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Marks TJ, Rowland IR. The Diversity of Bacteriophages in Hot Springs. Methods Mol Biol 2024; 2738:73-88. [PMID: 37966592 DOI: 10.1007/978-1-0716-3549-0_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
Bacteriophages are ubiquitous in all environments that support microbial life. This includes hot springs, which can range in temperatures between 40 and 98 °C and pH levels between 1 and 9. Bacteriophages that survive in the higher temperatures of hot springs are known as thermophages. Thermophages have developed distinct adaptations allowing for thermostability in these extreme environments, including increased G + C DNA percentages, reliance upon the pentose phosphate metabolic pathway to avoid oxidative stress, and a codon preference for those with a GNA sequence leading to increased hydrophobic interactions and disulfide bonds. In this review, we discuss the diversity of characterized thermophages in hot spring environments that span five viral families: Myoviridae, Siphoviridae, Tectiviridae, Sphaerolipoviridae, and Inoviridae. Potential industrial and medicinal applications of thermophages will also be addressed.
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Affiliation(s)
- Timothy J Marks
- Department of Pharmaceutical and Clinical Sciences, Campbell University, Buies Creek, NC, USA.
| | - Isabella R Rowland
- Department of Pharmaceutical and Clinical Sciences, Campbell University, Buies Creek, NC, USA
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2
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Zhen ZG, Luo JX, Su Y, Xia ZY, An T, Sun ZY, Gou M, Tang YQ. Different responses of mesophilic and thermophilic anaerobic digestion of waste activated sludge to PVC microplastics. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:121584-121598. [PMID: 37957495 DOI: 10.1007/s11356-023-30935-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 11/02/2023] [Indexed: 11/15/2023]
Abstract
The effect of microplastics (MPs) retained in waste activated sludge (WAS) on anaerobic digestion (AD) performance has attracted more and more attention. However, their effect on thermophilic AD remains unclear. Here, the influence of polyvinyl chloride (PVC) MPs on methanogenesis and active microbial communities in mesophilic (37 °C) and thermophilic (55 °C) AD was investigated. The results showed that 1, 5, and 10 mg/L PVC MPs significantly promoted the cumulative methane yield in mesophilic AD by 5.62%, 7.36%, and 8.87%, respectively, while PVC MPs reduced that in thermophilic AD by 13.30%, 18.82%, and 19.99%, respectively. Moreover, propionate accumulation was only detected at the end of thermophilic AD with PVC MPs. Microbial community analysis indicated that PVC MPs in mesophilic AD enriched hydrolytic and acidifying bacteria (Candidatus Competibacter, Lentimicrobium, Romboutsia, etc.) together with acetoclastic methanogens (Methanosarcina, Methanosaeta). By contrast, most carbohydrate-hydrolyzing bacteria, propionate-oxidizing bacterium (Pelotomaculum), and Methanosarcina were inhibited by PVC MPs in thermophilic AD. Network analysis further suggested that PVC MPs significantly changed the relationship of key microorganisms in the AD process. A stronger correlation among the above genera occurred in mesophilic AD, which may promote the methanogenic performance. These results suggested that PVC MPs affected mesophilic and thermophilic AD of WAS via changing microbial activities and interaction.
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Affiliation(s)
- Zhao-Gan Zhen
- College of Architecture and Environment, Sichuan University, No. 24 South Section 1 First Ring Road, Chengdu, 610065, Sichuan Province, China
| | - Jun-Xiao Luo
- College of Architecture and Environment, Sichuan University, No. 24 South Section 1 First Ring Road, Chengdu, 610065, Sichuan Province, China
| | - Yang Su
- College of Architecture and Environment, Sichuan University, No. 24 South Section 1 First Ring Road, Chengdu, 610065, Sichuan Province, China
| | - Zi-Yuan Xia
- College of Architecture and Environment, Sichuan University, No. 24 South Section 1 First Ring Road, Chengdu, 610065, Sichuan Province, China
| | - Tong An
- College of Architecture and Environment, Sichuan University, No. 24 South Section 1 First Ring Road, Chengdu, 610065, Sichuan Province, China
| | - Zhao-Yong Sun
- College of Architecture and Environment, Sichuan University, No. 24 South Section 1 First Ring Road, Chengdu, 610065, Sichuan Province, China
| | - Min Gou
- College of Architecture and Environment, Sichuan University, No. 24 South Section 1 First Ring Road, Chengdu, 610065, Sichuan Province, China.
| | - Yue-Qin Tang
- College of Architecture and Environment, Sichuan University, No. 24 South Section 1 First Ring Road, Chengdu, 610065, Sichuan Province, China
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Nair IM, Kochupurackal J. Squalene hopene cyclases and oxido squalene cyclases: potential targets for regulating cyclisation reactions. Biotechnol Lett 2023; 45:573-588. [PMID: 37055654 DOI: 10.1007/s10529-023-03366-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 03/01/2023] [Accepted: 03/14/2023] [Indexed: 04/15/2023]
Abstract
Squalene hopene cyclases (SHC) convert squalene, the linear triterpene to fused ring product hopanoid by the cationic cyclization mechanism. The main function of hopanoids, a class of pentacyclic triterpenoids in bacteria involves the maintenance of membrane fluidity and stability. 2, 3-oxido squalene cyclases are functional analogues of SHC in eukaryotes and both these enzymes have fascinated researchers for the high stereo selectivity, complexity, and efficiency they possess. The peculiar property of the enzyme squalene hopene cyclase to accommodate substrates other than its natural substrate can be exploited for the use of these enzymes in an industrial perspective. Here, we present an extensive overview of the enzyme squalene hopene cyclase with emphasis on the cloning and overexpression strategies. An attempt has been made to explore recent research trends around squalene cyclase mediated cyclization reactions of flavour and pharmaceutical significance by using non-natural molecules as substrates.
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Affiliation(s)
- Indu Muraleedharan Nair
- School of Biosciences, Mahatma Gandhi University, Athirampuzha, Kottayam, 686560, India
- Department of Physiology, School of Medicine, University College Cork, Cork, T12 XF62, Ireland
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Ren X, Whitton MM, Yu SJ, Trotter T, Bajagai YS, Stanley D. Application of Phytogenic Liquid Supplementation in Soil Microbiome Restoration in Queensland Pasture Dieback. Microorganisms 2023; 11:microorganisms11030561. [PMID: 36985135 PMCID: PMC10054416 DOI: 10.3390/microorganisms11030561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 02/20/2023] [Accepted: 02/20/2023] [Indexed: 02/25/2023] Open
Abstract
Pasture production is vital in cattle farming as it provides animals with food and nutrients. Australia, as a significant global beef producer, has been experiencing pasture dieback, a syndrome of deteriorating grassland that results in the loss of grass and the expansion of weeds. Despite two decades of research and many remediation attempts, there has yet to be a breakthrough in understanding the causes or mechanisms involved. Suggested causes of this phenomenon include soil and plant microbial pathogens, insect infestation, extreme heat stress, radiation, and others. Plants produce a range of phytomolecules with antifungal, antibacterial, antiviral, growth-promoting, and immunostimulant effects to protect themselves from a range of environmental stresses. These products are currently used more in human and veterinary health than in agronomy. In this study, we applied a phytogenic product containing citric acid, carvacrol, and cinnamaldehyde, to investigate its ability to alleviate pasture dieback. The phytogenic liquid-based solution was sprayed twice, one week apart, at 5.4 L per hectare. The soil microbial community was investigated longitudinally to determine long-term effects, and pasture productivity and plant morphometric improvements were explored. The phytogenic liquid significantly improved post-drought recovery of alpha diversity and altered temporal and spatial change in the community. The phytogenic liquid reduced biomarker genera associated with poor and polluted soils and significantly promoted plant and soil beneficial bacteria associated with plant rhizosphere and a range of soil benefits. Phytogenic liquid application produced plant morphology improvements and a consistent enhancement of pasture productivity extending beyond 18 months post-application. Our data show that phytogenic products used in the livestock market as an alternative to antibiotics may also have a beneficial role in agriculture, especially in the light of climate change-related soil maintenance and remediation.
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Morvan S, Paré MC, Schmitt A, Lafond J, Hijri M. Limited effect of thermal pruning on wild blueberry crop and its root-associated microbiota. FRONTIERS IN PLANT SCIENCE 2022; 13:954935. [PMID: 36035689 PMCID: PMC9408806 DOI: 10.3389/fpls.2022.954935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 07/01/2022] [Indexed: 06/15/2023]
Abstract
Thermal pruning was a common pruning method in the past but has progressively been replaced by mechanical pruning for economic reasons. Both practices are known to enhance and maintain high yields; however, thermal pruning was documented to have an additional sanitation effect by reducing weeds and fungal diseases outbreaks. Nevertheless, there is no clear consensus on the optimal fire intensity required to observe these outcomes. Furthermore, fire is known to alter the soil microbiome as it impacts the soil organic layer and chemistry. Thus far, no study has investigated into the effect of thermal pruning intensity on the wild blueberry microbiome in agricultural settings. This project aimed to document the effects of four gradual thermal pruning intensities on the wild blueberry performance, weeds, diseases, as well as the rhizosphere fungal and bacterial communities. A field trial was conducted using a block design where agronomic variables were documented throughout the 2-year growing period. MiSeq amplicon sequencing was used to determine the diversity as well as the structure of the bacterial and fungal communities. Overall, yield, fruit ripeness, and several other agronomical variables were not significantly impacted by the burning treatments. Soil phosphorus was the only parameter with a significant albeit temporary change (1 month after thermal pruning) for soil chemistry. Our results also showed that bacterial and fungal communities did not significantly change between burning treatments. The fungal community was dominated by ericoid mycorrhizal fungi, while the bacterial community was mainly composed of Acidobacteriales, Isosphaerales, Frankiales, and Rhizobiales. However, burning at high intensities temporarily reduced Septoria leaf spot disease in the season following thermal pruning. According to our study, thermal pruning has a limited short-term influence on the wild blueberry ecosystem but may have a potential impact on pests (notably Septoria infection), which should be explored in future studies to determine the burning frequency necessary to control this disease.
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Affiliation(s)
- Simon Morvan
- Institut de Recherche en Biologie Vègétale, Département de sciences biologiques, Université de Montréal, Montréal, QC, Canada
| | - Maxime C. Paré
- Laboratoire sur les écosystèmes boréaux terrestres (EcoTer), Département des Sciences Fondamentales, Université du Québec à Chicoutimi, Chicoutimi, QC, Canada
| | - Anne Schmitt
- Laboratoire sur les écosystèmes boréaux terrestres (EcoTer), Département des Sciences Fondamentales, Université du Québec à Chicoutimi, Chicoutimi, QC, Canada
| | - Jean Lafond
- Direction générale des sciences et de la technologie, Agriculture et Agroalimentaire Canada, Gouvernement du Canada, Normandin, QC, Canada
| | - Mohamed Hijri
- Institut de Recherche en Biologie Vègétale, Département de sciences biologiques, Université de Montréal, Montréal, QC, Canada
- African Genome Center, Mohammed VI Polytechnic University, Ben Guerir, Morocco
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6
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Salwan R, Sharma V. Genomics of Prokaryotic Extremophiles to Unfold the Mystery of Survival in Extreme Environments. Microbiol Res 2022; 264:127156. [DOI: 10.1016/j.micres.2022.127156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 07/30/2022] [Accepted: 07/31/2022] [Indexed: 11/26/2022]
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Liu Q, Wu H, Huang C, Lin H, Li W, Zhao X, Li Z, Lv S. Microbial compositions, ecological networks, and metabolomics in sediments of black-odour water in Dongguan, China. ENVIRONMENTAL RESEARCH 2022; 210:112918. [PMID: 35181306 DOI: 10.1016/j.envres.2022.112918] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 01/29/2022] [Accepted: 02/06/2022] [Indexed: 06/14/2023]
Abstract
Black-odour water with organic compounds and heavy metals caused by domestic and industrial activities has aroused people's attention in recent years, yet little is known about the ecological effects on aquatic organisms, especially microorganisms in sediments. To explore the response of microbial communities to environmental factors, the community and metabolites of nine river sediments with different pollution in Dongguan city, China were investigated using 16S rRNA gene sequencing and liquid chromatography tandem-mass. The results revealed that the composition and structure of sedimentary microbial communities significantly changed in rivers with varying pollution levels. Cyanobacteria were the most abundant organisms in the sediment of black-odorous rivers, while the relative abundance of Thaumarchaeota was gradually increased with the river quality gets better. The relative abundance of organic acids (including amino acids), alcohols, esters, and ketones associated with microbial metabolism in sediments of polluted rivers was increased. The 16S rRNA gene sequencing-based molecular ecological network analysis indicated that the interactions amongst bacteria were enhanced in severely contaminated communities. Sphingomonadaceae and Cyanobacteria have important roles in bacterial community structures of polluted rivers and those with ongoing treatment. The correlation analysis showed significant metal resistance and/or tolerance of the following bacteria species Thalassiosira weissflogii, Aminicenantes bacterium clone OPB95, 'Candidatus Halomonas phosphatis', and archaeal species Methanolinea and unidentified Thermoplasmata. These results indicated that sedimentary microbial communities may shift in composition and structure, as well as their interaction network, to adapt and resist environmental contamination and promote restoration.
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Affiliation(s)
- Qian Liu
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan, 523808, China
| | - Haowen Wu
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan, 523808, China
| | - Cong Huang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China; National Technology Innovation Center of Synthetic Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
| | - Hui Lin
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan, 523808, China
| | - Wei Li
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan, 523808, China
| | - XiuFang Zhao
- Ecological Science Institute, LingNan Eco & Culture-Tourism Co.Ltd., Dongguan, 523125, China
| | - Zhiling Li
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Sihao Lv
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan, 523808, China.
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8
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Changes in Bacterial Diversity and Composition in Response to Co-inoculation of Arbuscular Mycorrhizae and Zinc-Solubilizing Bacteria in Turmeric Rhizosphere. Curr Microbiol 2021; 79:4. [PMID: 34894281 DOI: 10.1007/s00284-021-02682-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 10/02/2021] [Indexed: 10/19/2022]
Abstract
In the present study, the impact of co-inoculation of arbuscular mycorrhizal fungi (AM Rhizophagus sp., NCBI-MN710507) and Zinc solubilizing bacteria (ZSB2- Bacillus megaterium, NCBI-KY687496) on plant growth, soil dehydrogenase activity, soil respiration and the changes in bacterial diversity in rhizosphere of turmeric (Curcuma longa) were examined. Our results showed that higher plant height and dry biomass were observed in treatments co-inoculated with AM and ZSB2. Likewise, dehydrogenase activity and soil respiration were more significant in the co-inoculation treatment, indicating abundance of introduced as well as inherent microflora. Bacterial community analysis using 16S rRNA revealed changes in the structure and diversity of various taxa due to co-inoculation of AM and ZSB2. Alpha diversity indexes (Shannon and Chao1) and beta diversity indexes obtained through unweighted unifrac approach also showed variation among the treated samples. Chloroflexi was the dominant phylum followed by Proteobacteria, Actinobacteria and Acidobacteria which accounted for 80% of all treated samples. The composition of bacterial communities at genus level revealed that co-inoculation caused distinct bacterial profiles. The Linear discriminant analysis effect size revealed the dominance of ecologically significant genera such as Bradyrhizobium, Candidatus, Pedomicrbium, Thermoporothrix, Acinetobacter and Nitrospira in treatments co-inoculated with AM and ZSB2. On the whole, co-inoculated treatments revealed enhanced microbial activities and caused significant positive shifts in the bacterial diversity and abundance compared to treatments with sole application of ZSB2 or AM.
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9
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Broadbent AAD, Bahn M, Pritchard WJ, Newbold LK, Goodall T, Guinta A, Snell HSK, Cordero I, Michas A, Grant HK, Soto DX, Kaufmann R, Schloter M, Griffiths RI, Bardgett RD. Shrub expansion modulates belowground impacts of changing snow conditions in alpine grasslands. Ecol Lett 2021; 25:52-64. [PMID: 34708508 DOI: 10.1111/ele.13903] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/18/2021] [Accepted: 10/06/2021] [Indexed: 11/28/2022]
Abstract
Climate change is disproportionately impacting mountain ecosystems, leading to large reductions in winter snow cover, earlier spring snowmelt and widespread shrub expansion into alpine grasslands. Yet, the combined effects of shrub expansion and changing snow conditions on abiotic and biotic soil properties remains poorly understood. We used complementary field experiments to show that reduced snow cover and earlier snowmelt have effects on soil microbial communities and functioning that persist into summer. However, ericaceous shrub expansion modulates a number of these impacts and has stronger belowground effects than changing snow conditions. Ericaceous shrub expansion did not alter snow depth or snowmelt timing but did increase the abundance of ericoid mycorrhizal fungi and oligotrophic bacteria, which was linked to decreased soil respiration and nitrogen availability. Our findings suggest that changing winter snow conditions have cross-seasonal impacts on soil properties, but shifts in vegetation can modulate belowground effects of future alpine climate change.
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Affiliation(s)
- Arthur A D Broadbent
- Department of Earth and Environmental Sciences, The University of Manchester, Manchester, UK
| | - Michael Bahn
- Institut für Ökologie, Universität Innsbruck, Innsbruck, Austria
| | - William J Pritchard
- Department of Earth and Environmental Sciences, The University of Manchester, Manchester, UK
| | | | - Tim Goodall
- UK Centre for Ecology & Hydrology, Wallingford, Oxfordshire, UK
| | - Andrew Guinta
- Institut für Ökologie, Universität Innsbruck, Innsbruck, Austria
| | - Helen S K Snell
- Department of Earth and Environmental Sciences, The University of Manchester, Manchester, UK
| | - Irene Cordero
- Department of Earth and Environmental Sciences, The University of Manchester, Manchester, UK
| | - Antonios Michas
- Research Unit for Comparative Microbiome Analysis, Helmholtz Zentrum München, Neuherberg, Germany.,Chair for Soil Science, Technical University of Munich, Freising, Germany
| | - Helen K Grant
- National Environmental Isotope Facility, UK Centre for Ecology & Hydrology, Lancaster Environment Centre, Lancaster, UK
| | - David X Soto
- National Environmental Isotope Facility, UK Centre for Ecology & Hydrology, Lancaster Environment Centre, Lancaster, UK
| | - Rüdiger Kaufmann
- Institut für Ökologie, Universität Innsbruck, Innsbruck, Austria
| | - Michael Schloter
- Research Unit for Comparative Microbiome Analysis, Helmholtz Zentrum München, Neuherberg, Germany.,Chair for Soil Science, Technical University of Munich, Freising, Germany
| | - Robert I Griffiths
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Gwynedd, UK
| | - Richard D Bardgett
- Department of Earth and Environmental Sciences, The University of Manchester, Manchester, UK
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Huang R, Zhang F, Yan X, Qin Y, Jiang J, Liu Y, Song Y. Characterization of the β-Glucosidase activity in indigenous yeast isolated from wine regions in China. J Food Sci 2021; 86:2327-2345. [PMID: 33929752 DOI: 10.1111/1750-3841.15741] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 03/15/2021] [Accepted: 03/28/2021] [Indexed: 11/25/2022]
Abstract
β-glucosidase is a pivotal enzyme that hydrolyzes bound volatile aromatic compounds. However, the activity of β-glucosidase in winemaking and the mechanism by which it affects the flavor and taste of wines have not been fully investigated. In this study, we profiled the characteristics of β-glucosidase derived from wine-related yeasts isolated from different wine-making regions in China, and analyzed the enzyme activity from different parts of the cells under aerobic and anaerobic conditions. A total of 56 strains of wine-related yeasts producing β-glucosidases were screened using the YNB-C medium (YNB 6.7 g L-1 , cellobiose 5 g L-1 , pH 5.0). We found that strain Clavispora lusitaniae C117 produced the highest enzyme activity (152.39 µmol pNP ml-1 h-1 ). In most strains, β-glucosidase were located in whole cells (periplasmic space) and permeabilized cells (intracellular). The non-Saccharomyces species had the highest enzymatic activity in a strain-dependent manner. Under aerobic conditions, C. lusitaniae C117, Hanseniaspora guilliermondii A27-3-4, Metschnikowia pulcherrima F-1-6, and Pichia anomala C84 had the highest β-glucosidase activity. We further investigated the β-glucosidase activity during the wine fermentation and the effects of sugar, pH, temperature, and ethanol on the enzyme activities of P. anomala C84 and commercial Saccharomyces yeast strains RC212 and VL1. The presence of fructose, glucose, and sucrose strongly inhibited enzyme activity. Similarly, low pH and low temperature inhibited the activity of β-glucosidase, whereas ethanol promoted enzyme activity. Our findings provide a theoretical basis on understanding the different yeast characteristics of β-glucosidase and their potential application for further improving wine aroma complexity.
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Affiliation(s)
- Rong Huang
- College of Enology, Northwest A&F University, Yangling, Shaanxi, China
| | - Fangfang Zhang
- College of Enology, Northwest A&F University, Yangling, Shaanxi, China
| | - Xingmin Yan
- College of Enology, Northwest A&F University, Yangling, Shaanxi, China
| | - Yi Qin
- College of Enology, Northwest A&F University, Yangling, Shaanxi, China
| | - Jiao Jiang
- College of Enology, Northwest A&F University, Yangling, Shaanxi, China
| | - Yanlin Liu
- College of Enology, Northwest A&F University, Yangling, Shaanxi, China.,Shaanxi Engineering Research Center for Viti-Viniculture, Yangling, Shaanxi, China
| | - Yuyang Song
- College of Enology, Northwest A&F University, Yangling, Shaanxi, China.,Shaanxi Engineering Research Center for Viti-Viniculture, Yangling, Shaanxi, China
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Viotti C, Bach C, Maillard F, Ziegler-Devin I, Mieszkin S, Buée M. Sapwood and heartwood affect differentially bacterial and fungal community structure and successional dynamics during Quercus petraea decomposition. Environ Microbiol 2021; 23:6177-6193. [PMID: 33848050 DOI: 10.1111/1462-2920.15522] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 04/07/2021] [Accepted: 04/08/2021] [Indexed: 11/28/2022]
Abstract
In forests, bacteria and fungi are key players in wood degradation. Still, studies focusing on bacterial and fungal successions during the decomposition process depending on the wood types (i.e. sapwood and heartwood) remain scarce. This study aimed to understand the effect of wood type on the dynamics of microbial ecological guilds in wood decomposition. Using Illumina metabarcoding, bacterial and fungal communities were monitored every 3 months for 3 years from Quercus petraea wood discs placed on forest soil. Wood density and microbial enzymes involved in biopolymer degradation were measured. We observed rapid changes in the bacterial and fungal communities and microbial ecological guilds associated with wood decomposition throughout the experiment. Bacterial and fungal succession dynamics were very contrasted between sapwood and heartwood. The initial microbial communities were quickly replaced by new bacterial and fungal assemblages in the sapwood. Conversely, some initial functional guilds (i.e. endophytes and yeasts) persisted all along the experiment in heartwood and finally became dominant, possibly limiting the development of saprotrophic fungi. Our data also suggested a significant role of bacteria in nitrogen cycle during wood decomposition.
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Affiliation(s)
- Chloé Viotti
- Université de Lorraine, INRAE, UMR IAM, Centre INRAE-Grand Est-Nancy, 54280 Champenoux, Nancy, F-54000, France
| | - Cyrille Bach
- Université de Lorraine, INRAE, UMR IAM, Centre INRAE-Grand Est-Nancy, 54280 Champenoux, Nancy, F-54000, France
| | - François Maillard
- Department of Plant and Microbial Biology University of Minnesota St. Paul, Saint Paul, Minnesota, 55108, USA
| | | | - Sophie Mieszkin
- Université de Lorraine, INRAE, UMR IAM, Centre INRAE-Grand Est-Nancy, 54280 Champenoux, Nancy, F-54000, France
| | - Marc Buée
- Université de Lorraine, INRAE, UMR IAM, Centre INRAE-Grand Est-Nancy, 54280 Champenoux, Nancy, F-54000, France
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12
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Soil Microbiome Composition along the Natural Norway Spruce Forest Life Cycle. FORESTS 2021. [DOI: 10.3390/f12040410] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Stand-replacing disturbances are a key element of the Norway spruce (Picea abies) forest life cycle. While the effect of a natural disturbance regime on forest physiognomy, spatial structure and pedocomplexity was well described in the literature, its impact on the microbiome, a crucial soil component that mediates nutrient cycling and stand productivity, remains largely unknown. For this purpose, we conducted research on a chronosequence of sites representing the post-disturbance development of a primeval Norway spruce forest in the Calimani Mts., Romania. The sites were selected along a gradient of duration from 16 to 160 years that ranges from ecosystem regeneration phases of recently disturbed open gaps to old-growth forest stands. Based on DNA amplicon sequencing, we followed bacterial and fungal community composition separately in organic, upper mineral and spodic horizons of present Podzol soils. We observed that the canopy opening and subsequent expansion of the grass-dominated understorey increased soil N availability and soil pH, which was reflected in enlarged bacterial abundance and diversity, namely due to the contribution of copiotrophic bacteria that prefer nutrient-richer conditions. The fungal community composition was affected by the disturbance as well but, contrary to our expectations, with no obvious effect on the relative abundance of ectomycorrhizal fungi. Once the mature stand was re-established, the N availability was reduced, the pH gradually decreased and the original old-growth forest microbial community dominated by acidotolerant oligotrophs recovered. The effect of the disturbance and forest regeneration was most evident in organic horizons, while the manifestation of these events was weaker and delayed in deeper soil horizons.
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Choma M, Tahovská K, Kaštovská E, Bárta J, Růžek M, Oulehle F. Bacteria but not fungi respond to soil acidification rapidly and consistently in both a spruce and beech forest. FEMS Microbiol Ecol 2021; 96:5894924. [PMID: 32815987 DOI: 10.1093/femsec/fiaa174] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 08/18/2020] [Indexed: 11/13/2022] Open
Abstract
Anthropogenically enhanced atmospheric sulphur (S) and nitrogen (N) deposition has acidified and eutrophied forest ecosystems worldwide. However, both S and N mechanisms have an impact on microbial communities and the consequences for microbially driven soil functioning differ. We conducted a two-forest stand (Norway spruce and European beech) field experiment involving acidification (sulphuric acid addition) and N (ammonium nitrate) loading and their combination. For 4 years, we monitored separate responses of soil microbial communities to the treatments and investigated the relationship to changes in the activity of extracellular enzymes. We observed that acidification selected for acidotolerant and oligotrophic taxa of Acidobacteria and Actinobacteria decreased bacterial community richness and diversity in both stands in parallel, disregarding their original dissimilarities in soil chemistry and composition of microbial communities. The shifts in bacterial community influenced the stoichiometry and magnitude of enzymatic activity. The bacterial response to experimental N addition was much weaker, likely due to historically enhanced N availability. Fungi were not influenced by any treatment during 4-year manipulation. We suggest that in the onset of acidification when fungi remain irresponsive, bacterial reaction might govern the changes in soil enzymatic activity.
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Affiliation(s)
- Michal Choma
- Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
| | - Karolina Tahovská
- Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
| | - Eva Kaštovská
- Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
| | - Jiří Bárta
- Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic
| | - Michal Růžek
- Czech Geological Survey, Department of Environmental Geochemistry and Biogeochemistry, Geologická 6, Prague 5, 152 00, Czech Republic.,Department of Physical Geography, Faculty of Science, Charles University, Albertov 6, 128 43 Prague, Czech Republic
| | - Filip Oulehle
- Czech Geological Survey, Department of Environmental Geochemistry and Biogeochemistry, Geologická 6, Prague 5, 152 00, Czech Republic
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14
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Tang X, Jiang J, Huang Z, Wu H, Wang J, He L, Xiong F, Zhong R, Liu J, Han Z, Tang R, He L. Sugarcane/peanut intercropping system improves the soil quality and increases the abundance of beneficial microbes. J Basic Microbiol 2021; 61:165-176. [PMID: 33448033 DOI: 10.1002/jobm.202000750] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 01/02/2021] [Indexed: 11/11/2022]
Abstract
Sugarcane/peanut intercropping is a highly efficient planting pattern in South China. However, the effects of sugarcane/peanut intercropping on soil quality need to be clarified. This study characterized the soil microbial community and the soil quality in sugarcane/peanut intercropping systems by the Illumina MiSeq platform. The results showed that the intercropping sugarcane (IS) system significantly increased the total N (TN), available N (AN), available P (AP), pH value, and acid phosphatase activity (ACP), but it had little effect on the total P (TP), total K (TK), available K (AK), organic matter (OM), urease activity, protease activity, catalase activity, and sucrase activity, compared with those in monocropping sugarcane (MS) and monocropping peanut (MP) systems. Both intercropping peanut (IP) and IS soils contained more bacteria and fungi than soils in the MP and MS fields, and the microbes identified were mainly Chloroflexi and Acidobacteria, respectively. Intercropping significantly increased the number of unique microbes in IS soils (68 genera), compared with the numbers in the IP (14), MS (17), and MP (16) systems. The redundancy analysis revealed that the abundances of culturable Acidobacteriaceae subgroup 1, nonculturable DA111, and culturable Acidobacteria were positively correlated with the measured soil quality in the intercropping system. Furthermore, the sugarcane/peanut intercropping significantly increased the economic benefit by 87.84% and 36.38%, as compared with that of the MP and MS, respectively. These results suggest that peanut and sugarcane intercropping increases the available N and P content by increasing the abundance of rhizospheric microbes, especially Acidobacteriaceae subgroup 1, DA111, and Acidobacteria.
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Affiliation(s)
- Xiumei Tang
- Agricultural College of Guangxi University, Nanning, Guangxi, China.,Cash Crops Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Jing Jiang
- Cash Crops Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Zhipeng Huang
- Cash Crops Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Haining Wu
- Cash Crops Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Jin Wang
- Agricultural Resource and Environment Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Liangqiong He
- Cash Crops Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Faqian Xiong
- Cash Crops Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Ruichun Zhong
- Cash Crops Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Jing Liu
- Cash Crops Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Zhuqiang Han
- Cash Crops Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Ronghua Tang
- Cash Crops Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Longfei He
- Agricultural College of Guangxi University, Nanning, Guangxi, China
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15
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Sheremet A, Jones GM, Jarett J, Bowers RM, Bedard I, Culham C, Eloe-Fadrosh EA, Ivanova N, Malmstrom RR, Grasby SE, Woyke T, Dunfield PF. Ecological and genomic analyses of candidate phylum WPS-2 bacteria in an unvegetated soil. Environ Microbiol 2020; 22:3143-3157. [PMID: 32372527 DOI: 10.1111/1462-2920.15054] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 04/28/2020] [Accepted: 04/29/2020] [Indexed: 12/01/2022]
Abstract
Members of the bacterial candidate phylum WPS-2 (or Eremiobacterota) are abundant in several dry, bare soil environments. In a bare soil deposited by an extinct iron-sulfur spring, we found that WPS-2 comprised up to 24% of the bacterial community and up to 108 cells per g of soil based on 16S rRNA gene sequencing and quantification. A single genus-level cluster (Ca. Rubrimentiphilum) predominated in bare soils but was less abundant in adjacent forest. Nearly complete genomes of Ca. Rubrimentiphilum were recovered as single amplified genomes (SAGs) and metagenome-assembled genomes (MAGs). Surprisingly, given the abundance of WPS-2 in bare soils, the genomes did not indicate any capacity for autotrophy, phototrophy, or trace gas metabolism. Instead, they suggest a predominantly aerobic organoheterotrophic lifestyle, perhaps based on scavenging amino acids, nucleotides, and complex oligopeptides, along with lithotrophic capacity on thiosulfate. Network analyses of the entire community showed that some species of Chloroflexi, Actinobacteria, and candidate phylum AD3 (or Dormibacterota) co-occurred with Ca. Rubrimentiphilum and may represent ecological or metabolic partners. We propose that Ca. Rubrimentiphilum act as efficient heterotrophic scavengers. Combined with previous studies, these data suggest that the phylum WPS-2 includes bacteria with diverse metabolic capabilities.
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Affiliation(s)
- Andriy Sheremet
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW Calgary, Alberta, T2N 1N4, Canada
| | - Gareth M Jones
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW Calgary, Alberta, T2N 1N4, Canada
| | - Jessica Jarett
- Department of Energy Joint Genome Institute, Walnut Creek CA, 94598, USA
| | - Robert M Bowers
- Department of Energy Joint Genome Institute, Walnut Creek CA, 94598, USA
| | - Isaac Bedard
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW Calgary, Alberta, T2N 1N4, Canada
| | - Cassandra Culham
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW Calgary, Alberta, T2N 1N4, Canada
| | | | - Natalia Ivanova
- Department of Energy Joint Genome Institute, Walnut Creek CA, 94598, USA
| | - Rex R Malmstrom
- Department of Energy Joint Genome Institute, Walnut Creek CA, 94598, USA
| | | | - Tanja Woyke
- Department of Energy Joint Genome Institute, Walnut Creek CA, 94598, USA
| | - Peter F Dunfield
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW Calgary, Alberta, T2N 1N4, Canada
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16
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Manikkam R, Imchen M, Kaari M, Angamuthu V, Venugopal G, Thangavel S, Joseph J, Ramasamy B, Kumavath R. Metagenomic insights unveil the dominance of undescribed Actinobacteria in pond ecosystem of an Indian shrine. Meta Gene 2020. [DOI: 10.1016/j.mgene.2019.100639] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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17
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Suleiman AKA, Harkes P, van den Elsen S, Holterman M, Korthals GW, Helder J, Kuramae EE. Organic amendment strengthens interkingdom associations in the soil and rhizosphere of barley (Hordeum vulgare). THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 695:133885. [PMID: 31756853 DOI: 10.1016/j.scitotenv.2019.133885] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/25/2019] [Accepted: 08/10/2019] [Indexed: 06/10/2023]
Abstract
Anthropogenic modification of soil systems has diverse impacts on food web interactions and ecosystem functioning. To understand the positive, neutral or adverse effects of agricultural practices on the associations of community members of soil microbes and microfaunal biomes, we characterized the effects of different fertilization types (organic, inorganic and a combination of organic and inorganic) on the food web active communities in the bulk soil and rhizosphere compartments in field conditions. We examined the influence of fertilization on (i) individual groups (bacteria, protozoa and fungi as microbe representatives and metazoans as microfauna representatives) and (ii) inter-kingdom interactions (focusing on the interactions between bacteria and eukaryotic groups) both neglecting and considering environmental factors in our analysis in combination with the microbial compositional data. Our results revealed different patterns of biota communities under organic versus inorganic fertilization, which shaped food web associations in both the bulk and rhizosphere compartments. Overall, organic fertilization increased the complexity of microbial-microfaunal ecological associations with inter- and intra- connections among categories of primary decomposers (bacteria and fungi) and predators (protozoa and microfauna) and differences in potential function in the soil food web in both the bulk and rhizosphere compartments. Furthermore, the inter-connections between primary decomposers and predators in bulk soil were more pronounced when environmental factors were considered. We suggest that organic fertilization selects bacterial orders with different potential ecological functions and interactions as survival, predation and cooperation due to more complex environment than those of inorganic or combined fertilization. Our findings support the importance of a comprehensive understanding of trophic food web patterns for soil management systems.
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Affiliation(s)
- Afnan K A Suleiman
- Netherlands Institute of Ecology (NIOO-KNAW), Department of Microbial Ecology, Wageningen, the Netherlands.
| | - Paula Harkes
- Wageningen University and Research Centre (WUR), Laboratory of Nematology, Wageningen, the Netherlands.
| | - Sven van den Elsen
- Wageningen University and Research Centre (WUR), Laboratory of Nematology, Wageningen, the Netherlands.
| | - Martijn Holterman
- Wageningen University and Research Centre (WUR), Laboratory of Nematology, Wageningen, the Netherlands.
| | - Gerard W Korthals
- Netherlands Institute of Ecology (NIOO-KNAW), Department of Microbial Ecology, Wageningen, the Netherlands; Wageningen University and Research Centre (WUR), Laboratory of Nematology, Wageningen, the Netherlands.
| | - Johannes Helder
- Wageningen University and Research Centre (WUR), Laboratory of Nematology, Wageningen, the Netherlands
| | - Eiko E Kuramae
- Netherlands Institute of Ecology (NIOO-KNAW), Department of Microbial Ecology, Wageningen, the Netherlands.
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18
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Soil Microbiota of Dystric Cambisol in the High Tatra Mountains (Slovakia) after Windthrow. SUSTAINABILITY 2019. [DOI: 10.3390/su11236851] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
There has been much more damage to forests in the Slovak Republic in the second half of the 20th century than to other European countries. Forested mountain massifs have become a filter of industrial and transportation emissions from abroad, as well as from domestic origins. There are not only acidic deposits of sulphur and heavy metals present in forest soils, but other additional environmental problems, such as climate change, storms, fires, floods, droughts, are worsening the situation. Therefore, forest terrestrial ecosystems are becoming more vulnerable due to changes in natural and environmental conditions. In the High Tatra Mountains in Slovakia, which are protected as a national park, four internationally monitored localities were established after the windthrow disaster in 2004 and fire in 2005: REF, with intact forest; EXT, with extracted wood mass; NEX, with non-extracted wood mass; and FIR, the burnt locality. Soils from these localities were microbiologically analysed with special attention to fungi. Bacterial microbiota detected by high-throughput sequencing showed the prevalence of the genera Acidothermus, Mycobacterium, and Nocardia, and a very low presence of the genera Acidibacter, Burkholderia-Paraburkholderia, Optitus and the uncultured genus Desulfurellaceae H16 in the soil sample from the burnt locality when compared with the unburned sites. Additionally, soil mycocoenoses showed a low similarity between the locality with an intact forest ecosystem and the localities with extracted (REF–EXT) and non-extracted (REF–NEX) wood mass. There was no similarity with the burnt locality (FIR), where heat-resistant fungi dominated. It was shown that the windthrow disaster and subsequent extraction or non-extraction of wood mass did not affect the soil microbial communities or their development. On the other hand, the influence of fire was significant.
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19
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Lukhele T, Selvarajan R, Nyoni H, Mamba BB, Msagati TAM. Diversity and functional profile of bacterial communities at Lancaster acid mine drainage dam, South Africa as revealed by 16S rRNA gene high-throughput sequencing analysis. Extremophiles 2019; 23:719-734. [PMID: 31520125 DOI: 10.1007/s00792-019-01130-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 08/14/2019] [Indexed: 12/23/2022]
Abstract
This study surveyed physicochemical properties and bacterial community structure of water and sediments from an acid mine drainage (AMD) dam in South Africa. High-throughput sequence analysis revealed low diversity bacterial communities affiliated within 8 dominant phyla; Acidobacteria, Actinobacteria, Chloroflexi, Firmicutes, Nitrospirae, Proteobacteria, Saccharibacteria, and ca. TM6_(Dependentiae). Acidiphilium spp. which are common AMD inhabitants but rarely occur as dominant taxa, were the most abundant in both AMD water and sediments. Other groups making up the community are less common AMD inhabitants; Acidibacillus, Acidibacter, Acidobacterium, Acidothermus, Legionella, Metallibacterium, Mycobacterium, as well as elusive taxa (Saccharibacteria, ca. TM6_(Dependentiae) and ca. JG37-AG-4). Although most of the taxa are shared between sediment and water communities, alpha diversity indices indicate a higher species richness in the sediments. From canonical correspondence analysis, DOC, Mn, Cu, Cr, Al, Fe, Ca were identified as important determinants of community structure in water, compared to DOC, Ca, Cu, Fe, Zn, Mg, K, Mn, Al, sulfates, and nitrates in sediments. Predictive functional profiling recovered genes associated with bacterial growth and those related to survival and adaptation to the harsh environmental conditions. Overall, the study reports on a distinct AMD bacterial community and highlights sediments as microhabitats with higher species richness than water.
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Affiliation(s)
- Thabile Lukhele
- Nanotechnology and Water Sustainability Research Unit, College of Science Engineering and Technology, University of South Africa, Science Campus, Johannesburg, 1709, South Africa
| | - Ramganesh Selvarajan
- College of Agriculture and Environmental Sciences, University of South Africa, Science Campus, Johannesburg, 1709, South Africa
| | - Hlengilizwe Nyoni
- Nanotechnology and Water Sustainability Research Unit, College of Science Engineering and Technology, University of South Africa, Science Campus, Johannesburg, 1709, South Africa
| | - Bheki Brilliance Mamba
- Nanotechnology and Water Sustainability Research Unit, College of Science Engineering and Technology, University of South Africa, Science Campus, Johannesburg, 1709, South Africa.,State Key Laboratory of Separation and Membranes, Membrane Processes, National Center for International Joint Research on Membrane Science and Technology, Tianjin, 300387, People's Republic of China
| | - Titus Alfred Makudali Msagati
- Nanotechnology and Water Sustainability Research Unit, College of Science Engineering and Technology, University of South Africa, Science Campus, Johannesburg, 1709, South Africa.
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20
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Nguyen TV, Wibberg D, Vigil-Stenman T, Berckx F, Battenberg K, Demchenko KN, Blom J, Fernandez MP, Yamanaka T, Berry AM, Kalinowski J, Brachmann A, Pawlowski K. Frankia-Enriched Metagenomes from the Earliest Diverging Symbiotic Frankia Cluster: They Come in Teams. Genome Biol Evol 2019; 11:2273-2291. [PMID: 31368478 PMCID: PMC6735867 DOI: 10.1093/gbe/evz153] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/10/2019] [Indexed: 11/14/2022] Open
Abstract
Frankia strains induce the formation of nitrogen-fixing nodules on roots of actinorhizal plants. Phylogenetically, Frankia strains can be grouped in four clusters. The earliest divergent cluster, cluster-2, has a particularly wide host range. The analysis of cluster-2 strains has been hampered by the fact that with two exceptions, they could never be cultured. In this study, 12 Frankia-enriched metagenomes of Frankia cluster-2 strains or strain assemblages were sequenced based on seven inoculum sources. Sequences obtained via DNA isolated from whole nodules were compared with those of DNA isolated from fractionated preparations enhanced in the Frankia symbiotic structures. The results show that cluster-2 inocula represent groups of strains, and that strains not represented in symbiotic structures, that is, unable to perform symbiotic nitrogen fixation, may still be able to colonize nodules. Transposase gene abundance was compared in the different Frankia-enriched metagenomes with the result that North American strains contain more transposase genes than Eurasian strains. An analysis of the evolution and distribution of the host plants indicated that bursts of transposition may have coincided with niche competition with other cluster-2 Frankia strains. The first genome of an inoculum from the Southern Hemisphere, obtained from nodules of Coriaria papuana in Papua New Guinea, represents a novel species, postulated as Candidatus Frankia meridionalis. All Frankia-enriched metagenomes obtained in this study contained homologs of the canonical nod genes nodABC; the North American genomes also contained the sulfotransferase gene nodH, while the genome from the Southern Hemisphere only contained nodC and a truncated copy of nodB.
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Affiliation(s)
- Thanh Van Nguyen
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Sweden
| | - Daniel Wibberg
- Center for Biotechnology (CeBiTec), Bielefeld University, Germany
| | | | - Fede Berckx
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Sweden
| | - Kai Battenberg
- Department of Plant Sciences, University of California, Davis
| | - Kirill N Demchenko
- Laboratory of Cellular and Molecular Mechanisms of Plant Development, Komarov Botanical Institute, Russian Academy of Sciences, Saint Petersburg, Russia
- Laboratory of Molecular and Cellular Biology, All-Russia Research Institute for Agricultural Microbiology, Saint Petersburg, Russia
| | - Jochen Blom
- Bioinformatics and Systems Biology, Justus Liebig University, Gießen, Germany
| | - Maria P Fernandez
- Ecologie Microbienne, Centre National de la Recherche Scientifique UMR 5557, Université Lyon I, Villeurbanne Cedex, France
| | | | - Alison M Berry
- Department of Plant Sciences, University of California, Davis
| | - Jörn Kalinowski
- Center for Biotechnology (CeBiTec), Bielefeld University, Germany
| | - Andreas Brachmann
- Biocenter, Ludwig Maximilians University Munich, Planegg-Martinsried, Germany
| | - Katharina Pawlowski
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Sweden
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21
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Knapik K, Becerra M, González-Siso MI. Microbial diversity analysis and screening for novel xylanase enzymes from the sediment of the Lobios Hot Spring in Spain. Sci Rep 2019; 9:11195. [PMID: 31371784 PMCID: PMC6671963 DOI: 10.1038/s41598-019-47637-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 07/11/2019] [Indexed: 01/28/2023] Open
Abstract
Here, we describe the metagenome composition of a microbial community in a hot spring sediment as well as a sequence-based and function-based screening of the metagenome for identification of novel xylanases. The sediment was collected from the Lobios Hot Spring located in the province of Ourense (Spain). Environmental DNA was extracted and sequenced using Illumina technology, and a total of 3.6 Gbp of clean paired reads was produced. A taxonomic classification that was obtained by comparison to the NCBI protein nr database revealed a dominance of Bacteria (93%), followed by Archaea (6%). The most abundant bacterial phylum was Acidobacteria (25%), while Thaumarchaeota (5%) was the main archaeal phylum. Reads were assembled into contigs. Open reading frames (ORFs) predicted on these contigs were searched by BLAST against the CAZy database to retrieve xylanase encoding ORFs. A metagenomic fosmid library of approximately 150,000 clones was constructed to identify functional genes encoding thermostable xylanase enzymes. Function-based screening revealed a novel xylanase-encoding gene (XynA3), which was successfully expressed in E. coli BL21. The resulting protein (41 kDa), a member of glycoside hydrolase family 11 was purified and biochemically characterized. The highest activity was measured at 80 °C and pH 6.5. The protein was extremely thermostable and showed 94% remaining activity after incubation at 60 °C for 24 h and over 70% remaining activity after incubation at 70 °C for 24 h. Xylanolytic activity of the XynA3 enzyme was stimulated in the presence of β-mercaptoethanol, dithiothreitol and Fe3+ ions. HPLC analysis showed that XynA3 hydrolyzes xylan forming xylobiose with lower proportion of xylotriose and xylose. Specific activity of the enzyme was 9080 U/mg for oat arabinoxylan and 5080 U/mg for beechwood xylan, respectively, without cellulase activity.
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Affiliation(s)
- Kamila Knapik
- Universidade da Coruña, Grupo EXPRELA, Facultade de Ciencias, Centro de Investigacións Científicas Avanzadas (CICA), A Coruña, Spain
| | - Manuel Becerra
- Universidade da Coruña, Grupo EXPRELA, Facultade de Ciencias, Centro de Investigacións Científicas Avanzadas (CICA), A Coruña, Spain
| | - María-Isabel González-Siso
- Universidade da Coruña, Grupo EXPRELA, Facultade de Ciencias, Centro de Investigacións Científicas Avanzadas (CICA), A Coruña, Spain.
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22
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Sun W, Sun X, Li B, Häggblom MM, Han F, Xiao E, Zhang M, Wang Q, Li F. Bacterial response to antimony and arsenic contamination in rice paddies during different flooding conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 675:273-285. [PMID: 31030134 DOI: 10.1016/j.scitotenv.2019.04.146] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 03/31/2019] [Accepted: 04/10/2019] [Indexed: 06/09/2023]
Abstract
Rice is more vulnerable to arsenic (As) and antimony (Sb) contamination than other cereals due to the special cultivation methods, during which irrigation conditions are adjusted depending upon the growth stages. The changes in irrigation conditions may alter the oxidation states of Sb and As, which influences their mobility and bioavailability and hence uptake by rice. In this study, bacterial responses to As and Sb contamination in rice fields were investigated during two different stages of rice growth: the vegetative stage (flooded conditions), and the ripening stage (drained conditions). The substantial changes in the irrigation conditions caused a variation in geochemical parameters including the As- and Sb-extractable fractions. As and Sb were more mobile and bioaccessible during the flooded than under drained conditions. The microbial communities varied during two irrigation conditions, suggesting that the geochemical conditions may have different effects on the innate paddy microbiota. Therefore, various statistical tools including co-occurrence network and random forest (RF) were performed to reveal the environment-microbe interactions in two different irrigation conditions. One of the notable findings is that Sb- and As-related parameters exerted more influences during the flooded than under drained conditions. Furthermore, a detailed RF analysis indicated that the individual bacterial taxa may also respond differently to contaminant fractions during the two irrigation conditions. Notably, RF indicated that individual taxa such as Clostridiaceae and Geobacter may be responsible for biotransformation of As and Sb (e.g., As and Sb reduction). The results provided knowledge for As and Sb transformation during contrasting irrigation conditions and the potential mitigation strategy for contaminant removal.
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Affiliation(s)
- Weimin Sun
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China.
| | - Xiaoxu Sun
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
| | - Baoqin Li
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
| | - Max M Häggblom
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ 08901, USA
| | - Feng Han
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
| | - Enzong Xiao
- Key Laboratory of Water Quality and Conservation in the Pearl River Delta, Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China
| | - Miaomiao Zhang
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
| | - Qi Wang
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
| | - Fangbai Li
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
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23
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Dukunde A, Schneider D, Schmidt M, Veldkamp E, Daniel R. Tree Species Shape Soil Bacterial Community Structure and Function in Temperate Deciduous Forests. Front Microbiol 2019; 10:1519. [PMID: 31338079 PMCID: PMC6629791 DOI: 10.3389/fmicb.2019.01519] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 06/18/2019] [Indexed: 01/23/2023] Open
Abstract
Amplicon-based analysis of 16S rRNA genes and transcripts was used to assess the effect of tree species composition on soil bacterial community structure and function in a temperate deciduous forest. Samples were collected from mono and mixed stands of Fagus sylvatica (beech), Carpinus betulus (hornbeam), Tilia sp. (lime), and Quercus sp. (oak) in spring, summer, and autumn. Soil bacterial community exhibited similar taxonomic composition at total (DNA-based) and potentially active community (RNA-based) level, with fewer taxa present at active community level. Members of Rhizobiales dominated at both total and active bacterial community level, followed by members of Acidobacteriales, Solibacterales, Rhodospirillales, and Xanthomonadales. Bacterial communities at total and active community level showed a significant positive correlation with tree species identity (mono stands) and to a lesser extent with tree species richness (mixed stands). Approximately 58 and 64% of indicator operational taxonomic units (OTUs) showed significant association with only one mono stand at total and active community level, respectively, indicating a strong impact of tree species on soil bacterial community composition. Soil C/N ratio, pH, and P content similarly exhibited a significant positive correlation with soil bacterial communities, which was attributed to direct and indirect effects of forest stands. Seasonality was the strongest driver of predicted metabolic functions related to C fixation and degradation, and N metabolism. Carbon and nitrogen metabolic processes were significantly abundant in spring, while C degradation gene abundances increased from summer to autumn, corresponding to increased litterfall and decomposition. The results revealed that in a spatially homogenous forest soil, tree species diversity and richness are dominant drivers of structure and composition in soil bacterial communities.
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Affiliation(s)
- Amélie Dukunde
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August University of Göttingen, Göttingen, Germany
| | - Dominik Schneider
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August University of Göttingen, Göttingen, Germany
| | - Marcus Schmidt
- Soil Science of Tropical and Subtropical Ecosystems, Faculty of Forest Sciences and Forest Ecology, Büsgen Institute, Georg-August University of Göttingen, Göttingen, Germany
| | - Edzo Veldkamp
- Soil Science of Tropical and Subtropical Ecosystems, Faculty of Forest Sciences and Forest Ecology, Büsgen Institute, Georg-August University of Göttingen, Göttingen, Germany
| | - Rolf Daniel
- Göttingen Genomics Laboratory, Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August University of Göttingen, Göttingen, Germany
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Sahoo K, Sahoo RK, Gaur M, Subudhi E. Cellulolytic thermophilic microorganisms in white biotechnology: a review. Folia Microbiol (Praha) 2019; 65:25-43. [DOI: 10.1007/s12223-019-00710-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 04/15/2019] [Indexed: 10/26/2022]
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25
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Characterization of a Thermophilic Monosaccharide Stimulated β-Glucosidase from Acidothermus cellulolyticus. Chem Res Chin Univ 2018. [DOI: 10.1007/s40242-018-7408-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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26
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A novel trifunctional, family GH10 enzyme from Acidothermus cellulolyticus 11B, exhibiting endo-xylanase, arabinofuranosidase and acetyl xylan esterase activities. Extremophiles 2017; 22:109-119. [DOI: 10.1007/s00792-017-0981-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 11/14/2017] [Indexed: 10/18/2022]
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Kim SK, Chung D, Himmel ME, Bomble YJ, Westpheling J. In vivo synergistic activity of a CAZyme cassette from Acidothermus cellulolyticus significantly improves the cellulolytic activity of the C. bescii exoproteome. Biotechnol Bioeng 2017. [PMID: 28650071 DOI: 10.1002/bit.26366] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The use of microbial cells to convert plant biomass directly to fuels and chemicals is referred to as consolidated bioprocessing (CBP). Members of the bacterial genus, Caldicellulosiruptor (Gram-positive, anaerobic hyperthermophiles) are capable of deconstructing plant biomass without enzymatic or chemical pretreatment. This is accomplished by the production and secretion of free, multi-domain enzymes that outperform commercial enzyme cocktails on some substrates. Here, we show that the exoproteome of Caldicellulosiruptor bescii may be enhanced by the heterologous expression of enzymes from Acidothermus cellulolyticus that act synergistically to improve sugar release from complex substrates; as well as improve cell growth. In this work, co-expression of the A. cellulolyticus Acel_0615 β-glucanase (GH6 and GH12) and E1 endoglucanase (GH5) enzymes resulted in an increase in the activity of the exoproteome on Avicel; as well as an increase in growth of C. bescii on Avicel compared to the parental strain or the strain expressing the β-glucanase alone. Our ability to engineer the composition and effectiveness of the exoproteome of these bacteria provides insight into the natural mechanism of plant cell wall deconstruction, as well as future directions for improving CBP. Biotechnol. Bioeng. 2017;114: 2474-2480. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Sun-Ki Kim
- Department of Genetics, University of Georgia, Athens, Georgia, 30602.,The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831
| | - Daehwan Chung
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831.,Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado
| | - Michael E Himmel
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831.,Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado
| | - Yannick J Bomble
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831.,Biosciences Center, National Renewable Energy Laboratory, Golden, Colorado
| | - Janet Westpheling
- Department of Genetics, University of Georgia, Athens, Georgia, 30602.,The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831
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SSUnique: Detecting Sequence Novelty in Microbiome Surveys. mSystems 2016; 1:mSystems00133-16. [PMID: 28028549 PMCID: PMC5183599 DOI: 10.1128/msystems.00133-16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Accepted: 11/23/2016] [Indexed: 11/20/2022] Open
Abstract
Extensive SSU rRNA gene sequence libraries, constructed from DNA extracts of environmental or host-associated samples, often contain many unclassified sequences, many representing organisms with novel taxonomy (taxonomic “blind spots”) and potentially unique ecology. This novelty is poorly explored in standard workflows, which narrows the breadth and discovery potential of such studies. Here we present the SSUnique analysis pipeline, which will promote the exploration of unclassified diversity in microbiome research and, importantly, enable the discovery of substantial novel taxonomic lineages through the analysis of a large variety of existing data sets. High-throughput sequencing of small-subunit (SSU) rRNA genes has revolutionized understanding of microbial communities and facilitated investigations into ecological dynamics at unprecedented scales. Such extensive SSU rRNA gene sequence libraries, constructed from DNA extracts of environmental or host-associated samples, often contain a substantial proportion of unclassified sequences, many representing organisms with novel taxonomy (taxonomic “blind spots”) and potentially unique ecology. Indeed, these novel taxonomic lineages are associated with so-called microbial “dark matter,” which is the genomic potential of these lineages. Unfortunately, characterization beyond “unclassified” is challenging due to relatively short read lengths and large data set sizes. Here we demonstrate how mining of phylogenetically novel sequences from microbial ecosystems can be automated using SSUnique, a software pipeline that filters unclassified and/or rare operational taxonomic units (OTUs) from 16S rRNA gene sequence libraries by screening against consensus structural models for SSU rRNA. Phylogenetic position is inferred against a reference data set, and additional characterization of novel clades is also included, such as targeted probe/primer design and mining of assembled metagenomes for genomic context. We show how SSUnique reproduced a previous analysis of phylogenetic novelty from an Arctic tundra soil and demonstrate the recovery of highly novel clades from data sets associated with both the Earth Microbiome Project (EMP) and Human Microbiome Project (HMP). We anticipate that SSUnique will add to the expanding computational toolbox supporting high-throughput sequencing approaches for the study of microbial ecology and phylogeny. IMPORTANCE Extensive SSU rRNA gene sequence libraries, constructed from DNA extracts of environmental or host-associated samples, often contain many unclassified sequences, many representing organisms with novel taxonomy (taxonomic “blind spots”) and potentially unique ecology. This novelty is poorly explored in standard workflows, which narrows the breadth and discovery potential of such studies. Here we present the SSUnique analysis pipeline, which will promote the exploration of unclassified diversity in microbiome research and, importantly, enable the discovery of substantial novel taxonomic lineages through the analysis of a large variety of existing data sets.
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Pb 2+ Effects on Growth, Lipids, and Protein and DNA Profiles of the Thermophilic Bacterium Thermus Thermophilus. Microorganisms 2016; 4:microorganisms4040045. [PMID: 27929414 PMCID: PMC5192528 DOI: 10.3390/microorganisms4040045] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/21/2016] [Accepted: 11/28/2016] [Indexed: 11/30/2022] Open
Abstract
Extremophiles are organisms able to thrive in extreme environmental conditions and some of them show the ability to survive high doses of heavy metals thanks to defensive mechanisms provided by primary and secondary metabolic products, i.e., extremolytes, lipids, and extremozymes. This is why there is a growing scientific and industrial interest in the use of thermophilic bacteria in a host of tasks, from the environmental detoxification of heavy metal to industrial activities, such as bio-machining and bio-metallurgy. In this work Thermus thermophilus was challenged against increasing Pb2+ concentrations spanning from 0 to 300 ppm in order to ascertain the sensitiveness of this bacteria to the Pb environmental pollution and to give an insight on its heavy metal resistance mechanisms. Analysis of growth parameters, enzyme activities, protein profiles, and lipid membrane modifications were carried out. In addition, genotyping analysis of bacteria grown in the presence of Pb2+, using random amplified polymorphic DNA-PCR and DNA melting evaluation, were also performed. A better knowledge of the response of thermophilic bacteria to the different pollutants, as heavy metals, is necessary for optimizing their use in remediation or decontamination processes.
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Loder AJ, Zeldes BM, Conway JM, Counts JA, Straub CT, Khatibi PA, Lee LL, Vitko NP, Keller MW, Rhaesa AM, Rubinstein GM, Scott IM, Lipscomb GL, Adams MW, Kelly RM. Extreme Thermophiles as Metabolic Engineering Platforms: Strategies and Current Perspective. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1002/9783527807796.ch14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Andrew J. Loder
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Benjamin M. Zeldes
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Jonathan M. Conway
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - James A. Counts
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Christopher T. Straub
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Piyum A. Khatibi
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Laura L. Lee
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Nicholas P. Vitko
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
| | - Matthew W. Keller
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Amanda M. Rhaesa
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Gabe M. Rubinstein
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Israel M. Scott
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Gina L. Lipscomb
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Michael W.W. Adams
- University of Georgia; Department of Biochemistry and Molecular Biology; Life Sciences Bldg., University of Georgia, Athens GA 30602-7229, USA
| | - Robert M. Kelly
- North Carolina State University; Department of Chemical and Biomolecular Engineering; EB-1, 911 Partners Way Raleigh NC 27695-7905 USA
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Nguyen TV, Wibberg D, Battenberg K, Blom J, Vanden Heuvel B, Berry AM, Kalinowski J, Pawlowski K. An assemblage of Frankia Cluster II strains from California contains the canonical nod genes and also the sulfotransferase gene nodH. BMC Genomics 2016; 17:796. [PMID: 27729005 PMCID: PMC5059922 DOI: 10.1186/s12864-016-3140-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 09/28/2016] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND The ability to establish root nodule symbioses is restricted to four different plant orders. Soil actinobacteria of the genus Frankia can establish a symbiotic relationship with a diverse group of plants within eight different families from three different orders, the Cucurbitales, Fagales and Rosales. Phylogenetically, Frankia strains can be divided into four clusters, three of which (I, II, III) contain symbiotic strains. Members of Cluster II nodulate the broadest range of host plants with species from four families from two different orders, growing on six continents. Two Cluster II genomes were sequenced thus far, both from Asia. RESULTS In this paper we present the first Frankia cluster II genome from North America (California), Dg2, which represents a metagenome of two major and one minor strains. A phylogenetic analysis of the core genomes of 16 Frankia strains shows that Cluster II the ancestral group in the genus, also ancestral to the non-symbiotic Cluster IV. Dg2 contains the canonical nod genes nodABC for the production of lipochitooligosaccharide Nod factors, but also two copies of the sulfotransferase gene nodH. In rhizobial systems, sulfation of Nod factors affects their host specificity and their stability. CONCLUSIONS A comparison with the nod gene region of the previously sequenced Dg1 genome from a Cluster II strain from Pakistan shows that the common ancestor of both strains should have contained nodABC and nodH. Phylogenetically, Dg2 NodH proteins are sister to rhizobial NodH proteins. A glnA-based phylogenetic analysis of all Cluster II strains sampled thus far supports the hypothesis that Cluster II Frankia strains came to North America with Datisca glomerata following the Madrean-Tethyan pattern.
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Affiliation(s)
- Thanh Van Nguyen
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 106 91, Stockholm, Sweden
| | - Daniel Wibberg
- Center for Biotechnology, Bielefeld University, 33615, Bielefeld, Germany
| | - Kai Battenberg
- Department of Plant Sciences, University of California Davis, Davis, CA, 95616, USA
| | - Jochen Blom
- Bioinformatics and Systems Biology, Justus Liebig University, 35392, Giessen, Germany
| | | | - Alison M Berry
- Department of Plant Sciences, University of California Davis, Davis, CA, 95616, USA
| | - Jörn Kalinowski
- Center for Biotechnology, Bielefeld University, 33615, Bielefeld, Germany
| | - Katharina Pawlowski
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 106 91, Stockholm, Sweden.
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Comparative Community Proteomics Demonstrates the Unexpected Importance of Actinobacterial Glycoside Hydrolase Family 12 Protein for Crystalline Cellulose Hydrolysis. mBio 2016; 7:mBio.01106-16. [PMID: 27555310 PMCID: PMC4999548 DOI: 10.1128/mbio.01106-16] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Glycoside hydrolases (GHs) are key enzymes in the depolymerization of plant-derived cellulose, a process central to the global carbon cycle and the conversion of plant biomass to fuels and chemicals. A limited number of GH families hydrolyze crystalline cellulose, often by a processive mechanism along the cellulose chain. During cultivation of thermophilic cellulolytic microbial communities, substantial differences were observed in the crystalline cellulose saccharification activities of supernatants recovered from divergent lineages. Comparative community proteomics identified a set of cellulases from a population closely related to actinobacterium Thermobispora bispora that were highly abundant in the most active consortium. Among the cellulases from T. bispora, the abundance of a GH family 12 (GH12) protein correlated most closely with the changes in crystalline cellulose hydrolysis activity. This result was surprising since GH12 proteins have been predominantly characterized as enzymes active on soluble polysaccharide substrates. Heterologous expression and biochemical characterization of the suite of T. bispora hydrolytic cellulases confirmed that the GH12 protein possessed the highest activity on multiple crystalline cellulose substrates and demonstrated that it hydrolyzes cellulose chains by a predominantly random mechanism. This work suggests that the role of GH12 proteins in crystalline cellulose hydrolysis by cellulolytic microbes should be reconsidered. Cellulose is the most abundant organic polymer on earth, and its enzymatic hydrolysis is a key reaction in the global carbon cycle and the conversion of plant biomass to biofuels. The glycoside hydrolases that depolymerize crystalline cellulose have been primarily characterized from isolates. In this study, we demonstrate that adapting microbial consortia from compost to grow on crystalline cellulose generated communities whose soluble enzymes exhibit differential abilities to hydrolyze crystalline cellulose. Comparative proteomics of these communities identified a protein of glycoside hydrolase family 12 (GH12), a family of proteins previously observed to primarily hydrolyze soluble substrates, as a candidate that accounted for some of the differences in hydrolytic activities. Heterologous expression confirmed that the GH12 protein identified by proteomics was active on crystalline cellulose and hydrolyzed cellulose by a random mechanism, in contrast to most cellulases that act on the crystalline polymer in a processive mechanism.
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Characterization of PAS domains in Frankia and selected Actinobacteria and their possible interaction with other co-domains for environmental adaptation. Symbiosis 2016. [DOI: 10.1007/s13199-016-0413-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Kim SK, Chung D, Himmel ME, Bomble YJ, Westpheling J. Heterologous expression of family 10 xylanases from Acidothermus cellulolyticus enhances the exoproteome of Caldicellulosiruptor bescii and growth on xylan substrates. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:176. [PMID: 27555882 PMCID: PMC4994175 DOI: 10.1186/s13068-016-0588-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 08/15/2016] [Indexed: 05/20/2023]
Abstract
BACKGROUND The ability to deconstruct plant biomass without conventional pretreatment has made members of the genus Caldicellulosiruptor the target of investigation for the consolidated processing of lignocellulosic biomass to biofuels and bioproducts. These Gram-positive bacteria are hyperthermophilic anaerobes and the most thermophilic cellulolytic organisms so far described. They use both C5 and C6 sugars simultaneously and have the ability to grow well on xylan, a major component of plant cell walls. This is an important advantage for their use to efficiently convert biomass at yields sufficient for an industrial process. For commodity chemicals, yield from substrate is perhaps the most important economic factor. In an attempt to improve even further the ability of C. bescii to use xylan, we introduced two xylanases from Acidothermus cellulolyticus. Acel_0180 includes tandem carbohydrate-binding modules (CBM2 and CBM3) located at the C-terminus, one of which, CBM2, is not present in C. bescii. Also, the sequences of Xyn10A and Acel_0180 have very little homology with the GH10 domains present in C. bescii. For these reasons, we selected these xylanases as potential candidates for synergistic interaction with those in the C. bescii exoproteome. RESULTS Heterologous expression of two xylanases from Acidothermus cellulolyticus in Caldicellulosiruptor bescii resulted in a modest, but significant increase in the activity of the exoproteome of C. bescii on xylan substrates. Even though the increase in extracellular activity was modest, the ability of C. bescii to grow on these substrates was dramatically improved suggesting that the xylan substrate/microbe interaction substantially increased deconstruction over the secreted free enzymes alone. CONCLUSIONS We anticipate that the ability to efficiently use xylan, a major component of plant cell walls for conversion of plant biomass to products of interest, will allow the conversion of renewable, sustainable, and inexpensive plant feedstocks to products at high yields.
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Affiliation(s)
- Sun-Ki Kim
- Department of Genetics, University of Georgia, Athens, GA USA
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN USA
| | - Daehwan Chung
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO USA
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN USA
| | - Michael E. Himmel
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO USA
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN USA
| | - Yannick J. Bomble
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO USA
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN USA
| | - Janet Westpheling
- Department of Genetics, University of Georgia, Athens, GA USA
- The BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN USA
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Wang J, Gao G, Li Y, Yang L, Liang Y, Jin H, Han W, Feng Y, Zhang Z. Cloning, Expression, and Characterization of a Thermophilic Endoglucanase, AcCel12B from Acidothermus cellulolyticus 11B. Int J Mol Sci 2015; 16:25080-95. [PMID: 26506341 PMCID: PMC4632791 DOI: 10.3390/ijms161025080] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 09/29/2015] [Accepted: 10/13/2015] [Indexed: 12/23/2022] Open
Abstract
The gene ABK52392 from the thermophilic bacterium Acidothermus cellulolyticus 11B was predicted to be endoglucanase and classified into glycoside hydrolase family 12. ABK52392 encodes a protein containing a catalytic domain and a carbohydrate binding module. ABK52392 was cloned and functionally expressed in Escherichia coli. After purification by Ni-NTA agarose affinity chromatography and Q-Sepharose® Fast Flow chromatography, the properties of the recombinant protein (AcCel12B) were characterized. AcCel12B exhibited optimal activity at pH 4.5 and 75 °C. The half-lives of AcCel12B at 60 and 70 °C were about 90 and 2 h, respectively, under acidic conditions. The specific hydrolytic activities of AcCel12B at 70 °C and pH 4.5 for sodium carboxymethylcellulose (CMC) and regenerated amorphous cellulose (RAC) were 118.3 and 104.0 U·mg−1, respectively. The Km and Vmax of AcCel12B for CMC were 25.47 mg·mL−1 and 131.75 U·mg−1, respectively. The time course of hydrolysis for RAC was investigated by measuring reducing ends in the soluble and insoluble phases. The total hydrolysis rate rapidly decreased after the early stage of incubation and the generation of insoluble reducing ends decreased earlier than that of soluble reducing ends. High thermostability of the cellulase indicates its potential commercial significance and it could be exploited for industrial application in the future.
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Affiliation(s)
- Junling Wang
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
- Department of Biotechnology, Jilin Agricultural Science and Technology College, Jilin 132101, China.
| | - Gui Gao
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Yuwei Li
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China.
| | - Liangzhen Yang
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Yanli Liang
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Hanyong Jin
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Weiwei Han
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Yan Feng
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
| | - Zuoming Zhang
- Key Laboratory for Molecular Enzymology & Engineering of the Ministry of Education, School of Life Science, Jilin University, Changchun 130012, China.
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Wang Q, Cen Z, Zhao J. The survival mechanisms of thermophiles at high temperatures: an angle of omics. Physiology (Bethesda) 2015; 30:97-106. [PMID: 25729055 DOI: 10.1152/physiol.00066.2013] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Thermophiles are referred to as microorganisms with optimal growth temperatures of >60 °C. Over the past few years, a number of studies have been conducted regarding thermophiles, especially using the omics strategies. This review provides a systematic view of the survival physiology of thermophiles from an "omics" perspective, which suggests that the adaptive ability of thermophiles is based on a cooperative mode with multi-dimensional regulations integrating genomics, transcriptomics, and proteomics.
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Affiliation(s)
- Quanhui Wang
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China; and BGI-Shenzhen, Shenzhen, China
| | - Zhen Cen
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China; and
| | - Jingjing Zhao
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China; and
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37
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Shivlata L, Satyanarayana T. Thermophilic and alkaliphilic Actinobacteria: biology and potential applications. Front Microbiol 2015; 6:1014. [PMID: 26441937 PMCID: PMC4585250 DOI: 10.3389/fmicb.2015.01014] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 09/07/2015] [Indexed: 11/13/2022] Open
Abstract
Microbes belonging to the phylum Actinobacteria are prolific sources of antibiotics, clinically useful bioactive compounds and industrially important enzymes. The focus of the current review is on the diversity and potential applications of thermophilic and alkaliphilic actinobacteria, which are highly diverse in their taxonomy and morphology with a variety of adaptations for surviving and thriving in hostile environments. The specific metabolic pathways in these actinobacteria are activated for elaborating pharmaceutically, agriculturally, and biotechnologically relevant biomolecules/bioactive compounds, which find multifarious applications.
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Persson T, Battenberg K, Demina IV, Vigil-Stenman T, Vanden Heuvel B, Pujic P, Facciotti MT, Wilbanks EG, O'Brien A, Fournier P, Cruz Hernandez MA, Mendoza Herrera A, Médigue C, Normand P, Pawlowski K, Berry AM. Candidatus Frankia Datiscae Dg1, the Actinobacterial Microsymbiont of Datisca glomerata, Expresses the Canonical nod Genes nodABC in Symbiosis with Its Host Plant. PLoS One 2015; 10:e0127630. [PMID: 26020781 PMCID: PMC4447401 DOI: 10.1371/journal.pone.0127630] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 04/16/2015] [Indexed: 11/18/2022] Open
Abstract
Frankia strains are nitrogen-fixing soil actinobacteria that can form root symbioses with actinorhizal plants. Phylogenetically, symbiotic frankiae can be divided into three clusters, and this division also corresponds to host specificity groups. The strains of cluster II which form symbioses with actinorhizal Rosales and Cucurbitales, thus displaying a broad host range, show suprisingly low genetic diversity and to date can not be cultured. The genome of the first representative of this cluster, Candidatus Frankia datiscae Dg1 (Dg1), a microsymbiont of Datisca glomerata, was recently sequenced. A phylogenetic analysis of 50 different housekeeping genes of Dg1 and three published Frankia genomes showed that cluster II is basal among the symbiotic Frankia clusters. Detailed analysis showed that nodules of D. glomerata, independent of the origin of the inoculum, contain several closely related cluster II Frankia operational taxonomic units. Actinorhizal plants and legumes both belong to the nitrogen-fixing plant clade, and bacterial signaling in both groups involves the common symbiotic pathway also used by arbuscular mycorrhizal fungi. However, so far, no molecules resembling rhizobial Nod factors could be isolated from Frankia cultures. Alone among Frankia genomes available to date, the genome of Dg1 contains the canonical nod genes nodA, nodB and nodC known from rhizobia, and these genes are arranged in two operons which are expressed in D. glomerata nodules. Furthermore, Frankia Dg1 nodC was able to partially complement a Rhizobium leguminosarum A34 nodC::Tn5 mutant. Phylogenetic analysis showed that Dg1 Nod proteins are positioned at the root of both α- and β-rhizobial NodABC proteins. NodA-like acyl transferases were found across the phylum Actinobacteria, but among Proteobacteria only in nodulators. Taken together, our evidence indicates an Actinobacterial origin of rhizobial Nod factors.
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Affiliation(s)
- Tomas Persson
- Department of Ecology, Environment and Plant Sciences, Lilla Frescati, Stockholm University, 106 91, Stockholm, Sweden
| | - Kai Battenberg
- Department of Plant Sciences, University of California Davis, Davis, California, 95616, United States of America
| | - Irina V. Demina
- Department of Ecology, Environment and Plant Sciences, Lilla Frescati, Stockholm University, 106 91, Stockholm, Sweden
| | - Theoden Vigil-Stenman
- Department of Ecology, Environment and Plant Sciences, Lilla Frescati, Stockholm University, 106 91, Stockholm, Sweden
| | - Brian Vanden Heuvel
- Department of Biology, Colorado State University, Pueblo, Colorado, 81001, United States of America
| | - Petar Pujic
- Université Lyon 1, Université Lyon, CNRS, Ecologie Microbienne UMR5557, 69622, Villeurbanne Cedex, France
| | - Marc T. Facciotti
- Department of Biomedical Engineering, University of California Davis, Davis, California, 95616, United States of America
- UC Davis Genome Center, University of California Davis, Davis, California, 95616, United States of America
| | - Elizabeth G. Wilbanks
- UC Davis Genome Center, University of California Davis, Davis, California, 95616, United States of America
| | - Anna O'Brien
- UC Davis Genome Center, University of California Davis, Davis, California, 95616, United States of America
| | - Pascale Fournier
- Université Lyon 1, Université Lyon, CNRS, Ecologie Microbienne UMR5557, 69622, Villeurbanne Cedex, France
| | | | - Alberto Mendoza Herrera
- Centro de Biotecnología Genómica, Instituto Politécnico Nacional, 88710, Reynosa, Tamaulipas, Mexico
| | | | - Philippe Normand
- Université Lyon 1, Université Lyon, CNRS, Ecologie Microbienne UMR5557, 69622, Villeurbanne Cedex, France
| | - Katharina Pawlowski
- Department of Ecology, Environment and Plant Sciences, Lilla Frescati, Stockholm University, 106 91, Stockholm, Sweden
| | - Alison M. Berry
- Department of Plant Sciences, University of California Davis, Davis, California, 95616, United States of America
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39
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Kim JS, Lee KC, Kim DS, Ko SH, Jung MY, Rhee SK, Lee JS. Pyrosequencing analysis of a bacterial community associated with lava-formed soil from the Gotjawal forest in Jeju, Korea. Microbiologyopen 2015; 4:301-312. [PMID: 25604185 PMCID: PMC4398510 DOI: 10.1002/mbo3.238] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 12/04/2014] [Accepted: 12/12/2014] [Indexed: 02/01/2023] Open
Abstract
In this study, we analyzed the bacterial diversity in soils collected from Gyorae Gotjawal forest, where globally unique topography, geology, and ecological features support a forest grown on basalt flows from 110,000 to 120,000 years ago and 40,000 to 50,000 years ago. The soils at the site are fertile, with rocky areas, and are home to endangered species of plants and animals. Rainwater penetrates to the groundwater aquifer, which is composed of 34% organic matter containing rare types of soil and no soil profile. We determined the bacterial community composition using 116,475 reads from a 454-pyrosequencing analysis. This dataset included 12,621 operational taxonomic units at 3% dissimilarity, distributed among the following groups: Proteobacteria (56.2%) with 45.7% of α-Proteobacteria, Actinobacteria (25%), Acidobacteria (10.9%), Chloroflexi (2.4%), and Bacteroidetes (0.9%). In addition, 16S rRNA gene sequences were amplified using polymerase chain reaction and domain-specific primers to construct a clone library based on 142 bacterial clones. These clones were affiliated with the following groups: Proteobacteria (56%) with 51% of α-Proteobacteria, Acidobacteria (7.8%), Actinobacteria (17.6%), Chloroflexi (2.1%), Bacilli (1.4%), Cyanobacteria (2.8%), and Planctomycetes (1.4%). Within the phylum Proteobacteria, 56 of 80 clones were tentatively identified as 12 unclassified genera. Several new genera and a new family were discovered within the Actinobacteria clones. Results from 454-pyrosequencing revealed that 57% and 34% of the sequences belonged to undescribed genera and families, respectively. The characteristics of Gotjawal soil, which are determined by lava morphology, vegetation, and groundwater penetration, might be reflected in the bacterial community composition.
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Affiliation(s)
- Jong-Shik Kim
- Gyeongbuk Institute for Marine Bioindustry, Uljin, 767-813, Korea
| | - Keun Chul Lee
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, Korea
| | - Dae-Shin Kim
- Research Institute for Hallasan, Jeju Special Self-Governing Province, 690-816, Korea
| | - Suk-Hyung Ko
- Research Institute for Hallasan, Jeju Special Self-Governing Province, 690-816, Korea
| | - Man-Young Jung
- Department of Microbiology, Chungbuk National University, Cheongju, 361-763, Korea
| | - Sung-Keun Rhee
- Department of Microbiology, Chungbuk National University, Cheongju, 361-763, Korea
| | - Jung-Sook Lee
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-806, Korea
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40
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Epelde L, Lanzén A, Blanco F, Urich T, Garbisu C. Adaptation of soil microbial community structure and function to chronic metal contamination at an abandoned Pb-Zn mine. FEMS Microbiol Ecol 2014; 91:1-11. [PMID: 25764532 DOI: 10.1093/femsec/fiu007] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Toxicity of metals released from mine tailings may cause severe damage to ecosystems. A diversity of microorganisms, however, have successfully adapted to such sites. In this study, our objective was to advance the understanding of the indigenous microbial communities of mining-impacted soils. To this end, a metatranscriptomic approach was used to study a heavily metal-contaminated site along a metal concentration gradient (up to 3220 000 and 97 000 mg kg(-1) of Cd, Pb and Zn, respectively) resulting from previous mining. Metal concentration, soil pH and amount of clay were the most important factors determining the structure of soil microbial communities. Interestingly, evenness of the microbial communities, but not its richness, increased with contamination level. Taxa with high metabolic plasticity like Ktedonobacteria and Chloroflexi were found with higher relative abundance in more contaminated samples. However, several taxa belonging to the phyla Actinobacteria and Acidobacteria followed opposite trends in relation to metal pollution. Besides, functional transcripts related to transposition or transfer of genetic material and membrane transport, potentially involved in metal resistance mechanisms, had a higher expression in more contaminated samples. Our results provide an insight into microbial communities in long-term metal-contaminated environments and how they contrast to nearby sites with lower contamination.
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Affiliation(s)
- Lur Epelde
- NEIKER-Tecnalia, Department of Ecology and Natural Resources, Soil Microbial Ecology Group, c/ Berreaga 1, E-48160 Derio, Spain
| | - Anders Lanzén
- NEIKER-Tecnalia, Department of Ecology and Natural Resources, Soil Microbial Ecology Group, c/ Berreaga 1, E-48160 Derio, Spain
| | - Fernando Blanco
- NEIKER-Tecnalia, Department of Ecology and Natural Resources, Soil Microbial Ecology Group, c/ Berreaga 1, E-48160 Derio, Spain
| | - Tim Urich
- Department of Ecogenomics and Systems Biology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Carlos Garbisu
- NEIKER-Tecnalia, Department of Ecology and Natural Resources, Soil Microbial Ecology Group, c/ Berreaga 1, E-48160 Derio, Spain
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41
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Berlemont R, Allison SD, Weihe C, Lu Y, Brodie EL, Martiny JBH, Martiny AC. Cellulolytic potential under environmental changes in microbial communities from grassland litter. Front Microbiol 2014; 5:639. [PMID: 25505459 PMCID: PMC4243572 DOI: 10.3389/fmicb.2014.00639] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 11/06/2014] [Indexed: 12/02/2022] Open
Abstract
In many ecosystems, global changes are likely to profoundly affect microorganisms. In Southern California, changes in precipitation and nitrogen deposition may influence the composition and functional potential of microbial communities and their resulting ability to degrade plant material. To test whether such environmental changes impact the distribution of functional groups involved in leaf litter degradation, we determined how the genomic diversity of microbial communities in a semi-arid grassland ecosystem changed under reduced precipitation or increased N deposition. We monitored communities seasonally over a period of 2 years to place environmental change responses into the context of natural variation. Fungal and bacterial communities displayed strong seasonal patterns, Fungi being mostly detected during the dry season whereas Bacteria were common during wet periods. Most putative cellulose degraders were associated with 33 bacterial genera and predicted to constitute 18% of the microbial community. Precipitation reduction reduced bacterial abundance and cellulolytic potential whereas nitrogen addition did not affect the cellulolytic potential of the microbial community. Finally, we detected a strong correlation between the frequencies of genera of putative cellulose degraders and cellulase genes. Thus, microbial taxonomic composition was predictive of cellulolytic potential. This work provides a framework for how environmental changes affect microorganisms responsible for plant litter deconstruction.
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Affiliation(s)
- Renaud Berlemont
- Department of Earth System Science, University of California, IrvineIrvine, CA, USA
- Department of Biological Science, California State UniversityLong Beach, CA, USA
| | - Steven D. Allison
- Department of Earth System Science, University of California, IrvineIrvine, CA, USA
- Department of Ecology and Evolutionary Biology, University of California, IrvineIrvine, CA, USA
| | - Claudia Weihe
- Department of Ecology and Evolutionary Biology, University of California, IrvineIrvine, CA, USA
| | - Ying Lu
- Department of Ecology and Evolutionary Biology, University of California, IrvineIrvine, CA, USA
| | - Eoin L. Brodie
- Ecology Department, Earth Sciences Division, Lawrence Berkeley National LaboratoryBerkeley, CA, USA
- Department of Environmental Science, Policy and Management, University of CaliforniaBerkeley, CA, USA
| | - Jennifer B. H. Martiny
- Department of Ecology and Evolutionary Biology, University of California, IrvineIrvine, CA, USA
| | - Adam C. Martiny
- Department of Earth System Science, University of California, IrvineIrvine, CA, USA
- Department of Ecology and Evolutionary Biology, University of California, IrvineIrvine, CA, USA
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42
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Sen A, Daubin V, Abrouk D, Gifford I, Berry AM, Normand P. Phylogeny of the class Actinobacteria revisited in the light of complete genomes. The orders ‘Frankiales’ and Micrococcales should be split into coherent entities: proposal of Frankiales ord. nov., Geodermatophilales ord. nov., Acidothermales ord. nov. and Nakamurellales ord. nov. Int J Syst Evol Microbiol 2014; 64:3821-3832. [DOI: 10.1099/ijs.0.063966-0] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The phylogeny of the class
Actinobacteria
remains controversial, essentially because it is very sensitive to the choice of dataset and phylogenetic methods. We used a test proposed recently, based on complete genome data, which chooses among candidate species phylogenies based on the number of lateral gene transfers (LGT) needed to explain the diversity of histories among gene trees for a set of genomes. We used 100 completely sequenced genomes representing 35 families and 17 orders of the class
Actinobacteria
and evaluated eight different hypotheses for their phylogeny, including one based on a concatenate of 54 conserved proteins present in single copy in all these genomes, trees based on 16S and 23S rRNA gene sequences or their concatenation, and a tree based on the concatenation of MLSA genes (encoding AtpI, GyrA, FtsZ, SecA and DnaK). We used Prunier to infer the number of LGT in 579 proteins (different from those used to build the concatenated tree) present in at least 70 species, using the different hypothetical species trees as references. The best tree, with the lowest number of lateral transfers, was the one based on the concatenation of 54 proteins. In that tree, the orders
Bifidobacteriales
,
Coriobacteriales
, ‘Coryneb
acteriales’, ‘Micromonosporales’, ‘Propionibacteriales’, ‘Pseudonocardiales’, Streptomycetales and ‘Streptosporangiales’ were recovered while the orders ‘Frankiales’ and
Micrococcales
were not. It is thus proposed that the order ‘Frankiales’, which has an effectively but not validly published name, be split into Frankiales ord. nov. (type family
Frankiaceae
), Geodermatophilales ord. nov. (
Geodermatophilaceae
), Acidothermales ord. nov. (
Acidothermaceae
) and Nakamurellales ord. nov. (
Nakamurellaceae
). The order
Micrococcales
should also be split into
Micrococcales
(genera
Kocuria
,
Rothia
,
Micrococcus
,
Arthrobacter
,
Tropheryma
,
Microbacterium
,
Leifsonia
and
Clavibacter
), Cellulomonales (
Beutenbergia
,
Cellulomonas
,
Xylanimonas
,
Jonesia
and
Sanguibacter
) and Brachybacteriales (
Brachybacterium
) but the formal proposal for this will have to wait until more genomes become available for a significant proportion of strains in this order.
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Affiliation(s)
- Arnab Sen
- NBU Bioinformatics Facility, Department of Botany, University of North Bengal, Siliguri, 734013, India
| | - Vincent Daubin
- Biométrie et Biologie Evolutive, Centre National de la Recherche Scientifique UMR 5558, Université Lyon I, Université Lyon, Villeurbanne, France
| | - Danis Abrouk
- Ecologie Microbienne, Centre National de la Recherche Scientifique UMR 5557, Université Lyon I, Université Lyon, Villeurbanne, France
| | - Isaac Gifford
- Department of Plant Sciences, University of California, One Shields Avenue, Davis, CA 95616, USA
| | - Alison M. Berry
- Department of Plant Sciences, University of California, One Shields Avenue, Davis, CA 95616, USA
| | - Philippe Normand
- Ecologie Microbienne, Centre National de la Recherche Scientifique UMR 5557, Université Lyon I, Université Lyon, Villeurbanne, France
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43
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Carbonetto B, Rascovan N, Álvarez R, Mentaberry A, Vázquez MP. Structure, composition and metagenomic profile of soil microbiomes associated to agricultural land use and tillage systems in Argentine Pampas. PLoS One 2014; 9:e99949. [PMID: 24923965 PMCID: PMC4055693 DOI: 10.1371/journal.pone.0099949] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 05/20/2014] [Indexed: 12/12/2022] Open
Abstract
Agriculture is facing a major challenge nowadays: to increase crop production for food and energy while preserving ecosystem functioning and soil quality. Argentine Pampas is one of the main world producers of crops and one of the main adopters of conservation agriculture. Changes in soil chemical and physical properties of Pampas soils due to different tillage systems have been deeply studied. Still, not much evidence has been reported on the effects of agricultural practices on Pampas soil microbiomes. The aim of our study was to investigate the effects of agricultural land use on community structure, composition and metabolic profiles on soil microbiomes of Argentine Pampas. We also compared the effects associated to conventional practices with the effects of no-tillage systems. Our results confirmed the impact on microbiome structure and composition due to agricultural practices. The phyla Verrucomicrobia, Plactomycetes, Actinobacteria, and Chloroflexi were more abundant in non cultivated soils while Gemmatimonadetes, Nitrospirae and WS3 were more abundant in cultivated soils. Effects on metabolic metagenomic profiles were also observed. The relative abundance of genes assigned to transcription, protein modification, nucleotide transport and metabolism, wall and membrane biogenesis and intracellular trafficking and secretion were higher in cultivated fertilized soils than in non cultivated soils. We also observed significant differences in microbiome structure and taxonomic composition between soils under conventional and no- tillage systems. Overall, our results suggest that agronomical land use and the type of tillage system have induced microbiomes to shift their life-history strategies. Microbiomes of cultivated fertilized soils (i.e. higher nutrient amendment) presented tendencies to copiotrophy while microbiomes of non cultivated homogenous soils appeared to have a more oligotrophic life-style. Additionally, we propose that conventional tillage systems may promote copiotrophy more than no-tillage systems by decreasing soil organic matter stability and therefore increasing nutrient availability.
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Affiliation(s)
- Belén Carbonetto
- Instituto de Agrobiotecnología de Rosario (INDEAR), Predio CCT Rosario, Santa Fe, Argentina
- * E-mail: (MPV); (BC)
| | - Nicolás Rascovan
- Instituto de Agrobiotecnología de Rosario (INDEAR), Predio CCT Rosario, Santa Fe, Argentina
| | - Roberto Álvarez
- Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Alejandro Mentaberry
- Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Martin P. Vázquez
- Instituto de Agrobiotecnología de Rosario (INDEAR), Predio CCT Rosario, Santa Fe, Argentina
- * E-mail: (MPV); (BC)
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44
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Wang J, Pritchard JR, Kreitmann L, Montpetit A, Behr MA. Disruption of Mycobacterium avium subsp. paratuberculosis-specific genes impairs in vivo fitness. BMC Genomics 2014; 15:415. [PMID: 24885784 PMCID: PMC4058006 DOI: 10.1186/1471-2164-15-415] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Accepted: 05/27/2014] [Indexed: 01/08/2023] Open
Abstract
Background Mycobacterium avium subsp. paratuberculosis (MAP) is an obligate intracellular pathogen that infects many ruminant species. The acquisition of foreign genes via horizontal gene transfer has been postulated to contribute to its pathogenesis, as these genetic elements are absent from its putative ancestor, M. avium subsp. hominissuis (MAH), an environmental organism with lesser pathogenicity. In this study, high-throughput sequencing of MAP transposon libraries were analyzed to qualitatively and quantitatively determine the contribution of individual genes to bacterial survival during infection. Results Out of 52384 TA dinucleotides present in the MAP K-10 genome, 12607 had a MycoMarT7 transposon in the input pool, interrupting 2443 of the 4350 genes in the MAP genome (56%). Of 96 genes situated in MAP-specific genomic islands, 82 were disrupted in the input pool, indicating that MAP-specific genomic regions are dispensable for in vitro growth (odds ratio = 0.21). Following 5 independent in vivo infections with this pool of mutants, the correlation between output pools was high for 4 of 5 (R = 0.49 to 0.61) enabling us to define genes whose disruption reproducibly reduced bacterial fitness in vivo. At three different thresholds for reduced fitness in vivo, MAP-specific genes were over-represented in the list of predicted essential genes. We also identified additional genes that were severely depleted after infection, and several of them have orthologues that are essential genes in M. tuberculosis. Conclusions This work indicates that the genetic elements required for the in vivo survival of MAP represent a combination of conserved mycobacterial virulence genes and MAP-specific genes acquired via horizontal gene transfer. In addition, the in vitro and in vivo essential genes identified in this study may be further characterized to offer a better understanding of MAP pathogenesis, and potentially contribute to the discovery of novel therapeutic and vaccine targets. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-415) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | - Marcel A Behr
- Department of Microbiology and Immunology, McGill University, 3775 University Street, Montreal, QC H3A 2B4, Canada.
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45
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Blumer-Schuette SE, Brown SD, Sander KB, Bayer EA, Kataeva I, Zurawski JV, Conway JM, Adams MWW, Kelly RM. Thermophilic lignocellulose deconstruction. FEMS Microbiol Rev 2014; 38:393-448. [DOI: 10.1111/1574-6976.12044] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 08/20/2013] [Accepted: 08/28/2013] [Indexed: 11/28/2022] Open
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46
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Chandra G, Chater KF. Developmental biology of Streptomyces from the perspective of 100 actinobacterial genome sequences. FEMS Microbiol Rev 2014; 38:345-79. [PMID: 24164321 PMCID: PMC4255298 DOI: 10.1111/1574-6976.12047] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 08/06/2013] [Accepted: 08/20/2013] [Indexed: 12/22/2022] Open
Abstract
To illuminate the evolution and mechanisms of actinobacterial complexity, we evaluate the distribution and origins of known Streptomyces developmental genes and the developmental significance of actinobacteria-specific genes. As an aid, we developed the Actinoblast database of reciprocal blastp best hits between the Streptomyces coelicolor genome and more than 100 other actinobacterial genomes (http://streptomyces.org.uk/actinoblast/). We suggest that the emergence of morphological complexity was underpinned by special features of early actinobacteria, such as polar growth and the coupled participation of regulatory Wbl proteins and the redox-protecting thiol mycothiol in transducing a transient nitric oxide signal generated during physiologically stressful growth transitions. It seems that some cell growth and division proteins of early actinobacteria have acquired greater importance for sporulation of complex actinobacteria than for mycelial growth, in which septa are infrequent and not associated with complete cell separation. The acquisition of extracellular proteins with structural roles, a highly regulated extracellular protease cascade, and additional regulatory genes allowed early actinobacterial stationary phase processes to be redeployed in the emergence of aerial hyphae from mycelial mats and in the formation of spore chains. These extracellular proteins may have contributed to speciation. Simpler members of morphologically diverse clades have lost some developmental genes.
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47
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Campos E, Negro Alvarez MJ, Sabarís di Lorenzo G, Gonzalez S, Rorig M, Talia P, Grasso DH, Sáez F, Manzanares Secades P, Ballesteros Perdices M, Cataldi AA. Purification and characterization of a GH43 β-xylosidase from Enterobacter sp. identified and cloned from forest soil bacteria. Microbiol Res 2014; 169:213-20. [DOI: 10.1016/j.micres.2013.06.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Revised: 06/10/2013] [Accepted: 06/11/2013] [Indexed: 10/26/2022]
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48
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Trame CB, Chang Y, Axelrod HL, Eberhardt RY, Coggill P, Punta M, Rawlings ND. New mini- zincin structures provide a minimal scaffold for members of this metallopeptidase superfamily. BMC Bioinformatics 2014; 15:1. [PMID: 24383880 PMCID: PMC3890501 DOI: 10.1186/1471-2105-15-1] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 12/17/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The Acel_2062 protein from Acidothermus cellulolyticus is a protein of unknown function. Initial sequence analysis predicted that it was a metallopeptidase from the presence of a motif conserved amongst the Asp-zincins, which are peptidases that contain a single, catalytic zinc ion ligated by the histidines and aspartic acid within the motif (HEXXHXXGXXD). The Acel_2062 protein was chosen by the Joint Center for Structural Genomics for crystal structure determination to explore novel protein sequence space and structure-based function annotation. RESULTS The crystal structure confirmed that the Acel_2062 protein consisted of a single, zincin-like metallopeptidase-like domain. The Met-turn, a structural feature thought to be important for a Met-zincin because it stabilizes the active site, is absent, and its stabilizing role may have been conferred to the C-terminal Tyr113. In our crystallographic model there are two molecules in the asymmetric unit and from size-exclusion chromatography, the protein dimerizes in solution. A water molecule is present in the putative zinc-binding site in one monomer, which is replaced by one of two observed conformations of His95 in the other. CONCLUSIONS The Acel_2062 protein is structurally related to the zincins. It contains the minimum structural features of a member of this protein superfamily, and can be described as a "mini- zincin". There is a striking parallel with the structure of a mini-Glu-zincin, which represents the minimum structure of a Glu-zincin (a metallopeptidase in which the third zinc ligand is a glutamic acid). Rather than being an ancestral state, phylogenetic analysis suggests that the mini-zincins are derived from larger proteins.
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Affiliation(s)
| | | | | | | | | | | | - Neil D Rawlings
- Wellcome Trust Sanger Institute, Hinxton, Cambridgeshire, CB10 1SA, UK.
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49
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Reconstructed ancestral Myo-inositol-3-phosphate synthases indicate that ancestors of the Thermococcales and Thermotoga species were more thermophilic than their descendants. PLoS One 2013; 8:e84300. [PMID: 24391933 PMCID: PMC3877268 DOI: 10.1371/journal.pone.0084300] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 11/19/2013] [Indexed: 01/06/2023] Open
Abstract
The bacterial genomes of Thermotoga species show evidence of significant interdomain horizontal gene transfer from the Archaea. Members of this genus acquired many genes from the Thermococcales, which grow at higher temperatures than Thermotoga species. In order to study the functional history of an interdomain horizontally acquired gene we used ancestral sequence reconstruction to examine the thermal characteristics of reconstructed ancestral proteins of the Thermotoga lineage and its archaeal donors. Several ancestral sequence reconstruction methods were used to determine the possible sequences of the ancestral Thermotoga and Archaea myo-inositol-3-phosphate synthase (MIPS). These sequences were predicted to be more thermostable than the extant proteins using an established sequence composition method. We verified these computational predictions by measuring the activities and thermostabilities of purified proteins from the Thermotoga and the Thermococcales species, and eight ancestral reconstructed proteins. We found that the ancestral proteins from both the archaeal donor and the Thermotoga most recent common ancestor recipient were more thermostable than their descendants. We show that there is a correlation between the thermostability of MIPS protein and the optimal growth temperature (OGT) of its host, which suggests that the OGT of the ancestors of these species of Archaea and the Thermotoga grew at higher OGTs than their descendants.
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Samant S, Amann RI, Hahn D. Evaluation of the 23S rRNA gene as target for qPCR based quantification of Frankia in soils. Syst Appl Microbiol 2013; 37:229-34. [PMID: 24315016 DOI: 10.1016/j.syapm.2013.11.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 11/08/2013] [Indexed: 12/30/2022]
Abstract
The 23S rRNA gene was evaluated as target for the development of Sybr Green-based quantitative PCR (qPCR) for the analysis of nitrogen-fixing members of the genus Frankia or subgroups of these in soil. A qPCR with a primer combination targeting all nitrogen-fixing frankiae (clusters 1, 2 and 3) resulted in numbers similar to those obtained with a previously developed qPCR using nifH gene sequences, both with respect to introduced and indigenous Frankia populations. Primer combinations more specifically targeting three subgroups of the Alnus host infection group (cluster 1) or members of the Elaeagnus host infection group (cluster 3) were specific for introduced strains of the target group, with numbers corresponding to those obtained by quantification of nitrogen-fixing frankiae with both the 23S rRNA and nifH genes as target. Method verification on indigenous Frankia populations in soils, i.e. in depth profiles from four sites at an Alnus glutinosa stand, revealed declining numbers in the depth profiles, with similar abundance of all nitrogen-fixing frankiae independent of 23S rRNA or nifH gene targets, and corresponding numbers of one group of frankiae of the Alnus host infection only, with no detections of frankiae representing the Elaeagnus, Casuarina, or a second subgroup of the Alnus host infection groups.
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Affiliation(s)
- Suvidha Samant
- Texas State University, Department of Biology, 601 University Drive, San Marcos, TX 78666, USA
| | - Rudolf I Amann
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, D-28359 Bremen, Germany
| | - Dittmar Hahn
- Texas State University, Department of Biology, 601 University Drive, San Marcos, TX 78666, USA.
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