figueroa M, Valenzuela-Bezanilla D, Luraschi R, Reinoso C, Rivas-Pardo J, Vásquez C, Castro M, Arenas F. Understanding gold toxicity in aerobically-grown Escherichia coli. Biol Res 2020; 53:26. [PMID: 32513271 PMCID: PMC7278051 DOI: 10.1186/s40659-020-00292-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 05/16/2020] [Indexed: 12/03/2022] Open
Abstract
Background There is an emerging field to put into practice new strategies for developing molecules with antimicrobial properties. In this line, several metals and metalloids are currently being used for these purposes, although their cellular effect(s) or target(s) in a particular organism are still unknown. Here we aimed to investigate and analyze Au3+ toxicity through a combination of biochemical and molecular approaches. Results We found that Au3+ triggers a major oxidative unbalance in Escherichia coli, characterized by decreased intracellular thiol levels, increased superoxide concentration, as well as by an augmented production of the antioxidant enzymes superoxide dismutase and catalase. Because ROS production is, in some cases, associated with metal reduction and the concomitant generation of gold-containing nanostructures (AuNS), this possibility was evaluated in vivo and in vitro. Conclusions Au3+ is toxic for E. coli because it triggers an unbalance of the bacterium’s oxidative status. This was demonstrated by using oxidative stress dyes and antioxidant chemicals as well as gene reporters, RSH concentrations and AuNS generation.
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Affiliation(s)
- C Muñoz-Villagrán
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - F Contreras
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - F Cornejo
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - M Figueroa
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - D Valenzuela-Bezanilla
- Laboratorio de Microbiología Aplicada, Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad Santo Tomás, Sede Santiago, Chile
| | - R Luraschi
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - C Reinoso
- Laboratorio de Microbiología Aplicada, Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad Santo Tomás, Sede Santiago, Chile
| | - J Rivas-Pardo
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile.,Laboratorio de Biología estructural, Centro de Genómica y Bioinformática, Universidad Mayor, Santiago, Chile
| | - C Vásquez
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - M Castro
- Laboratorio de Microbiología Aplicada, Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad Santo Tomás, Sede Santiago, Chile.
| | - F Arenas
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile.
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Orizola J, Ríos-Silva M, Muñoz-Villagrán C, Vargas E, Vásquez C, Arenas F. In vitro biosynthesis of Ag, Au and Te-containing nanostructures by Exiguobacterium cell-free extracts. BMC Biotechnol 2020; 20:29. [PMID: 32471409 PMCID: PMC7260758 DOI: 10.1186/s12896-020-00625-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 05/21/2020] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND The bacterial genus Exiguobacterium includes several species that inhabit environments with a wide range of temperature, salinity, and pH. This is why the microorganisms from this genus are known generically as polyextremophiles. Several environmental isolates have been explored and characterized for enzyme production as well as for bioremediation purposes. In this line, toxic metal(loid) reduction by these microorganisms represents an approach to decontaminate soluble metal ions via their transformation into less toxic, insoluble derivatives. Microbial-mediated metal(loid) reduction frequently results in the synthesis of nanoscale structures-nanostructures (NS) -. Thus, microorganisms could be used as an ecofriendly way to get NS. RESULTS We analyzed the tolerance of Exiguobacterium acetylicum MF03, E. aurantiacum MF06, and E. profundum MF08 to Silver (I), gold (III), and tellurium (IV) compounds. Specifically, we explored the ability of cell-free extracts from these bacteria to reduce these toxicants and synthesize NS in vitro, both in the presence or absence of oxygen. All isolates exhibited higher tolerance to these toxicants in anaerobiosis. While in the absence of oxygen they showed high tellurite- and silver-reducing activity at pH 9.0, whereas AuCl4- which was reduced at pH 7.0 in both conditions. Given these results, cell-free extracts were used to synthesize NS containing silver, gold or tellurium, characterizing their size, morphology and chemical composition. Silver and tellurium NS exhibited smaller size under anaerobiosis and their morphology was circular (silver NS), starred (tellurium NS) or amorphous (gold NS). CONCLUSIONS This nanostructure-synthesizing ability makes these isolates interesting candidates to get NS with biotechnological potential.
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Affiliation(s)
- Javier Orizola
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Mirtha Ríos-Silva
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile.,Departamento de Ciencias Nucleares, Comisión Chilena de Energía Nuclear, Santiago, Chile
| | - Claudia Muñoz-Villagrán
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Esteban Vargas
- Center for the Development of Nanoscience and Nanotechnology, Santiago, Chile
| | - Claudio Vásquez
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Felipe Arenas
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile.
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Ali P, Shah AA, Hasan F, Hertkorn N, Gonsior M, Sajjad W, Chen F. A Glacier Bacterium Produces High Yield of Cryoprotective Exopolysaccharide. Front Microbiol 2020; 10:3096. [PMID: 32117080 PMCID: PMC7026135 DOI: 10.3389/fmicb.2019.03096] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 12/20/2019] [Indexed: 12/21/2022] Open
Abstract
Pseudomonas sp. BGI-2 is a psychrotrophic bacterium isolated from the ice sample collected from Batura glacier, Pakistan. This strain produces highly viscous colonies on agar media supplemented with glucose. In this study, we have optimized growth and production of exopolysaccharide (EPS) by the cold-adapted Pseudomonas sp. BGI-2 using different nutritional and environmental conditions. Pseudomonas sp. BGI-2 is able to grow in a wide range of temperatures (4-35°C), pH (5-11), and salt concentrations (1-5%). Carbon utilization for growth and EPS production was extensively studied and we found that glucose, galactose, mannose, mannitol, and glycerol are the preferable carbon sources. The strain is also able to use sugar waste molasses as a growth substrate, an alternative for the relatively expensive sugars for large scale EPS production. Maximum EPS production was observed at 15°C, pH 6, NaCl (10 g L-1), glucose as carbon source (100 g L-1), yeast extract as nitrogen source (10 g L-1), and glucose/yeast extract ratio (10/1). Under optimized conditions, EPS production was 2.01 g L-1, which is relatively high for a Pseudomonas species compared to previous studies using the same method for quantification. High-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) analysis of EPS revealed glucose, galactose, and glucosamine as the main sugar monomers. Membrane protection assay using human RBCs revealed significant reduction in cell lysis (∼50%) in the presence of EPS, suggesting its role in membrane protection. The EPS (5%) also conferred significant cryoprotection for a mesophilic Escherichia coli k12 which was comparable to glycerol (20%). Also, improvement in lipid peroxidation inhibition (in vitro) resulted when lipids from the E. coli was pretreated with EPS. Increased EPS production at low temperatures, freeze thaw tolerance of the EPS producing strain, and increased survivability of E. coli in the presence of EPS as cryoprotective agent supports the hypothesis that EPS production is a strategy for survival in extremely cold environments such as the glacier ice.
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Affiliation(s)
- Pervaiz Ali
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD, United States
- Applied Environmental and Geomicrobiology Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Aamer Ali Shah
- Applied Environmental and Geomicrobiology Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Fariha Hasan
- Applied Environmental and Geomicrobiology Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Norbert Hertkorn
- Research Unit Analytical Biogeochemistry, Helmholtz Zentrum München, Munich, Germany
| | - Michael Gonsior
- Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science, Baltimore, MD, United States
| | - Wasim Sajjad
- Department of Biological Sciences, National University of Medical Sciences, Rawalpindi, Pakistan
| | - Feng Chen
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD, United States
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A novel Xanthomonas citri subsp. citri NADPH quinone reductase involved in salt stress response and virulence. Biochim Biophys Acta Gen Subj 2020; 1864:129514. [PMID: 31911239 DOI: 10.1016/j.bbagen.2020.129514] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 12/20/2019] [Accepted: 12/30/2019] [Indexed: 12/21/2022]
Abstract
BACKGROUND Xanthomonas citri subsp. citri (Xcc), the causal agent of citrus canker is maintained as an epiphyte on citrus leaves until entering the plant tissue. During epiphytic survival, bacteria may encounter low water availability that challenges the infection process. Proteomics analyses of Xcc under saline stress, mimicking the conditions found during epiphytic survival, showed increased abundance of a putative NAD(P)H dehydrogenase encoded by XAC2229. METHODS Expression levels of XAC2229 and a Xcc mutant in XAC2229 were analyzed in salt and oxidative stress and during plant-pathogen interaction. An Escherichia coli expressing XAC2229 was obtained, and the role of this protein in oxidative stress resistance and in reactive oxygen species production was studied. Finally, Xac2229 protein was purified, spectrophotometric and cofactor analyses were done and enzymatic activities determined. RESULTS XAC2229 was expressed under salt stress and during plant-pathogen interaction. ΔXAC2229 mutant showed less number of cankers and impaired epiphytic survival than the wild type strain. ΔXAC2229 survived less in the presence of H2O2 and produced more reactive oxygen species and thiobarbituric acid-reactive substances than the wild type strain. Similar results were observed for E. coli expressing XAC2229. Xac2229 is a FAD containing flavoprotein, displays diaphorase activity with an optimum at pH 6.0 and has quinone reductase activity using NADPH as an electron donor. CONCLUSIONS A FAD containing flavoprotein from Xcc is a new NADPH quinone reductase required for bacterial virulence, particularly in Xcc epiphytic survival on citrus leaves. GENERAL SIGNIFICANCE A novel protein involved in the worldwide disease citrus canker was characterized.
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Khan T, Ali GS. Variation in surface properties, metabolic capping, and antibacterial activity of biosynthesized silver nanoparticles: comparison of bio-fabrication potential in phytohormone-regulated cell cultures and naturally grown plants. RSC Adv 2020; 10:38831-38840. [PMID: 35518444 PMCID: PMC9057356 DOI: 10.1039/d0ra08419k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/09/2020] [Accepted: 10/15/2020] [Indexed: 12/04/2022] Open
Abstract
We compared surface properties, metabolic capping and antibacterial activity of silver nanoparticles, synthesized through extracts of cell cultures of Fagonia indica and its naturally grown form. Extracts from cell cultures (produced with thidiazuron (TDZ) or melatonin (MLN)) were compared to the naturally grown whole plant extracts (WPEs) for their reducing potential, and their effects on physical and biochemical properties of the biosynthesized silver nanoparticles. UV-Vis spectroscopy revealed that the surface plasmon resonance peaked at λ = 415 nm for MLN-AgNPs, λ = 430 nm for TDZ-AgNPs and λ = 460–465 nm for WPE-AgNPs. Transmission electron microscopy and energy dispersive X-rays of AgNPs showed that compared to WPE-AgNPs (mean diameter = 22 nm), extracts from MLN- and TDZ-induced cell cultures produced particles with spherical shapes and smaller diameters (i.e. mean diameter = 15 nm and 19 nm, respectively). Size distribution analysis also showed that TDZ-AgNPs were nearer to a symmetric distribution in terms of diameter (skewness = 0.80) as compared to WPE-AgNPs (skewness = 0.9) and MLN-AgNPs (skewness = 1.4). Furthermore, MLN-induced cell culture extracts produced AgNPs in higher concentration (210 μg mL−1) compared to AgNPs from TDZ-induced cell culture extracts (160 μg mL−1) and WPE (138 μg mL−1). Two-way comparisons of LC-MS/MS profiles of TDZ-AgNPs, MLN-AgNPs, and WPE-AgNPs revealed differences in their secondary metabolite profiles, which might account for differences in their differential response in bio-fabrication, and size distribution. Activity against different pathogenic bacterial strains, Escherichia coli, Bacillus cereus, Xanthomonas citri, Agrobacterium tumefaciens, Streptomyces griseus, and Erwinia carotovora suggested that MLN-AgNPs were more effective compared to TDZ- and WPE-AgNPs. These results indicated that phytohormones induced cell cultures can enhance the production, physical and biochemical properties of AgNPs. We compared surface properties, metabolic capping and antibacterial activity of biosynthesized silver nanoparticles, synthesized through extracts of cell cultures of Fagonia indica and its naturally grown form.![]()
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Affiliation(s)
- Tariq Khan
- Department of Biotechnology
- University of Malakand
- Pakistan
- Plant Molecular and Cell Biology
- Department of Plant Pathology
| | - Gul Shad Ali
- Plant Molecular and Cell Biology
- Department of Plant Pathology
- Mid-Florida Research and Education Center
- University of Florida/Institute of Food and Agricultural Sciences
- Apopka
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Munar MP, Takahashi H, Okamura Y. Discovery of a Novel Gene Conferring Tellurite Tolerance Through Tellurite Reduction to Escherichia coli Transformant in Marine Sediment Metagenomic Library. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2019; 21:762-772. [PMID: 31637558 DOI: 10.1007/s10126-019-09922-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 09/02/2019] [Indexed: 06/10/2023]
Abstract
Metagenomic library construction using a marine sediment-enrichment was employed in order to recover tellurium from tellurite, a tellurium oxyanion, dissolved in water and then functional screening was performed to discover a novel gene related to tellurite reduction. Transmission electron microscopy (TEM) revealed the formation of intracellular Te crystals in Escherichia coli cells transformed with a specific DNA fragment from the marine sediment metagenome. The metagenome fragment was composed of 691 bp and showed low homology to known proteins. Phylogenetic analysis suggested that the metagenome fragment was related to Pseudomonas stutzeri. Cloning and expression of an open reading frame (ORF) on the metagenome fragment validated the role of the fragment in conferring tellurite resistance and tellurite-reducing activity to E. coli host cells. E. coli transformant containing the ORF1 showed resistance to 1 mM Na2TeO3. The optimal tellurite-reducing activity of cells containing the ORF1 was recorded at 37 °C and pH 7.0.
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Affiliation(s)
- Madison Pascual Munar
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Hiroshima, Japan
| | - Hirokazu Takahashi
- Unit of Biotechnology, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Yoshiko Okamura
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Hiroshima, Japan.
- Unit of Biotechnology, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan.
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Behzadpour N, Sattarahmady N, Akbari N. Antimicrobial Photothermal Treatment of Pseudomonas Aeruginosa by a Carbon Nanoparticles-Polypyrrole Nanocomposite. J Biomed Phys Eng 2019; 9:661-672. [PMID: 32039097 PMCID: PMC6943850 DOI: 10.31661/jbpe.v0i0.1024] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 10/30/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND Nowadays, it is needed to explore new routes to treat infectious bacterial pathogens due to prevalence of antibiotic-resistant bacteria. Antimicrobial photothermal therapy (PTT), as a new strategy, eradicates pathogenic bacteria. OBJECTIVE In this study, the antimicrobial effects of a carbon nanoparticles-polypyrrole nanocomposite (C-PPy) upon laser irradiation were investigated to destroy the pathogenic gram-negative Pseudomonas aeruginosa. MATERIAL AND METHODS In this experimental study, the bacterial cells were incubated with 50, 100 and 250 µg mL-1 concentrations of C-PPy and irradiated with a 808-nm laser at two power densities of 0.5 and 1.0 W cm-2. CFU numbers were counted for the irradiated cells, and compared to an untreated sample (kept in dark). To explore the antibacterial properties and mechanism(s) of C-PPy, temperature increment, reactive oxygen species formation, and protein and DNA leakages were evaluated. Field emission scanning electron microscopy was also employed to investigate morphological changes in the bacterial cell structures. RESULTS The results showed that following C-PPy attachment to the bacteria surface, irradiation of near-infrared light resulted in a significant decrement in the bacterial cell viability due to photothermal lysis. Slightly increase in protein leakage and significantly increase intracellular reactive oxygen species (ROS) were observed in the bacteria upon treating with C-PPy. CONCLUSION Photo-ablation strategy is a new minimally invasive and inexpensive method without overdose risk manner for combat with bacteria.
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Affiliation(s)
- N Behzadpour
- MSc, Department of Medical Physics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
- MSc, Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - N Sattarahmady
- PhD, Department of Medical Physics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
- PhD, Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - N Akbari
- PhD, Department of Microbiology, Faculty of Science, Arak Branch, Islamic Azad University, Arak, Iran
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Extreme Environments and High-Level Bacterial Tellurite Resistance. Microorganisms 2019; 7:microorganisms7120601. [PMID: 31766694 PMCID: PMC6955997 DOI: 10.3390/microorganisms7120601] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 11/19/2019] [Accepted: 11/20/2019] [Indexed: 01/10/2023] Open
Abstract
Bacteria have long been known to possess resistance to the highly toxic oxyanion tellurite, most commonly though reduction to elemental tellurium. However, the majority of research has focused on the impact of this compound on microbes, namely E. coli, which have a very low level of resistance. Very little has been done regarding bacteria on the other end of the spectrum, with three to four orders of magnitude greater resistance than E. coli. With more focus on ecologically-friendly methods of pollutant removal, the use of bacteria for tellurite remediation, and possibly recovery, further highlights the importance of better understanding the effect on microbes, and approaches for resistance/reduction. The goal of this review is to compile current research on bacterial tellurite resistance, with a focus on high-level resistance by bacteria inhabiting extreme environments.
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Behzadpour N, Akbari N, Sattarahmady N. Photothermal inactivation of methicillin-resistant Staphylococcus aureus: anti-biofilm mediated by a polypyrrole-carbon nanocomposite. IET Nanobiotechnol 2019; 13:800-807. [PMID: 31625519 PMCID: PMC8676018 DOI: 10.1049/iet-nbt.2018.5340] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 01/01/2019] [Accepted: 02/07/2019] [Indexed: 04/05/2024] Open
Abstract
Widespread resistance to antibiotics amongst pathogens has become a tremendous challenge of high morbidity and mortality rates which increases the needs to exploring novel methods of treatment. An efficient antimicrobial procedure to root out pathogenic bacteria is photothermal therapy. In this study, antimicrobial effects of a polypyrrole-carbon nanocomposite (PPy-C) upon laser irradiation in order to destroy the pathogenic gram-positive bacterium, methicillin-resistant Staphylococcus aureus (MRSA) were assessed. The bacterial cells were incubated with 500, 750 and 1000 μg ml-1 concentrations of PPy-C and irradiated with an 808-nm laser at a power density of 1.0 W cm-2. To indicate the biocompatibility and toxic effect of the nanocomposite without and with laser irradiation, the authors counted the number of CFUs and compared it to an untreated sample. Antibacterial mechanisms of PPy-C were assessed through temperature increment, reactive oxygen species production, and protein and DNA leakages. Photothermal heating assay showed that 26°C temperature increases in the presence of 1000 µg ml-1 PPy-C led to >98% killing of MRSA. Furthermore, 20 min radiation of near-infrared light to PPy-C in different concentrations indicated destruction and reduction in the MRSA biofilm formation. Therefore, PPy-C was introduced as a photothermal absorber with a bactericidal effect in MRSA.
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Affiliation(s)
- Niloufar Behzadpour
- Department of Medical Physics, School of Medicine, Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Neda Akbari
- Department of Microbiology, Faculty of Science, Arak Branch, Islamic Azad University, Arak, Iran
| | - Naghmeh Sattarahmady
- Department of Medical Physics, School of Medicine, Nanomedicine and Nanobiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
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Hews CL, Pritchard EJ, Rowley G. The Salmonella Specific, σ E-Regulated, STM1250 and AgsA, Function With the sHsps IbpA and IbpB, to Counter Oxidative Stress and Survive Macrophage Killing. Front Cell Infect Microbiol 2019; 9:263. [PMID: 31396489 PMCID: PMC6663981 DOI: 10.3389/fcimb.2019.00263] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 07/04/2019] [Indexed: 11/13/2022] Open
Abstract
The host presents an array of environments which induce bacterial stress including changes in pH, antimicrobial compounds and reactive oxygen species. The bacterial envelope sits at the interface between the intracellular and extracellular environment and its maintenance is essential for Salmonella cell viability under a range of conditions, including during infection. In this study, we aimed to understand the contribution of the σH- and σE-regulated small heat shock proteins IbpA, IbpB, and AgsA and the putative σE-regulated stress response protein STM1250 to the Salmonella envelope stress response. Due to shared sequence identity, regulatory overlap, and the specificity of STM1250 and AgsA to Salmonella sp., we hypothesized that functional overlap exists between these four stress response proteins, which might afford a selective advantage during Salmonella exposure to stress. We present here new roles for three small heat shock proteins and a putative stress response protein in Salmonella that are not limited to heat shock. We have shown that, compared to WT, a quadruple mutant is significantly more sensitive to hydrogen peroxide, has a lower minimum bactericidal concentration to the cationic antimicrobial peptide polymyxin B, and is attenuated in macrophages.
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Affiliation(s)
- Claire L Hews
- School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Emily J Pritchard
- School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Gary Rowley
- School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
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Medina Cruz D, Tien-Street W, Zhang B, Huang X, Vernet Crua A, Nieto-Argüello A, Cholula-Díaz JL, Martínez L, Huttel Y, Ujué González M, García-Martín JM, Webster TJ. Citric Juice-mediated Synthesis of Tellurium Nanoparticles with Antimicrobial and Anticancer Properties. GREEN CHEMISTRY : AN INTERNATIONAL JOURNAL AND GREEN CHEMISTRY RESOURCE : GC 2019; 21:1982-1988. [PMID: 31156349 PMCID: PMC6542685 DOI: 10.1039/c9gc00131j] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Bacterial infections and cancer are two of the most significant concerns that the current healthcare system should tackle nowadays. Green nanotechnology is presented as a feasible solution that is able to produce materials with significant anticancer and antibacterial activity, while overcoming the main limitations of traditional synthesis. In the present work, orange, lemon and lime extracts were used as both reducing and capping agents for the green synthesis of tellurium nanoparticles (TeNPs) using a microwave-assisted reaction. TeNPs showed a uniform size distribution, and rod- and cubic-shapes, and were extensively characterized in terms of morphology, structure and composition using TEM, SEM, XPS, XRD, FTIR and EDX analysis. TeNPs showed an important antibacterial activity against both Gram-negative and -positive bacteria in a range concentrations from 5 to 50 μg/mL over a 24-hour time period. Besides, nanoparticles showed anticancer effect towards human melanoma cells over 48 hours at concentrations up to 50 μg/mL. Moreover, the Te nanostructures showed no significant cytotoxic effect towards human dermal fibroblast at concentrations up to 50 μg/mL. Therefore, we present an environmentally-friendly and cost-effective synthesis of TeNPs using only fruit juices and showing enhanced and desirable biomedical properties towards both infectious diseases and cancer.
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Affiliation(s)
- David Medina Cruz
- Department of Chemical Engineering, Northeastern University, Boston, MA 02115, USA
| | - William Tien-Street
- Department of Chemical Engineering, Northeastern University, Boston, MA 02115, USA
- Department of Bioengineering, Northeastern University, Boston, MA 02115, USA
| | - Bohan Zhang
- Department of Chemical Engineering, Northeastern University, Boston, MA 02115, USA
| | - Xinjing Huang
- Department of Chemical Engineering, Northeastern University, Boston, MA 02115, USA
| | - Ada Vernet Crua
- Department of Chemical Engineering, Northeastern University, Boston, MA 02115, USA
| | - Alfonso Nieto-Argüello
- School of Engineering and Sciences, Tecnologico de Monterrey, Av. Eugenio Garza Sada 2501, Monterrey, NL 64849, Mexico
| | - Jorge L. Cholula-Díaz
- School of Engineering and Sciences, Tecnologico de Monterrey, Av. Eugenio Garza Sada 2501, Monterrey, NL 64849, Mexico
| | - Lidia Martínez
- Materials Science Factory. Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC, Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
| | - Yves Huttel
- Materials Science Factory. Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC, Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
| | - María Ujué González
- Instituto de Micro y Nanotecnología, IMN-CNM, CSIC (CEI UAM+CSIC), Isaac Newton 8, 28760 Tres Cantos, Spain
| | - José Miguel García-Martín
- Instituto de Micro y Nanotecnología, IMN-CNM, CSIC (CEI UAM+CSIC), Isaac Newton 8, 28760 Tres Cantos, Spain
| | - Thomas J. Webster
- Department of Chemical Engineering, Northeastern University, Boston, MA 02115, USA
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Contreras F, Vargas E, Jiménez K, Muñoz-Villagrán C, Figueroa M, Vásquez C, Arenas F. Reduction of Gold (III) and Tellurium (IV) by Enterobacter cloacae MF01 Results in Nanostructure Formation Both in Aerobic and Anaerobic Conditions. Front Microbiol 2018; 9:3118. [PMID: 30619192 PMCID: PMC6305273 DOI: 10.3389/fmicb.2018.03118] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Accepted: 12/03/2018] [Indexed: 12/22/2022] Open
Abstract
Microorganism survival in the presence of toxic substances such as metal(loid)s lies chiefly on their ability to resist (or tolerate) such elements through specific resistance mechanisms. Among them, toxicant reduction has attracted the attention of researchers because metal(loid)-reducing bacteria are being used to recover and/or decontaminate polluted sites. Particularly, our interest is to analyze the toxicity of gold and tellurium compounds for the environmental microorganism Enterobacter cloacae MF01 and also to explore the generation of nanostructures to be used in future biotechnological processes. Resistance of E. cloacae MF01 to gold and tellurium salts as well as the putative mechanisms involved -both in aerobic and anaerobic growth conditions- was evaluated. These metal(loid)s were selected because of their potential application in biotechnology. Resistance to auric tetrachloride acid (HAuCl4) and potassium tellurite (K2TeO3) was assessed by determining areas of growth inhibition, minimum inhibitory concentrations, and growth curves as well as by viability tests. E. cloacae MF01 exhibited higher resistance to HAuCl4 and K2TeO3 under aerobic and anaerobic conditions, respectively. In general, their toxicity is mediated by the generation of reactive oxygen species and by a decrease of intracellular reduced thiols (RSH). To assess if resistance implies toxicant reduction, intra- and extra-cellular toxicant-reducing activities were evaluated. While E. cloacae MF01 exhibited intra- and extra-cellular HAuCl4-reducing activity, tellurite reduction was observed only intracellularly. Then, Au- and Te-containing nanostructures (AuNS and TeNS, respectively) were synthesized using crude extracts from E. cloacae MF01 and their size, morphology, and chemical composition was evaluated.
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Affiliation(s)
- Fernanda Contreras
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Esteban Vargas
- Center for the Development of Nanoscience and Nanotechnology, Santiago, Chile
| | - Karla Jiménez
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Claudia Muñoz-Villagrán
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile.,Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad Santo Tomás, Santiago, Chile
| | - Maximiliano Figueroa
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Claudio Vásquez
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Felipe Arenas
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
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Figueroa M, Fernandez V, Arenas-Salinas M, Ahumada D, Muñoz-Villagrán C, Cornejo F, Vargas E, Latorre M, Morales E, Vásquez C, Arenas F. Synthesis and Antibacterial Activity of Metal(loid) Nanostructures by Environmental Multi-Metal(loid) Resistant Bacteria and Metal(loid)-Reducing Flavoproteins. Front Microbiol 2018; 9:959. [PMID: 29869640 PMCID: PMC5962736 DOI: 10.3389/fmicb.2018.00959] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 04/24/2018] [Indexed: 12/13/2022] Open
Abstract
Microbes are suitable candidates to recover and decontaminate different environments from soluble metal ions, either via reduction or precipitation to generate insoluble, non-toxic derivatives. In general, microorganisms reduce toxic metal ions generating nanostructures (NS), which display great applicability in biotechnological processes. Since the molecular bases of bacterial reduction are still unknown, the search for new -environmentally safe and less expensive- methods to synthesize NS have made biological systems attractive candidates. Here, 47 microorganisms isolated from a number of environmental samples were analyzed for their tolerance or sensitivity to 19 metal(loid)s. Ten of them were highly tolerant to some of them and were assessed for their ability to reduce these toxicants in vitro. All isolates were analyzed by 16S rRNA gene sequencing, fatty acids composition, biochemical tests and electron microscopy. Results showed that they belong to the Enterobacter, Staphylococcus, Acinetobacter, and Exiguobacterium genera. Most strains displayed metal(loid)-reducing activity using either NADH or NADPH as cofactor. While Acinetobacter schindleri showed the highest tellurite ( TeO32- ) and tetrachloro aurate ( AuCl4- ) reducing activity, Staphylococcus sciuri and Exiguobacterium acetylicum exhibited selenite ( SeO32- ) and silver (Ag+) reducing activity, respectively. Based on these results, we used these bacteria to synthetize, in vivo and in vitro Te, Se, Au, and Ag-containing nanostructures. On the other hand, we also used purified E. cloacae glutathione reductase to synthesize in vitro Te-, Ag-, and Se-containing NS, whose morphology, size, composition, and chemical composition were evaluated. Finally, we assessed the putative anti-bacterial activity exhibited by the in vitro synthesized NS: Te-containing NS were more effective than Au-NS in inhibiting Escherichia coli and Listeria monocytogenes growth. Aerobically synthesized TeNS using MF09 crude extracts showed MICs of 45- and 66- μg/ml for E. coli and L. monocytogenes, respectively. Similar MIC values (40 and 82 μg/ml, respectively) were observed for TeNS generated using crude extracts from gorA-overexpressing E. coli. In turn, AuNS MICs for E. coli and L. monocytogenes were 64- and 68- μg/ml, respectively.
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Affiliation(s)
- Maximiliano Figueroa
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Valentina Fernandez
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | | | - Diego Ahumada
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Claudia Muñoz-Villagrán
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile.,Departamento de Ciencias Básicas, Facultad de Ciencia, Universidad Santo Tomas, Sede Santiago, Chile
| | - Fabián Cornejo
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Esteban Vargas
- Center for the Development of Nanoscience and Nanotechnology, Santiago, Chile
| | - Mauricio Latorre
- Mathomics, Centro de Modelamiento Matemático, Universidad de Chile, Beauchef, Santiago, Chile.,Fondap-Center of Genome Regulation, Facultad de Ciencias, Universidad de Chile, Santiago, Chile.,Laboratorio de Bioinformática y Expresión Génica, INTA, Universidad de Chile, Santiago, Chile.,Instituto de Ciencias de la Ingeniería, Universidad de O'Higgins, Rancagua, Chile
| | | | - Claudio Vásquez
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Felipe Arenas
- Laboratorio Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
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44
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Goff J, Yee N. Tellurate enters Escherichia coli K-12 cells via the SulT-type sulfate transporter CysPUWA. FEMS Microbiol Lett 2018; 364:4597602. [PMID: 29126297 DOI: 10.1093/femsle/fnx241] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 11/04/2017] [Indexed: 11/14/2022] Open
Abstract
Soluble forms of tellurium are environmental contaminants that are toxic to microorganisms. While tellurite [Te(IV)] is a well-characterized antimicrobial agent, little is known about the interactions of tellurate [Te(VI)] with bacterial cells. In this study, we investigated the role of sulfate transporters in the uptake of tellurate in Escherichia coli K-12. Mutant strains carrying a deletion of the cysW gene in the CysPUWA sulfate transporter system accumulated less cellular tellurium and exhibited higher resistance to tellurate compared with the wild-type strain. Complementation of the mutation restored tellurate sensitivity and uptake. These results indicate that tellurate enters E. coli cells to cause toxic effects via the CysPUWA sulfate transporter.
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45
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Cai JY, Wang YY, Ma K, Hou YN, Yao GD, Hayashi T, Itoh K, Tashiro SI, Onodera S, Ikejima T. Salicylate induces reactive oxygen species and reduces ultraviolet C susceptibility in Staphylococcus aureus. FEMS Microbiol Lett 2018; 365:4931717. [PMID: 29546276 DOI: 10.1093/femsle/fny056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 03/06/2018] [Indexed: 11/13/2022] Open
Abstract
This study demonstrates that growth of Staphylococcus aureus in the presence of salicylate reduces ultraviolet C (UVC)-induced cell death and increases the generation of reactive oxygen species (ROS). In addition, compounds that scavenge ROS (N-acetylcysteine, glutathione, catalase and superoxide dismutase) reverse the increased UVC survival induced by growth in the presence of salicylate, while ROS donors (tert-butylhydroperoxide, H2O2 and NaClO) enhance survival of salicylate challenged cultures. Collectively, these findings suggest that ROS production induced by growth in the presence of salicylate protects S. aureus from UVC-induced cell death.
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Affiliation(s)
- Jia-Yi Cai
- China-Japan Research Institute of Medical and Pharmaceutical Sciences, Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Yuan-Yuan Wang
- China-Japan Research Institute of Medical and Pharmaceutical Sciences, Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, China.,Department of Drug Discover and Development, Shanghai FrontHealth Pharmaceutical Technology Company, Shanghai 201203, China
| | - Kai Ma
- China-Japan Research Institute of Medical and Pharmaceutical Sciences, Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Yong-Na Hou
- China-Japan Research Institute of Medical and Pharmaceutical Sciences, Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Guo-Dong Yao
- School of Traditional Chinese Materia Medica, Key Laboratory of Structure-Based Drug Design & Discovery (Ministry of Education), Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Toshihiko Hayashi
- China-Japan Research Institute of Medical and Pharmaceutical Sciences, Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Kikuji Itoh
- Biochemical Center, Japan SLC, Inc., Shizuoka 431-1103, Japan
| | - Shin-Ichi Tashiro
- Department of Medical Education & Primary Care, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Satoshi Onodera
- Department of Clinical and Pharmaceutical Sciences, Showa Pharmaceutical University, Tokyo 194-8543, Japan
| | - Takashi Ikejima
- China-Japan Research Institute of Medical and Pharmaceutical Sciences, Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, China
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46
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Abo Elsoud MM, Al-Hagar OEA, Abdelkhalek ES, Sidkey NM. Synthesis and investigations on tellurium myconanoparticles. ACTA ACUST UNITED AC 2018; 18:e00247. [PMID: 29876299 PMCID: PMC5989594 DOI: 10.1016/j.btre.2018.e00247] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 02/22/2018] [Accepted: 03/07/2018] [Indexed: 01/24/2023]
Abstract
Tellurium has attracted the attention of many researchers and manufacturers due to its unique properties. Through the current work, six fungal isolates have been screened for their ability to reduce potassium tellurite (K2TeO3) into elemental tellurium nanoparticles (TeNPs). The most promising fungal isolate was identified as Aspergillus welwitschiae and given the accession number (KY766958) based on molecular basis and has been used for biogenic (enzymatic) production of TeNPs. The produced TeNPs have been characterized using DLS, TEM and FTIR. Data showed that, the particle size is 60.80 d.nm with oval to spherical shape. The produced TeNPs have been evaluated for antimicrobial activity at 25 mg/ml. Data revealed antibacterial activity against E. coli and Staphylococcus aureus (MRSA). Evaluation of the effect of γ-irradiation on TeNPs production showed that, the productivity was improved at 1 kGy and suppressed gradually at higher doses.
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Affiliation(s)
| | - Ola E A Al-Hagar
- Plant Research Dept., Nuclear Research Center, Atomic Energy Authority, Inshas, Egypt
| | - Eman S Abdelkhalek
- Department of Botany and Microbiology, Faculty of Science, Al Azhar University (Girls Branch), Cairo, Egypt
| | - N M Sidkey
- Department of Botany and Microbiology, Faculty of Science, Al Azhar University (Girls Branch), Cairo, Egypt
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47
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Muñoz-Villagrán CM, Mendez KN, Cornejo F, Figueroa M, Undabarrena A, Morales EH, Arenas-Salinas M, Arenas FA, Castro-Nallar E, Vásquez CC. Comparative genomic analysis of a new tellurite-resistant Psychrobacter strain isolated from the Antarctic Peninsula. PeerJ 2018; 6:e4402. [PMID: 29479501 PMCID: PMC5822837 DOI: 10.7717/peerj.4402] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 02/01/2018] [Indexed: 01/05/2023] Open
Abstract
The Psychrobacter genus is a cosmopolitan and diverse group of aerobic, cold-adapted, Gram-negative bacteria exhibiting biotechnological potential for low-temperature applications including bioremediation. Here, we present the draft genome sequence of a bacterium from the Psychrobacter genus isolated from a sediment sample from King George Island, Antarctica (3,490,622 bp; 18 scaffolds; G + C = 42.76%). Using phylogenetic analysis, biochemical properties and scanning electron microscopy the bacterium was identified as Psychrobacter glacincola BNF20, making it the first genome sequence reported for this species. P. glacincola BNF20 showed high tellurite (MIC 2.3 mM) and chromate (MIC 6.0 mM) resistance, respectively. Genome-wide nucleotide identity comparisons revealed that P. glacincola BNF20 is highly similar (>90%) to other uncharacterized Psychrobacter spp. such as JCM18903, JCM18902, and P11F6. Bayesian multi-locus phylogenetic analysis showed that P. glacincola BNF20 belongs to a polyphyletic clade with other bacteria isolated from polar regions. A high number of genes related to metal(loid) resistance were found, including tellurite resistance genetic determinants located in two contigs: Contig LIQB01000002.1 exhibited five ter genes, each showing putative promoter sequences (terACDEZ), whereas contig LIQB1000003.2 showed a variant of the terZ gene. Finally, investigating the presence and taxonomic distribution of ter genes in the NCBI’s RefSeq bacterial database (5,398 genomes, as January 2017), revealed that 2,623 (48.59%) genomes showed at least one ter gene. At the family level, most (68.7%) genomes harbored one ter gene and 15.6% exhibited five (including P. glacincola BNF20). Overall, our results highlight the diverse nature (genetic and geographic diversity) of the Psychrobacter genus, provide insights into potential mechanisms of metal resistance, and exemplify the benefits of sampling remote locations for prospecting new molecular determinants.
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Affiliation(s)
- Claudia Melissa Muñoz-Villagrán
- Laboratorio de Microbiología Molecular, Departamento de Biología, Universidad de Santiago de Chile, Santiago, Chile.,Departamento de Ciencias Básicas, Facultad de Ciencia, Universidad Santo Tomas Sede Santiago, Santiago, Chile
| | - Katterinne N Mendez
- Center for Bioinformatics and Integrative Biology, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Fabian Cornejo
- Laboratorio de Microbiología Molecular, Departamento de Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Maximiliano Figueroa
- Laboratorio de Microbiología Molecular, Departamento de Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Agustina Undabarrena
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química & Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Eduardo Hugo Morales
- Laboratorio de Microbiología Molecular, Departamento de Biología, Universidad de Santiago de Chile, Santiago, Chile
| | | | - Felipe Alejandro Arenas
- Laboratorio de Microbiología Molecular, Departamento de Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Eduardo Castro-Nallar
- Center for Bioinformatics and Integrative Biology, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Claudio Christian Vásquez
- Laboratorio de Microbiología Molecular, Departamento de Biología, Universidad de Santiago de Chile, Santiago, Chile
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48
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Shakibaie M, Adeli-Sardou M, Mohammadi-Khorsand T, ZeydabadiNejad M, Amirafzali E, Amirpour-Rostami S, Ameri A, Forootanfar H. Antimicrobial and Antioxidant Activity of the Biologically Synthesized Tellurium Nanorods; A Preliminary In vitro Study. IRANIAN JOURNAL OF BIOTECHNOLOGY 2017; 15:268-276. [PMID: 29845079 DOI: 10.15171/ijb.1580] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Revised: 02/27/2017] [Accepted: 10/08/2017] [Indexed: 01/23/2023]
Abstract
Background: Recent theranostic (therapeutic or diagnostic) applications of tellurium nanoparticles have attracted a great interest for development of different methods for synthesis of this valuable nanostructure, especially via biological resources. Objectives: In the present study, the antimicrobial and antioxidant effects of the tellurium nanorods (Te NRs) biosynthesized by a bacterial strain Pseudomonas pseudoalcaligenes strain Te were evaluated. Materials and Methods: The antimicrobial effect of Te NRs and potassium tellurite against different bacterial and fungal pathogens was assessed by microdilution method. Furthermore, the disk diffusion method was used to evaluate the antibacterial effect of the biogenic Te NRs and potassium tellurite against methicillin-resistant Staphylococcus aureus, alone or in combination with various antibiotics. Also, the biogenic Te NRs were investigated for antioxidant activity using 2, 2-diphenyl- 1-picrylhydrazyl (DPPH) scavenging activity and reducing power assay. Results: Transmission electron micrograph (TEM) of the purified Te NRs showed individual and rod-shaped nanostructure (~22 nm diameter by 185 nm in length). Based on the data obtained from both microdilution and disk diffusion method the K2 TeO3 exhibited a higher antibacterial and antifungal activity compared to the Te NRs. The measured IC50 for the biogenic Te NRs (i.e. DPPH radical scavenging activity) was found to be 24.9 μg.mL-1, while, K 2 TeO3 has represented only 17.6 ± 0.8 % DPPH radical scavenging effect at the concentration of 160 μg.mL-1. The reducing power assay revealed a higher electron-donating activity for Te NRs compared to K2TeO3. Conclusions: Based on the data obtained from both microdilution and disk diffusion method the K2TeO3 exhibited a higher antimicrobial and antifungal activity than Te NRs. Te NRs didn't show the antibacterial effect against the tested bacterial strain: MRSA and showed an inhibitory effect and antibacterial activity of the effective antibiotics. However, more studies should be performed to explore the action mechanism of the produced biogenic Te NRs.
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Affiliation(s)
- Mojtaba Shakibaie
- Herbal and Traditional Medicines Research Center, Kerman University of Medical Sciences, Kerman, Iran.,Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Mahboubeh Adeli-Sardou
- Herbal and Traditional Medicines Research Center, Kerman University of Medical Sciences, Kerman, Iran
| | - Tayebe Mohammadi-Khorsand
- Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Mahdie ZeydabadiNejad
- The Student Research Committee, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran
| | - Ehsan Amirafzali
- The Student Research Committee, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran
| | - Sahar Amirpour-Rostami
- Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Atefeh Ameri
- Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Hamid Forootanfar
- Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran.,Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran
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49
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Valdivia-González MA, Díaz-Vásquez WA, Ruiz-León D, Becerra AA, Aguayo DR, Pérez-Donoso JM, Vásquez CC. A comparative analysis of tellurite detoxification by members of the genus Shewanella. Arch Microbiol 2017; 200:267-273. [PMID: 29022087 DOI: 10.1007/s00203-017-1438-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 09/25/2017] [Accepted: 10/05/2017] [Indexed: 10/18/2022]
Abstract
The increasing industrial utilization of tellurium has resulted in an important environmental pollution with the soluble, extremely toxic oxyanion tellurite. In this context, the use of microorganisms for detoxifying tellurite or tellurium biorecovery has gained great interest. The ability of different Shewanella strains to reduce tellurite to elemental tellurium was assessed; the results showed that the reduction process is dependent on electron transport and the ∆pH gradient. While S. baltica OS155 showed the highest tellurite resistance, S. putrefaciens was the most efficient in reducing tellurite. Moreover, pH-dependent tellurite transformation was associated with tellurium precipitation as tellurium dioxide. In summary, this work highlights the high tellurite reduction/detoxification ability exhibited by a number of Shewanella species, which could represent the starting point to develop friendly methods for the recovery of elemental tellurium (or tellurium dioxide).
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Affiliation(s)
- M A Valdivia-González
- Laboratorio de Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Avenida Libertador Bernardo O'Higgins #3363. Estación Central, Santiago, Chile.,Facultad de Ciencias de la Educación, Universidad Central de Chile, Santiago, Chile
| | - W A Díaz-Vásquez
- Facultad de Ciencias de la Salud, Universidad San Sebastián, Providencia, Chile
| | - D Ruiz-León
- Departamento de Química de los Materiales, Universidad de Santiago de Chile, Santiago, Chile
| | - A A Becerra
- Facultad de Salud, Deporte y Recreación, Universidad Bernardo O'Higgins, Santiago, Chile
| | - D R Aguayo
- Molecular Biophysics and Bionformatics Group, Universidad Andrés Bello, Santiago, Chile
| | - J M Pérez-Donoso
- BioNanotechnology and Microbiology Laboratory, Universidad Andrés Bello, Santiago, Chile
| | - C C Vásquez
- Laboratorio de Microbiología Molecular, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Avenida Libertador Bernardo O'Higgins #3363. Estación Central, Santiago, Chile.
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50
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Bhattaram V, Upadhyay A, Yin HB, Mooyottu S, Venkitanarayanan K. Effect of Dietary Minerals on Virulence Attributes of Vibrio cholerae. Front Microbiol 2017; 8:911. [PMID: 28579983 PMCID: PMC5437166 DOI: 10.3389/fmicb.2017.00911] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Accepted: 05/04/2017] [Indexed: 12/22/2022] Open
Abstract
Vibrio cholerae is a water-borne pathogen responsible for causing a toxin-mediated profuse diarrhea in humans, leading to severe dehydration and death in unattended patients. With increasing reports of antibiotic resistance in V. cholerae, there is a need for alternate interventional strategies for controlling cholera. A potential new strategy for treating infectious diseases involves targeting bacterial virulence rather than growth, where a pathogen’s specific mechanisms critical for causing infection in hosts are inhibited. Since bacterial motility, intestinal colonization and cholera toxin are critical components in V. cholerae pathogenesis, attenuating these virulence factors could potentially control cholera in humans. In this study, the efficacy of sub-inhibitory concentration (SIC, highest concentration not inhibiting bacterial growth) of essential minerals, zinc (Zn), selenium (Se), and manganese (Mn) in reducing V. cholerae motility and adhesion to intestinal epithelial cells (Caco-2), cholera toxin production, and toxin binding to the ganglioside receptor (GM1) was investigated. Additionally, V. cholerae attachment and toxin production in an ex vivo mouse intestine model was determined. Further, the effect of Zn, Se and Mn on V. cholerae virulence genes, ctxAB (toxin production), fliA (motility), tcpA (intestinal colonization), and toxR (master regulon) was determined using real-time quantitative PCR. All three minerals significantly reduced V. cholerae motility, adhesion to Caco-2 cells, and cholera toxin production in vitro, and decreased adhesion and toxin production in mouse intestine ex vivo (P < 0.05). In addition, Zn, Se, and Mn down-regulated the transcription of virulence genes, ctxAB, fliA, and toxR. Results suggest that Zn, Se, and Mn could be potentially used to reduce V. cholerae virulence. However, in vivo studies in an animal model are necessary to validate these results.
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Affiliation(s)
- Varunkumar Bhattaram
- Department of Animal Science, University of Connecticut, StorrsCT, United States
| | - Abhinav Upadhyay
- Department of Animal Science, University of Connecticut, StorrsCT, United States.,Department of Poultry Science, University of Arkansas, FayettevilleAR, United States
| | - Hsin-Bai Yin
- Department of Animal Science, University of Connecticut, StorrsCT, United States
| | - Shankumar Mooyottu
- Department of Animal Science, University of Connecticut, StorrsCT, United States
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