1
|
Lartey I, Benucci GMN, Marsh TL, Bonito GM, Melakeberhan H. Characterizing microbial communities associated with northern root-knot nematode ( Meloidogyne hapla) occurrence and soil health. Front Microbiol 2023; 14:1267008. [PMID: 38029134 PMCID: PMC10667709 DOI: 10.3389/fmicb.2023.1267008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 10/17/2023] [Indexed: 12/01/2023] Open
Abstract
The northern root-knot nematode (Meloidogyne hapla) causes extensive damage to agricultural crops globally. In addition, M. hapla populations with no known genetic or morphological differences exhibit parasitic variability (PV) or reproductive potential based on soil type. However, why M. hapla populations from mineral soil with degraded soil health conditions have a higher PV than populations from muck soil is unknown. To improve our understanding of soil bio-physicochemical conditions in the environment where M. hapla populations exhibited PV, this study characterized the soil microbial community and core- and indicator-species structure associated with M. hapla occurrence and soil health conditions in 15 Michigan mineral and muck vegetable production fields. Bacterial and fungal communities in soils from where nematodes were isolated were characterized with high throughput sequencing of 16S and internal transcribed spacer (ITS) rDNA. Our results showed that M. hapla-infested, as well as disturbed and degraded muck fields, had lower bacterial diversity (observed richness and Shannon) compared to corresponding mineral soil fields or non-infested mineral fields. Bacterial and fungal community abundance varied by soil group, soil health conditions, and/or M. hapla occurrence. A core microbial community was found to consist of 39 bacterial and 44 fungal sub-operational taxonomic units (OTUs) across all fields. In addition, 25 bacteria were resolved as indicator OTUs associated with M. hapla presence or absence, and 1,065 bacteria as indicator OTUs associated with soil health conditions. Out of the 1,065 bacterial OTUs, 73.9% indicated stable soil health, 8.4% disturbed, and 0.4% degraded condition; no indicators were common to the three categories. Collectively, these results provide a foundation for an in-depth understanding of the environment where M. hapla exists and conditions associated with parasitic variability.
Collapse
Affiliation(s)
- Isaac Lartey
- Agricultural Nematology Laboratory, Department of Horticulture, Michigan State University, East Lansing, MI, United States
| | - Gian M. N. Benucci
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, United States
| | - Terence L. Marsh
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, United States
| | - Gregory M. Bonito
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, United States
| | - Haddish Melakeberhan
- Agricultural Nematology Laboratory, Department of Horticulture, Michigan State University, East Lansing, MI, United States
| |
Collapse
|
2
|
Sun W, Shahrajabian MH. The Application of Arbuscular Mycorrhizal Fungi as Microbial Biostimulant, Sustainable Approaches in Modern Agriculture. PLANTS (BASEL, SWITZERLAND) 2023; 12:3101. [PMID: 37687348 PMCID: PMC10490045 DOI: 10.3390/plants12173101] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/16/2023] [Accepted: 08/24/2023] [Indexed: 09/10/2023]
Abstract
Biostimulant application can be considered an effective, practical, and sustainable nutritional crop supplementation and may lessen the environmental problems related to excessive fertilization. Biostimulants provide beneficial properties to plants by increasing plant metabolism, which promotes crop yield and improves the quality of crops; protecting plants against environmental stresses such as water shortage, soil salinization, and exposure to sub-optimal growth temperatures; and promoting plant growth via higher nutrient uptake. Other important benefits include promoting soil enzymatic and microbial activities, changing the architecture of roots, increasing the solubility and mobility of micronutrients, and enhancing the fertility of the soil, predominantly by nurturing the development of complementary soil microbes. Biostimulants are classified as microbial, such as arbuscular mycorrhizae fungi (AMF), plant-growth-promoting rhizobacteria (PGPR), non-pathogenic fungi, protozoa, and nematodes, or non-microbial, such as seaweed extract, phosphite, humic acid, other inorganic salts, chitin and chitosan derivatives, protein hydrolysates and free amino acids, and complex organic materials. Arbuscular mycorrhizal fungi are among the most prominent microbial biostimulants and have an important role in cultivating better, healthier, and more functional foods in sustainable agriculture. AMF assist plant nutrient and water acquisition; enhance plant stress tolerance against salinity, drought, and heavy metals; and reduce soil erosion. AMF are proven to be a sustainable and environmentally friendly source of crop supplements. The current manuscript gives many examples of the potential of biostimulants for the production of different crops. However, further studies are needed to better understand the effectiveness of different biostimulants in sustainable agriculture. The review focuses on how AMF application can overcome nutrient limitations typical of organic systems by improving nutrient availability, uptake, and assimilation, consequently reducing the gap between organic and conventional yields. The aim of this literature review is to survey the impacts of AMF by presenting case studies and successful paradigms in different crops as well as introducing the main mechanisms of action of the different biostimulant products.
Collapse
Affiliation(s)
- Wenli Sun
- Correspondence: ; Tel.: +86-13-4260-83836
| | | |
Collapse
|
3
|
Shen L, Liu Y, Allen MA, Xu B, Wang N, Williams TJ, Wang F, Zhou Y, Liu Q, Cavicchioli R. Linking genomic and physiological characteristics of psychrophilic Arthrobacter to metagenomic data to explain global environmental distribution. MICROBIOME 2021; 9:136. [PMID: 34118971 PMCID: PMC8196931 DOI: 10.1186/s40168-021-01084-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 04/21/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Microorganisms drive critical global biogeochemical cycles and dominate the biomass in Earth's expansive cold biosphere. Determining the genomic traits that enable psychrophiles to grow in cold environments informs about their physiology and adaptive responses. However, defining important genomic traits of psychrophiles has proven difficult, with the ability to extrapolate genomic knowledge to environmental relevance proving even more difficult. RESULTS Here we examined the bacterial genus Arthrobacter and, assisted by genome sequences of new Tibetan Plateau isolates, defined a new clade, Group C, that represents isolates from polar and alpine environments. Group C had a superior ability to grow at -1°C and possessed genome G+C content, amino acid composition, predicted protein stability, and functional capacities (e.g., sulfur metabolism and mycothiol biosynthesis) that distinguished it from non-polar or alpine Group A Arthrobacter. Interrogation of nearly 1000 metagenomes identified an over-representation of Group C in Canadian permafrost communities from a simulated spring-thaw experiment, indicative of niche adaptation, and an under-representation of Group A in all polar and alpine samples, indicative of a general response to environmental temperature. CONCLUSION The findings illustrate a capacity to define genomic markers of specific taxa that potentially have value for environmental monitoring of cold environments, including environmental change arising from anthropogenic impact. More broadly, the study illustrates the challenges involved in extrapolating from genomic and physiological data to an environmental setting. Video Abstract.
Collapse
Affiliation(s)
- Liang Shen
- State Key Laboratory of Tibetan Plateau Earth System and Resources Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Yongqin Liu
- State Key Laboratory of Tibetan Plateau Earth System and Resources Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China.
- Center for the Pan-third Pole Environment, Lanzhou University, Lanzhou, 730000, China.
| | - Michelle A Allen
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Baiqing Xu
- State Key Laboratory of Tibetan Plateau Earth System and Resources Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Ninglian Wang
- College of Urban and Environmental Science, Northwest University, Xian, 710069, China
| | - Timothy J Williams
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Feng Wang
- State Key Laboratory of Tibetan Plateau Earth System and Resources Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yuguang Zhou
- China General Microbiological Culture Collection Center (CGMCC), Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Qing Liu
- China General Microbiological Culture Collection Center (CGMCC), Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Ricardo Cavicchioli
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, 2052, Australia.
| |
Collapse
|
4
|
Leung PM, Bay SK, Meier DV, Chiri E, Cowan DA, Gillor O, Woebken D, Greening C. Energetic Basis of Microbial Growth and Persistence in Desert Ecosystems. mSystems 2020; 5:e00495-19. [PMID: 32291352 PMCID: PMC7159902 DOI: 10.1128/msystems.00495-19] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microbial life is surprisingly abundant and diverse in global desert ecosystems. In these environments, microorganisms endure a multitude of physicochemical stresses, including low water potential, carbon and nitrogen starvation, and extreme temperatures. In this review, we summarize our current understanding of the energetic mechanisms and trophic dynamics that underpin microbial function in desert ecosystems. Accumulating evidence suggests that dormancy is a common strategy that facilitates microbial survival in response to water and carbon limitation. Whereas photoautotrophs are restricted to specific niches in extreme deserts, metabolically versatile heterotrophs persist even in the hyper-arid topsoils of the Atacama Desert and Antarctica. At least three distinct strategies appear to allow such microorganisms to conserve energy in these oligotrophic environments: degradation of organic energy reserves, rhodopsin- and bacteriochlorophyll-dependent light harvesting, and oxidation of the atmospheric trace gases hydrogen and carbon monoxide. In turn, these principles are relevant for understanding the composition, functionality, and resilience of desert ecosystems, as well as predicting responses to the growing problem of desertification.
Collapse
Affiliation(s)
- Pok Man Leung
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, Victoria, Australia
| | - Sean K Bay
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, Victoria, Australia
| | - Dimitri V Meier
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Eleonora Chiri
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, Victoria, Australia
| | - Don A Cowan
- Centre for Microbial Ecology and Genomics, University of Pretoria, Hatfield, Pretoria, South Africa
| | - Osnat Gillor
- Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sde Boker, Israel
| | - Dagmar Woebken
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Chris Greening
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, Victoria, Australia
| |
Collapse
|
5
|
Pathak A, Jaswal R, Chauhan A. Genomic Characterization of a Mercury Resistant Arthrobacter sp. H-02-3 Reveals the Presence of Heavy Metal and Antibiotic Resistance Determinants. Front Microbiol 2020; 10:3039. [PMID: 32010097 PMCID: PMC6978705 DOI: 10.3389/fmicb.2019.03039] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 12/17/2019] [Indexed: 11/18/2022] Open
Abstract
Nuclear production and industrial activities led to widespread contamination of the Department of Energy (DOE) managed Savannah River Site (SRS), located in South Carolina, United States. The H-02 wetland system was constructed in 2007 for the treatment of industrial and storm water runoff from the SRS Tritium Facility. Albeit at low levels, mercury (Hg) has been detected in the soils of the H-02 wetland ecosystem. In anoxic sediments, Hg is typically methylated by anaerobic microbiota, forming the highly neurotoxic methylmercury (MeHg), which biomagnifies across food webs. However, in surficial oxic wetland soils, microbially mediated demethylation and/or volatilization processes can transform Hg2+ into the less toxic Hg0 form which is released into the atmosphere, thus circumventing MeHg formation. To obtain a deeper understanding on bacterial Hg volatilization, a robust Hg-resistant (HgR) bacteria, called as strain H-02-3 was isolated from the H-02 soils. A draft genome sequence of this strain was obtained at a coverage of 700×, which assembled in 44 contigs with an N50 of 171,569 bp. The genomic size of the strain H-02-3 was 4,708,612 bp with a total number of 4,240 genes; phylogenomic analysis revealed the strain as an Arthrobacter species. Comparative genomics revealed the presence of 1100 unique genes in strain H-02-3, representing 26.7% of the total genome; many identified previously as metal resistance genes (MRGs). Specific to Hg-cycling, the presence of mercuric ion reductase (merA), the organomercurial lyase (merB), and the mercuric resistance operon regulatory protein, were identified. By inference, it can be proposed that the organomercurial lyase facilitates the demethylation of MeHg into Hg2+ which is then reduced to Hg0 by MerA in strain H-02-3. Furthermore, gene prediction using resistome analysis of strain H-02-3 revealed the presence of several antibiotic resistance genes (ARGs), that statistically correlated with the presence of metal resistant genes (MRGs), suggesting co-occurrence patterns of MRGs and ARGs in the strain. Overall, this study delineates environmentally beneficial traits that likely facilitates survival of Arthrobacter sp. H-02-3 within the H-02 wetland soil. Finally, this study also highlights the largely ignored public health risk associated with the co-development of ARGs and MRGs in bacteria native to historically contaminated soils.
Collapse
Affiliation(s)
- Ashish Pathak
- Environmental Biotechnology Laboratory, School of the Environment, FSH Science Research Center, Florida A&M University, Tallahassee, FL, United States
| | - Rajneesh Jaswal
- Environmental Biotechnology Laboratory, School of the Environment, FSH Science Research Center, Florida A&M University, Tallahassee, FL, United States
| | - Ashvini Chauhan
- Environmental Biotechnology Laboratory, School of the Environment, FSH Science Research Center, Florida A&M University, Tallahassee, FL, United States
| |
Collapse
|
6
|
Colonization of plant roots and enhanced atrazine degradation by a strain of Arthrobacter ureafaciens. Appl Microbiol Biotechnol 2017; 101:6809-6820. [PMID: 28699022 PMCID: PMC5554279 DOI: 10.1007/s00253-017-8405-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 06/10/2017] [Accepted: 06/20/2017] [Indexed: 11/24/2022]
Abstract
Our previous research found that culturable atrazine degraders associated with maize roots were dominated by genetically similar strains of Arthrobacter ureafaciens, suggesting their rhizosphere competence. The present study aimed to assess the root-colonizing capacity of strain A. ureafaciens DnL1-1 and to evaluate consequent root-associated degradation of atrazine. A soil-sand assay and pot experiments provided evidence that A. ureafaciens DnL1-1 competitively colonized roots of maize, wheat, and alfalfa following seed inoculation. Atrazine was not absolutely required but promoted colonization of plant roots by the bacterium. In association with plants, A. ureafaciens DnL1-1 enhanced the degradation of atrazine and strongly reduced accumulation of its dealkylated metabolites. Our results show that after low-level inoculation of seeds, the bacterium A. ureafaciens DnL1-1 can establish root populations sufficient for the rapid degradation of atrazine in soil that makes it a promising bioremediation agent which can be easily applied to large areas of polluted soil. Application of the root-colonizing, atrazine-degrading Arthrobacter bacteria as seed inoculants may be a reliable remediation strategy for soils contaminated with chlorinated s-triazines and their degradation products.
Collapse
|
7
|
Kaliniene L, Šimoliūnas E, Truncaitė L, Zajančkauskaitė A, Nainys J, Kaupinis A, Valius M, Meškys R. Molecular Analysis of Arthrobacter Myovirus vB_ArtM-ArV1: We Blame It on the Tail. J Virol 2017; 91:e00023-17. [PMID: 28122988 PMCID: PMC5375659 DOI: 10.1128/jvi.00023-17] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 01/23/2017] [Indexed: 11/20/2022] Open
Abstract
This is the first report on a myophage that infects Arthrobacter A novel virus, vB_ArtM-ArV1 (ArV1), was isolated from soil using Arthrobacter sp. strain 68b for phage propagation. Transmission electron microscopy showed its resemblance to members of the family Myoviridae: ArV1 has an isometric head (∼74 nm in diameter) and a contractile, nonflexible tail (∼192 nm). Phylogenetic and comparative sequence analyses, however, revealed that ArV1 has more genes in common with phages from the family Siphoviridae than it does with any myovirus characterized to date. The genome of ArV1 is a linear, circularly permuted, double-stranded DNA molecule (71,200 bp) with a GC content of 61.6%. The genome includes 101 open reading frames (ORFs) yet contains no tRNA genes. More than 50% of ArV1 genes encode unique proteins that either have no reliable identity to database entries or have homologues only in Arthrobacter phages, both sipho- and myoviruses. Using bioinformatics approaches, 13 ArV1 structural genes were identified, including those coding for head, tail, tail fiber, and baseplate proteins. A further 6 ArV1 ORFs were annotated as encoding putative structural proteins based on the results of proteomic analysis. Phylogenetic analysis based on the alignment of four conserved virion proteins revealed that Arthrobacter myophages form a discrete clade that seems to occupy a position somewhat intermediate between myo- and siphoviruses. Thus, the data presented here will help to advance our understanding of genetic diversity and evolution of phages that constitute the order CaudoviralesIMPORTANCE Bacteriophages, which likely originated in the early Precambrian Era, represent the most numerous population on the planet. Approximately 95% of known phages are tailed viruses that comprise three families: Podoviridae (with short tails), Siphoviridae (with long noncontractile tails), and Myoviridae (with contractile tails). Based on the current hypothesis, myophages, which may have evolved from siphophages, are thought to have first emerged among Gram-negative bacteria, whereas they emerged only later among Gram-positive bacteria. The results of the molecular characterization of myophage vB_ArtM-ArV1 presented here conform to the aforementioned hypothesis, since, at a glance, bacteriophage vB_ArtM-ArV1 appears to be a siphovirus that possesses a seemingly functional contractile tail. Our work demonstrates that such "chimeric" myophages are of cosmopolitan nature and are likely characteristic of the ecologically important soil bacterial genus Arthrobacter.
Collapse
Affiliation(s)
- Laura Kaliniene
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Centre, Vilnius University, Vilnius, Lithuania
| | - Eugenijus Šimoliūnas
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Centre, Vilnius University, Vilnius, Lithuania
| | - Lidija Truncaitė
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Centre, Vilnius University, Vilnius, Lithuania
| | - Aurelija Zajančkauskaitė
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Centre, Vilnius University, Vilnius, Lithuania
| | - Juozas Nainys
- Department of Eukaryote Gene Engineering, Institute of Biotechnology, Life Sciences Centre, Vilnius University, Vilnius, Lithuania
| | - Algirdas Kaupinis
- Proteomics Centre, Institute of Biochemistry, Life Sciences Centre, Vilnius University, Vilnius, Lithuania
| | - Mindaugas Valius
- Proteomics Centre, Institute of Biochemistry, Life Sciences Centre, Vilnius University, Vilnius, Lithuania
| | - Rolandas Meškys
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Centre, Vilnius University, Vilnius, Lithuania
| |
Collapse
|
8
|
Samad A, Trognitz F, Compant S, Antonielli L, Sessitsch A. Shared and host-specific microbiome diversity and functioning of grapevine and accompanying weed plants. Environ Microbiol 2017; 19:1407-1424. [PMID: 27871147 DOI: 10.1111/1462-2920.13618] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/11/2016] [Accepted: 11/16/2016] [Indexed: 11/30/2022]
Abstract
Weeds and crop plants select their microbiota from the same pool of soil microorganisms, however, the ecology of weed microbiomes is poorly understood. We analysed the microbiomes associated with roots and rhizospheres of grapevine and four weed species (Lamium amplexicaule L., Veronica arvensis L., Lepidium draba L. and Stellaria media L.) growing in proximity in the same vineyard using 16S rRNA gene sequencing. We also isolated and characterized 500 rhizobacteria and root endophytes from L. draba and grapevine. Microbiome data analysis revealed that all plants hosted significantly different microbiomes in the rhizosphere as well as in root compartment, however, differences were more pronounced in the root compartment. The shared microbiome of grapevine and the four weed species contained 145 OTUs (54.2%) in the rhizosphere, but only nine OTUs (13.2%) in the root compartment. Seven OTUs (12.3%) were shared in all plants and compartments. Approximately 56% of the major OTUs (>1%) showed more than 98% identity to bacteria isolated in this study. Moreover, weed-associated bacteria generally showed a higher species richness in the rhizosphere, whereas the root-associated bacteria were more diverse in the perennial plants grapevine and L. draba. Overall, weed isolates showed more plant growth-promoting characteristics compared with grapevine isolates.
Collapse
Affiliation(s)
- Abdul Samad
- AIT Austrian Institute of Technology GmbH, Bioresources Unit, Konrad-Lorenz-Straße 24, Tulln, 3430, Austria
| | - Friederike Trognitz
- AIT Austrian Institute of Technology GmbH, Bioresources Unit, Konrad-Lorenz-Straße 24, Tulln, 3430, Austria
| | - Stéphane Compant
- AIT Austrian Institute of Technology GmbH, Bioresources Unit, Konrad-Lorenz-Straße 24, Tulln, 3430, Austria
| | - Livio Antonielli
- AIT Austrian Institute of Technology GmbH, Bioresources Unit, Konrad-Lorenz-Straße 24, Tulln, 3430, Austria
| | - Angela Sessitsch
- AIT Austrian Institute of Technology GmbH, Bioresources Unit, Konrad-Lorenz-Straße 24, Tulln, 3430, Austria
| |
Collapse
|
9
|
Lee CS, Kim M, Lee C, Yu Z, Lee J. The Microbiota of Recreational Freshwaters and the Implications for Environmental and Public Health. Front Microbiol 2016; 7:1826. [PMID: 27909431 PMCID: PMC5112438 DOI: 10.3389/fmicb.2016.01826] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 10/31/2016] [Indexed: 12/03/2022] Open
Abstract
The microbial communities in recreational freshwaters play important roles in both environmental and public health perspectives. In this study, the bacterial community structure and its associations with freshwater environments were investigated by analyzing the summertime microbiomes of three beach waters in Ohio (East Fork, Delaware, and Madison lakes) together with environmental and microbial water quality parameters. From the swimming season of 2009, 21 water samples were collected from the three freshwater beaches. From the samples, 110,000 quality-checked bacterial 16S rRNA gene sequences were obtained and analyzed, resulting in an observation of 4500 bacterial operational taxonomic units (OTUs). The most abundant bacteria were Mycobacterium and Arthrobacter of the Actinobacteria (33.2%), Exiguobacterium and Paenisporosarcina of the Firmicutes (23.4%), Planktothrix and Synechococcus of the Cyanobacteria (20.8%), and Methylocystis and Polynucleobacter of the Proteobacteria (16.3%). Considerable spatial and temporal variations were observed in the bacterial community of Actinobacteria, Cyanobacteria, and Firmicutes, where the bacterial community structure was greatly influenced by hydrological and weather conditions. The most influential factors were (1) water inflow for Bacteroidia and Clostridia, (2) turbidity for Gammaproteobacteria, (3) precipitation for Bacilli, and (4) temperature and pH for Cyanobacteria. One noticeable microbial interaction in the bacterial community was a significant negative relationship between Cyanobacteria and Bacilli (P < 0.05). Concerning beach water quality, the level of the genetic markers for cyanobacterial toxin (mcyA) was linked to the abundance of Cyanobacteria. In addition, unique distributions of the genera Enterococcus, Staphylococcus, Streptococcus, Bacteroides, Clostridium, Finegoldia, Burkholderia, and Klebsiella, together with a high density of fecal indicator Escherichia coli, were markedly observed in the sample from Madison Lake on July 13, suggesting a distinctly different source of bacterial loading into the lake, possibly fecal contamination. In conclusion, deep sequencing-based microbial community analysis can provide detailed profiles of bacterial communities and information on potential public health risks at freshwater beaches.
Collapse
Affiliation(s)
- Chang Soo Lee
- Division of Environmental Health Sciences, College of Public Health, The Ohio State UniversityColumbus, OH, USA
| | - Minseok Kim
- Department of Animal Sciences, The Ohio State UniversityColumbus, OH, USA
| | - Cheonghoon Lee
- Division of Environmental Health Sciences, College of Public Health, The Ohio State UniversityColumbus, OH, USA
| | - Zhongtang Yu
- Department of Animal Sciences, The Ohio State UniversityColumbus, OH, USA
| | - Jiyoung Lee
- Division of Environmental Health Sciences, College of Public Health, The Ohio State UniversityColumbus, OH, USA
- Department of Food Science and Technology, The Ohio State UniversityColumbus, OH, USA
| |
Collapse
|
10
|
Šimoliūnas E, Kaliniene L, Stasilo M, Truncaitė L, Zajančkauskaitė A, Staniulis J, Nainys J, Kaupinis A, Valius M, Meškys R. Isolation and characterization of vB_ArS-ArV2 - first Arthrobacter sp. infecting bacteriophage with completely sequenced genome. PLoS One 2014; 9:e111230. [PMID: 25333962 PMCID: PMC4205034 DOI: 10.1371/journal.pone.0111230] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 09/26/2014] [Indexed: 02/05/2023] Open
Abstract
This is the first report on a complete genome sequence and biological characterization of the phage that infects Arthrobacter. A novel virus vB_ArS-ArV2 (ArV2) was isolated from soil using Arthrobacter sp. 68b strain for phage propagation. Based on transmission electron microscopy, ArV2 belongs to the family Siphoviridae and has an isometric head (∼63 nm in diameter) with a non-contractile flexible tail (∼194×10 nm) and six short tail fibers. ArV2 possesses a linear, double-stranded DNA genome (37,372 bp) with a G+C content of 62.73%. The genome contains 68 ORFs yet encodes no tRNA genes. A total of 28 ArV2 ORFs have no known functions and lack any reliable database matches. Proteomic analysis led to the experimental identification of 14 virion proteins, including 9 that were predicted by bioinformatics approaches. Comparative phylogenetic analysis, based on the amino acid sequence alignment of conserved proteins, set ArV2 apart from other siphoviruses. The data presented here will help to advance our understanding of Arthrobacter phage population and will extend our knowledge about the interaction between this particular host and its phages.
Collapse
Affiliation(s)
- Eugenijus Šimoliūnas
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius, Lithuania
| | - Laura Kaliniene
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius, Lithuania
| | - Miroslav Stasilo
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius, Lithuania
| | - Lidija Truncaitė
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius, Lithuania
| | - Aurelija Zajančkauskaitė
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius, Lithuania
| | - Juozas Staniulis
- Laboratory of Plant Viruses, Institute of Botany, Nature Research Centre, Vilnius, Lithuania
| | - Juozas Nainys
- Department of Eukaryote Gene Engineering, Institute of Biotechnology, Vilnius University, Vilnius, Lithuania
| | - Algirdas Kaupinis
- Proteomics Centre, Institute of Biochemistry, Vilnius University, Vilnius, Lithuania
| | - Mindaugas Valius
- Proteomics Centre, Institute of Biochemistry, Vilnius University, Vilnius, Lithuania
| | - Rolandas Meškys
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius, Lithuania
| |
Collapse
|
11
|
Ronan E, Yeung CW, Hausner M, Wolfaardt GM. Interspecies interaction extends bacterial survival at solid-air interfaces. BIOFOULING 2013; 29:1087-1096. [PMID: 24041248 DOI: 10.1080/08927014.2013.829820] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Despite the ubiquity of biofilms in natural and man-made environments, research on surface-associated cells has focused primarily on solid-liquid interfaces. This study evaluated the extent to which bacterial cells persist on inanimate solid-air interfaces. The desiccation tolerance of bacterial strains isolated from indoor air, as well as of a test strain (Pseudomonas aeruginosa), was determined at different levels of relative humidity (RH) using the large droplet inoculation method in an aerosol chamber. The cells survived longer at lower (25 and 42%) than at high RH (95%). Four of the seven indoor strains selected for further study showed extended period of survival following deposition as 0.05-0.1 ml of washed culture followed by desiccation, each with different effects on the survival of the test strain, P. aeruginosa. A strain closely related to Arthrobacter species afforded the highest level of protection to the test strain. Even though the desiccation-tolerant strains survived when they were deposited as bioaerosols, the protective role towards the test strain was not observed when the latter was deposited as a bioaerosol. These, which are often-unculturable, bacteria may go undetected during routine monitoring of biofouling, thereby allowing them to act as reservoirs and extending the habitat range of undesired microorganisms.
Collapse
Affiliation(s)
- Evan Ronan
- a Department of Chemistry and Biology , Ryerson University , Toronto , ON , Canada
| | | | | | | |
Collapse
|
12
|
Niewerth H, Schuldes J, Parschat K, Kiefer P, Vorholt JA, Daniel R, Fetzner S. Complete genome sequence and metabolic potential of the quinaldine-degrading bacterium Arthrobacter sp. Rue61a. BMC Genomics 2012; 13:534. [PMID: 23039946 PMCID: PMC3534580 DOI: 10.1186/1471-2164-13-534] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Accepted: 10/01/2012] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Bacteria of the genus Arthrobacter are ubiquitous in soil environments and can be considered as true survivalists. Arthrobacter sp. strain Rue61a is an isolate from sewage sludge able to utilize quinaldine (2-methylquinoline) as sole carbon and energy source. The genome provides insight into the molecular basis of the versatility and robustness of this environmental Arthrobacter strain. RESULTS The genome of Arthrobacter sp. Rue61a consists of a single circular chromosome of 4,736,495 bp with an average G + C content of 62.32%, the circular 231,551-bp plasmid pARUE232, and the linear 112,992-bp plasmid pARUE113 that was already published. Plasmid pARUE232 is proposed to contribute to the resistance of Arthrobacter sp. Rue61a to arsenate and Pb2+, whereas the linear plasmid confers the ability to convert quinaldine to anthranilate. Remarkably, degradation of anthranilate exclusively proceeds via a CoA-thioester pathway. Apart from quinaldine utilization, strain Rue61a has a limited set of aromatic degradation pathways, enabling the utilization of 4-hydroxy-substituted aromatic carboxylic acids, which are characteristic products of lignin depolymerization, via ortho cleavage of protocatechuate. However, 4-hydroxyphenylacetate degradation likely proceeds via meta cleavage of homoprotocatechuate. The genome of strain Rue61a contains numerous genes associated with osmoprotection, and a high number of genes coding for transporters. It encodes a broad spectrum of enzymes for the uptake and utilization of various sugars and organic nitrogen compounds. A. aurescens TC-1 is the closest sequenced relative of strain Rue61a. CONCLUSIONS The genome of Arthrobacter sp. Rue61a reflects the saprophytic lifestyle and nutritional versatility of the organism and a strong adaptive potential to environmental stress. The circular plasmid pARUE232 and the linear plasmid pARUE113 contribute to heavy metal resistance and to the ability to degrade quinaldine, respectively.
Collapse
Affiliation(s)
- Heiko Niewerth
- Institute of Molecular Microbiology and Biotechnology, University of Münster, Corrensstrasse 3, 48149, Münster, Germany
| | - Jörg Schuldes
- Department of Genomic and Applied Microbiology & Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August University Göttingen, 37077, Göttingen, Germany
| | - Katja Parschat
- Institute of Molecular Microbiology and Biotechnology, University of Münster, Corrensstrasse 3, 48149, Münster, Germany
- Present address: Jennewein Biotechnologie GmbH, 53619, Rheinbreitbach, Germany
| | - Patrick Kiefer
- Institute of Microbiology, ETH Zurich, Zurich, Switzerland
| | | | - Rolf Daniel
- Department of Genomic and Applied Microbiology & Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August University Göttingen, 37077, Göttingen, Germany
| | - Susanne Fetzner
- Institute of Molecular Microbiology and Biotechnology, University of Münster, Corrensstrasse 3, 48149, Münster, Germany
| |
Collapse
|
13
|
Li YT, Zhang HH, Sheng HM, An LZ. Cloning, expression and characterization of trehalose-6-phosphate phosphatase from a psychrotrophic bacterium, Arthrobacter strain A3. World J Microbiol Biotechnol 2012; 28:2713-21. [PMID: 22806197 DOI: 10.1007/s11274-012-1082-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2011] [Accepted: 05/14/2012] [Indexed: 11/26/2022]
Abstract
A trehalose-6-phosphate phosphatase (TPP) gene, otsB, from a psychrotrophic bacterium, Arthrobacter strain A3, was identified. The product of this otsB gene is 266 amino acids in length with a calculated molecular weight of 27,873 Da. The protein was expressed in Escherichia coli and purified to apparent homogeneity. The purified recombinant TPP catalyzed the dephosphorylation of trehalose-6-phosphate to form trehalose and showed a broad optimum pH range from 5.0 to 7.5. This enzyme also showed an absolute requirement for Mg(2+) or Co(2+) for catalytic activity. The recombinant TPP had a maximum activity at 30 °C and maintained activity over a temperature range of 4-30 °C. TPP was generally heat-labile, losing 70 % of its activity when subjected to heat treatment at 50 °C for 6 min. Kinetic analysis of the Arthrobacter strain A3 TPP showed ~tenfold lower K (m) values when compared with values derived from other bacterial TPP enzymes. The highest k (cat)/K (m) value was 37.5 mM(-1) s(-1) (repeated three times), which is much higher than values published for mesophilic E. coli TPP, indicating that the Arthrobacter strain A3 TPP possessed excellent catalytic activity at low temperatures. Accordingly, these characteristics suggest that the TPP from the Arthrobacter strain A3 is a new cold-adapted enzyme. In addition, this is the first report characterizing the enzymatic properties of a TPP from a psychrotrophic organism.
Collapse
Affiliation(s)
- Yuan-Ting Li
- Key Laboratory of Arid and Grassland Agroecology of the Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China
| | | | | | | |
Collapse
|
14
|
Stanislauskiene R, Gasparaviciute R, Vaitekunas J, Meskiene R, Rutkiene R, Casaite V, Meskys R. Construction of Escherichia coli-Arthrobacter-Rhodococcus shuttle vectors based on a cryptic plasmid from Arthrobacter rhombi and investigation of their application for functional screening. FEMS Microbiol Lett 2011; 327:78-86. [PMID: 22098420 DOI: 10.1111/j.1574-6968.2011.02462.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 11/14/2011] [Accepted: 11/16/2011] [Indexed: 11/27/2022] Open
Abstract
A cryptic plasmid from Arthrobacter rhombi PRH1, designated as pPRH, was sequenced and characterized. It was 5000 bp in length with a G+C content of 66 mol%. The plasmid pPRH was predicted to encode six putative open reading frames (ORFs), in which ORF2 and ORF3 formed the minimal replicon of plasmid pPRH and shared 55-61% and 60-69% homology, respectively, with the RepA and RepB proteins of reported rhodococcal plasmids. Sequence analysis revealed a typical ColE2-type ori located 45 bp upstream of the gene repA. Sequence and phylogenetic analysis led to the conclusion that pPRH is a representative of a novel group of pAL5000 subfamily of ColE2 family plasmids. Three shuttle vectors pRMU824, pRMU824Km and pRMU824Tc, encoding chloramphenicol resistance, were constructed. The latter two harboured additional antibiotic resistance genes kan and tet, respectively. All vectors successfully replicated in Escherichia coli, Arthrobacter and Rhodococcus spp. The vector pRMU824Km was employed for functional screening of 2-hydroxypyridine catabolism encoding genes from Arthrobacter sp. PY22. Sequence analysis of the cloned 6-kb DNA fragment revealed eight putative ORFs, among which hpyB gene encoded a putative monooxygenase.
Collapse
Affiliation(s)
- Ruta Stanislauskiene
- Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius, Lithuania
| | | | | | | | | | | | | |
Collapse
|
15
|
Wagenknecht M, Meinhardt F. Copy number determination, expression analysis of genes potentially involved in replication, and stability assays of pAL1 – the linear megaplasmid of Arthrobacter nitroguajacolicus Rü61a. Microbiol Res 2011; 166:14-26. [DOI: 10.1016/j.micres.2009.12.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 12/17/2009] [Accepted: 12/30/2009] [Indexed: 10/19/2022]
|
16
|
Zhang H, Li Y, Chen X, Sheng H, An L. Optimization of electroporation conditions for Arthrobacter with plasmid PART2. J Microbiol Methods 2010; 84:114-20. [PMID: 21078345 DOI: 10.1016/j.mimet.2010.11.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 11/05/2010] [Accepted: 11/07/2010] [Indexed: 11/19/2022]
Abstract
A prerequisite for genetic studies of Arthrobacter is a high efficiency transformation system that allows for DNA transfer, transposon mutagenesis, and expression of specific genes. In this study, we develop a detailed electroporation method through a systematic examination of the factors involved in the entire electroporation process. Key features of this procedure, including the addition of penicillin to cells during the early log phase of growth and the presence of 0.5M sorbitol in the electroporation and recovery media, produced the greatest increases in transformation efficiency and consistency of results. The transformation rate also varied depending on the electrical parameters, DNA concentration, and recovery time period. Using optimum conditions, we generally achieved an efficiency of 6.8 × 10(7) transformants per microgram of PART2 for Arthrobacter sp. A3. This protocol was also successfully applied to other Arthrobacter species. Therefore, we conclude that the proposed method is rapid, simple and convenient, which allows a transformation trial to be accomplished in minutes.
Collapse
Affiliation(s)
- Haihong Zhang
- Key Laboratory of Arid and Grassland Agroecology of Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou 730000, People's Republic of China
| | | | | | | | | |
Collapse
|
17
|
Cockell CS, Osinski GR, Banerjee NR, Howard KT, Gilmour I, Watson JS. The microbe-mineral environment and gypsum neogenesis in a weathered polar evaporite. GEOBIOLOGY 2010; 8:293-308. [PMID: 20456500 DOI: 10.1111/j.1472-4669.2010.00240.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Evaporitic deposits are a globally widespread habitat for micro-organisms. The microbe-mineral environment in weathered and remobilized gypsum from exposed mid-Ordovician marine evaporite beds in the polar desert of Devon Island, Nunavut, Canadian High Arctic was examined. The gypsum is characterized by internal green zones of cyanobacterial colonization (dominated by Gloeocapsa/Aphanothece and Chroococcidiopsis spp. morphotypes) and abundant black zones, visible from the surface, that contain pigmented cyanobacteria and fungi. Bioessential elements in the gypsum are primarily provided by allochthonous material from the present-day polar desert. The disruption, uplift and rotation of the evaporite beds by the Haughton meteorite impact 39 Ma have facilitated gypsum weathering and its accessibility as a habitat. No cultured cyanobacteria, bacteria and fungi were halophilic consistent with the expectation that halophily is not required to persist in gypsum habitats. Heterotrophic bacteria from the evaporite were slightly or moderately halotolerant, as were heterotrophs isolated from soil near the gypsum outcrop showing that halotolerance is common in arctic bacteria in this location. Psychrotolerant Arthrobacter species were isolated. No psychrophilic organisms were isolated. Two Arthrobacter isolates from the evaporite were used to mediate gypsum neogenesis in the laboratory, demonstrating a potential role for microbial biomineralization processes in polar environments.
Collapse
Affiliation(s)
- C S Cockell
- Geomicrobiology Research Group, Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR), Open University, Milton Keynes, UK.
| | | | | | | | | | | |
Collapse
|
18
|
Overhage J, Sielker S, Homburg S, Parschat K, Fetzner S. Identification of large linear plasmids in Arthrobacter spp. encoding the degradation of quinaldine to anthranilate. MICROBIOLOGY-SGM 2005; 151:491-500. [PMID: 15699198 DOI: 10.1099/mic.0.27521-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Arthrobacter nitroguajacolicus Rü61a, which utilizes quinaldine as sole source of carbon and energy, was shown to contain a conjugative linear plasmid of approximately 110 kb, named pAL1. It exhibits similarities with other linear plasmids from Actinomycetales in that it has proteins covalently attached to its 5' ends. Southern hybridization with probes for the genes encoding quinaldine 4-oxidase and N-acetylanthranilate amidase indicated that pAL1 contains the gene cluster encoding the degradation of quinaldine to anthranilate. A mutant of strain Rü61a that had lost pAL1 indeed could not convert quinaldine, but was still able to grow on anthranilate. Conjugative transfer of pAL1 to the plasmid-less mutant of strain Rü61a and to Arthrobacter nicotinovorans DSM 420 (pAO1) occurred at frequencies of 5.4x10(-4) and 2.0x10(-4) per recipient, respectively, and conferred the ability to utilize quinaldine. Five other quinaldine-degrading Gram-positive strains were isolated from soil samples; 16S rDNA sequence analysis suggested the closest relationship to different Arthrobacter species. Except for strain K2-29, all isolates contained a pAL1-like linear plasmid carrying genes encoding quinaldine conversion. A 478 bp fragment that on pAL1 represents an intergenic region showed 100 % sequence identity in all isolates harbouring a pAL1-like plasmid, suggesting horizontal dissemination of the linear plasmid among the genus Arthrobacter.
Collapse
Affiliation(s)
- Jörg Overhage
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Corrensstraße 3, D-48149 Münster, Germany
| | - Sonja Sielker
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Corrensstraße 3, D-48149 Münster, Germany
| | - Stefan Homburg
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Corrensstraße 3, D-48149 Münster, Germany
| | - Katja Parschat
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Corrensstraße 3, D-48149 Münster, Germany
| | - Susanne Fetzner
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Corrensstraße 3, D-48149 Münster, Germany
| |
Collapse
|
19
|
Demkina EV, Soina VS, Registan GIE, Zvyagintsev DG. Reproductive resting forms ofArthrobacter globiformis. Microbiology (Reading) 2000. [DOI: 10.1007/bf02756739] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
|
20
|
Cacciari I, Lippi D, Pietrosanti T, Pietrosanti W. Effect of previous growth conditions on starvation survival and endogenous metabolism rate of Arthrobacter fluorescens. J Basic Microbiol 1995. [DOI: 10.1002/jobm.3620350602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
21
|
Kieft TL, Ringelberg DB, White DC. Changes in Ester-Linked Phospholipid Fatty Acid Profiles of Subsurface Bacteria during Starvation and Desiccation in a Porous Medium. Appl Environ Microbiol 1994; 60:3292-9. [PMID: 16349382 PMCID: PMC201801 DOI: 10.1128/aem.60.9.3292-3299.1994] [Citation(s) in RCA: 208] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ester-linked phospholipid fatty acid (PLFA) profiles of a
Pseudomonas aureofaciens
strain and an
Arthrobacter protophormiae
strain, each isolated from a subsurface sediment, were quantified in a starvation experiment in a silica sand porous medium under moist and dry conditions. Washed cells were added to sand microcosms and maintained under saturated conditions or subjected to desiccation by slow drying over a period of 16 days to final water potentials of approximately - 7.5 MPa for the
P. aureofaciens
and - 15 MPa for the
A. protophormiae.
In a third treatment, cells were added to saturated microcosms along with organic nutrients and maintained under saturated conditions. The numbers of culturable cells of both bacterial strains declined to below detection level within 16 days in both the moist and dried nutrient-deprived conditions, while direct counts and total PLFAs remained relatively constant. Both strains of bacteria maintained culturability in the nutrient-amended microcosms. The dried
P. aureofaciens
cells showed changes in PLFA profiles that are typically associated with stressed gram-negative cells, i.e., increased ratios of saturated to unsaturated fatty acids, increased ratios of
trans
- to
cis
-monoenoic fatty acids, and increased ratios of cyclopropyl fatty acids to their monoenoic precursors.
P. aureofaciens
starved under moist conditions showed few changes in PLFA profiles during the 16-day incubation, whereas cells incubated in the presence of nutrients showed decreases in the ratios of both saturated fatty acids to unsaturated fatty acids and cyclopropyl fatty acids to their monoenoic precursors. The PLFA profiles of
A. protophormiae
changed very little in response to either nutrient deprivation or desiccation. Diglyceride fatty acids, which have been proposed to be indicators of dead or lysed cells, remained relatively constant throughout the experiment. Only the
A. protophormiae
desiccated for 16 days showed an increase in the ratio of diglyceride fatty acids to PLFAs. The results of this laboratory experiment can be useful for interpreting PLFA profiles of subsurface communities of microorganisms for the purpose of determining their physiological status.
Collapse
Affiliation(s)
- T L Kieft
- Department of Biology, New Mexico Institute of Mining and Technology, Socorro, New Mexico 87801
| | | | | |
Collapse
|