DOCSLIB.ORG

Oxidative Stress Resistance in Deinococcus Radiodurans†

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Oxidative Stress Resistance in Deinococcus Radiodurans† Downloaded from MICROBIOLOGY AND MOLECULAR BIOLOGY REVIEWS, Mar. 2011, p. 133–191 Vol. 75, No. 1 1092-2172/11/$12.00 doi:10.1128/MMBR.00015-10 Copyright © 2011, American Society for Microbiology. All Rights Reserved. Oxidative Stress Resistance in Deinococcus radiodurans† 1 1,2 Dea Slade * and Miroslav Radman http://mmbr.asm.org/ Universite´de Paris-Descartes, Faculte´deMe´decine, INSERM U1001, 156 Rue de Vaugirard, 75015 Paris, France,1 and Mediterranean Institute for Life Sciences, Mestrovicevo Setaliste bb, 21000 Split, Croatia2 INTRODUCTION .......................................................................................................................................................134 GENERAL PROPERTIES OF DEINOCOCCUS RADIODURANS.......................................................................134 Common Features of a “Strange” Bacterium.....................................................................................................134 Ecology of D. radiodurans.......................................................................................................................................135 D. radiodurans Physical Structure and Cell Division ........................................................................................135 Metabolic Configuration of D. radiodurans .........................................................................................................136 on March 25, 2015 by UNIVERSIDADE EST.PAULISTA JÚLIO DE Phylogeny of D. radiodurans ..................................................................................................................................140 Genetics of D. radiodurans.....................................................................................................................................140 Mobile Genetic Elements in D. radiodurans........................................................................................................141 DNA DAMAGE RESISTANCE AND DNA REPAIR MECHANISMS OF D. RADIODURANS.......................141 Ionizing Radiation Resistance of D. radiodurans ...............................................................................................144 Factors influencing radiation resistance .........................................................................................................144 Evolution of radiation resistance in D. radiodurans ......................................................................................145 Kinetics of DNA Repair in Gamma-Irradiated D. radiodurans........................................................................146 DNA Degradation in Irradiated D. radiodurans .................................................................................................146 Recombinational Processes in D. radiodurans DNA Repair .............................................................................148 Physical scaffolds for DNA repair in D. radiodurans.....................................................................................150 (i) Genome condensation in D. radiodurans................................................................................................150 MESQUITA FILHO (ii) Ring-like nucleoids in D. radiodurans ...................................................................................................150 (iii) DNA-membrane association in D. radiodurans...................................................................................151 (iv) Chromosome alignment in D. radiodurans...........................................................................................151 Enzymatic tools of recombinational repair in D. radiodurans......................................................................151 (i) The RecFOR pathway...............................................................................................................................151 (ii) RecA ...........................................................................................................................................................152 (iii) RadA, RuvABC, and RecG ....................................................................................................................154 (iv) The SSB proteins.....................................................................................................................................155 (v) RecD ...........................................................................................................................................................155 (vi) SbcCD .......................................................................................................................................................155 (vii) Novel deinococcal DNA repair proteins..............................................................................................156 Replication Processes in D. radiodurans DNA Repair.......................................................................................156 DNA Repair Checkpoints and Cell Division Control in D. radiodurans.........................................................158 The RecA-Independent Pathway of DSB Repair in D. radiodurans.................................................................159 Fidelity of DNA Repair in Irradiated D. radiodurans........................................................................................160 Desiccation Resistance of D. radiodurans ............................................................................................................160 Resistance of D. radiodurans to UV-C Radiation ...............................................................................................162 Kinetics and enzymology of the repair of UV-induced DNA damage in D. radiodurans ..........................162 Sensitivity of D. radiodurans to UV-A Radiation and Singlet Oxygen.............................................................163 Resistance of D. radiodurans to Mitomycin C.....................................................................................................163 Resistance of D. radiodurans to Base-Damaging Chemicals.............................................................................164 Base excision repair in D. radiodurans ............................................................................................................164 Chemical mutagenesis in D. radiodurans.........................................................................................................164 Mismatch Repair in D. radiodurans .....................................................................................................................165 Nonhomologous End Joining in D. radiodurans .................................................................................................165 STRESS RESPONSE IN D. RADIODURANS.........................................................................................................165 Stress Response Transcriptional Regulators......................................................................................................165 Induction of Gene Expression and Protein Synthesis in Response to Ionizing Radiation ..........................168 Protein Regulation in Response to Radiation Damage.....................................................................................168 PREVENTION AND TOLERANCE OF DNA AND PROTEIN DAMAGE IN D. RADIODURANS................169 Cell-Cleaning Proteins in D. radiodurans ............................................................................................................169 * Corresponding author. Mailing address: Universite´de Paris-Des- cartes, Faculte´deMe´decine, INSERM U1001, 156 Rue de Vaugirard, 75015 Paris, France. Phone: 0033140615494. Fax: 0033140615322. E-mail: [email protected]. † Supplemental material for this article may be found at http://mmbr .asm.org/. 133 Downloaded from 134 SLADE AND RADMAN MICROBIOL.MOL.BIOL.REV. Antioxidation Protection in D. radiodurans.........................................................................................................170 Catalases, superoxide dismutases, and peroxidases ......................................................................................172 Dps proteins ........................................................................................................................................................172 Carotenoids..........................................................................................................................................................172 Manganese complexes ........................................................................................................................................173 WHAT DETERMINES THE EXTREME RADIATION RESISTANCE OF D. RADIODURANS? ..................174 http://mmbr.asm.org/ SOME RAMIFICATIONS OF D. RADIODURANS OXIDATIVE STRESS RESISTANCE .............................175 Can D. radiodurans Provide a Means for Circumventing Aging and Cancer? ..............................................175 Oxidative stress, aging, and cancer..................................................................................................................176 DNA damage, aging, and cancer ......................................................................................................................176 Protein damage, aging, and cancer ..................................................................................................................176 Harnessing of D. radiodurans
Load more

Recommended publications
  • Deinococcus Radiodurans : La Recombinaison Entre S´Equencesr´Ep´Et´Eeset La Transformation Naturelle Solenne Ithurbide
    Variabilit´eg´en´etiquechez la bact´erieradior´esistante Deinococcus radiodurans : la recombinaison entre s´equencesr´ep´et´eeset la transformation naturelle Solenne Ithurbide To cite this version: Solenne Ithurbide. Variabilit´eg´en´etiquechez la bact´erieradior´esistante Deinococcus radio- durans : la recombinaison entre s´equencesr´ep´et´eeset la transformation naturelle. Biologie mol´eculaire.Universit´eParis Sud - Paris XI, 2015. Fran¸cais. <NNT : 2015PA112193>. <tel- 01374867> HAL Id: tel-01374867 https://tel.archives-ouvertes.fr/tel-01374867 Submitted on 2 Oct 2016 HAL is a multi-disciplinary open access L'archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destin´eeau d´ep^otet `ala diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publi´esou non, lished or not. The documents may come from ´emanant des ´etablissements d'enseignement et de teaching and research institutions in France or recherche fran¸caisou ´etrangers,des laboratoires abroad, or from public or private research centers. publics ou priv´es. UNIVERSITÉ PARIS-SUD ÉCOLE DOCTORALE 426 GÈNES GÉNOMES CELLULES Institut de Biologie Intégrative de la Cellule THÈSE DE DOCTORAT SCIENCES DE LA VIE ET DE LA SANTÉ par Solenne ITHURBIDE Variabilité génétique chez la bactérie radiorésistante Deinococcus radiodurans : La recombinaison entre séquences répétées et la transformation naturelle Soutenue le 23 Septembre 2015 Composition du jury : Directeur de thèse : Suzanne SOMMER Professeur
    [Show full text]
  • Horizontal Gene Transfer Elements: Plasmids in Antarctic Microorganisms
    Chapter 5 Horizontal Gene Transfer Elements: Plasmids in Antarctic Microorganisms Matías Giménez, Gastón Azziz, Paul R. Gill, and Silvia Batista Abstract Plasmids play an important role in the evolution of microbial communi- ties. These mobile genetic elements can improve host survival and may also be involved in horizontal gene transfer (HGT) events between individuals. Diverse culture-dependent and culture-independent approaches have been used to character- ize these mobile elements. Culture-dependent methods are usually associated with classical microbiological techniques. In the second approach, development of spe- cific protocols for analysis of metagenomes involves many challenges, including assembly of sequences and availability of a reliable database, which are crucial. In addition, alternative strategies have been developed for the characterization of plas- mid DNA in a sample, generically referred to as plasmidome. The Antarctic continent has environments with diverse characteristics, including some with very low temperatures, humidity levels, and nutrients. The presence of microorganisms and genetic elements capable of being transferred horizontally has been confirmed in these environments, and it is generally accepted that some of these elements, such as plasmids, actively participate in adaptation mechanisms of host microorganisms. Information related to structure and function of HGT elements in Antarctic bac- teria is very limited compared to what is known about HGT in bacteria from temper- ate/tropical environments. Some studies are done with biotechnological objectives. The search for mobile elements, such as plasmids, may be related to improve the expression of heterologous genes in host organisms growing at very low tempera- tures. More recently, however, additional studies have been done to detect plasmids in isolates, associated or not with specific phenotypes such as drug resistance.
    [Show full text]
  • Proquest Dissertations
    Division of Mycobacterial Research National Institute for Medical Research, Mill Hill London RecA expression and DNA damage in mycobacteria Nicola A Thomas June 1998 A thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in the Faculty of Science, University College of London. ProQuest Number: U642358 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest. ProQuest U642358 Published by ProQuest LLC(2015). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code. Microform Edition © ProQuest LLC. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 A bstr a ct Bacterial responses to DNA damage are highly conserved. One system, the SOS response, involves the co-ordinately induced expression of over 20 unlinked genes. The RecA protein plays a central role in the regulation of this response via its interaction with a repressor protein, LexA. The recA gene of Mycobacterium tuberculosis has previously been cloned and sequenced (Davis et al, 1991) and a LexA homologue has recently been identified (Movahedzadeh, 1996). The intracellular lifestyle of pathogenic mycobacteria constantly exposes them to hostile agents such as hydrogen peroxide. Consequently, the response of mycobacteria to DNA damage is of great interest.
    [Show full text]
  • Deinococcus Antarcticus Sp. Nov., Isolated from Soil
    International Journal of Systematic and Evolutionary Microbiology (2015), 65, 331–335 DOI 10.1099/ijs.0.066324-0 Deinococcus antarcticus sp. nov., isolated from soil Ning Dong,1,2 Hui-Rong Li,1 Meng Yuan,1,2 Xiao-Hua Zhang2 and Yong Yu1 Correspondence 1SOA Key Laboratory for Polar Science, Polar Research Institute of China, Shanghai 200136, Yong Yu PR China [email protected] 2College of Marine Life Sciences, Ocean University of China, Qingdao 266003, PR China A pink-pigmented, non-motile, coccoid bacterial strain, designated G3-6-20T, was isolated from a soil sample collected in the Grove Mountains, East Antarctica. This strain was resistant to UV irradiation (810 J m”2) and slightly more sensitive to desiccation as compared with Deinococcus radiodurans. Phylogenetic analyses based on the 16S rRNA gene sequence of the isolate indicated that the organism belongs to the genus Deinococcus. Highest sequence similarities were with Deinococcus ficus CC-FR2-10T (93.5 %), Deinococcus xinjiangensis X-82T (92.8 %), Deinococcus indicus Wt/1aT (92.5 %), Deinococcus daejeonensis MJ27T (92.3 %), Deinococcus wulumuqiensis R-12T (92.3 %), Deinococcus aquaticus PB314T (92.2 %) and T Deinococcus radiodurans DSM 20539 (92.2 %). Major fatty acids were C18 : 1v7c, summed feature 3 (C16 : 1v7c and/or C16 : 1v6c), anteiso-C15 : 0 and C16 : 0. The G+C content of the genomic DNA of strain G3-6-20T was 63.1 mol%. Menaquinone 8 (MK-8) was the predominant respiratory quinone. Based on its phylogenetic position, and chemotaxonomic and phenotypic characteristics, strain G3-6-20T represents a novel species of the genus Deinococcus, for which the name Deinococcus antarcticus sp.
    [Show full text]
  • Access to Electronic Thesis
    Access to Electronic Thesis Author: Khalid Salim Al-Abri Thesis title: USE OF MOLECULAR APPROACHES TO STUDY THE OCCURRENCE OF EXTREMOPHILES AND EXTREMODURES IN NON-EXTREME ENVIRONMENTS Qualification: PhD This electronic thesis is protected by the Copyright, Designs and Patents Act 1988. No reproduction is permitted without consent of the author. It is also protected by the Creative Commons Licence allowing Attributions-Non-commercial-No derivatives. If this electronic thesis has been edited by the author it will be indicated as such on the title page and in the text. USE OF MOLECULAR APPROACHES TO STUDY THE OCCURRENCE OF EXTREMOPHILES AND EXTREMODURES IN NON-EXTREME ENVIRONMENTS By Khalid Salim Al-Abri Msc., University of Sultan Qaboos, Muscat, Oman Mphil, University of Sheffield, England Thesis submitted in partial fulfillment for the requirements of the Degree of Doctor of Philosophy in the Department of Molecular Biology and Biotechnology, University of Sheffield, England 2011 Introductory Pages I DEDICATION To the memory of my father, loving mother, wife “Muneera” and son “Anas”, brothers and sisters. Introductory Pages II ACKNOWLEDGEMENTS Above all, I thank Allah for helping me in completing this project. I wish to express my thanks to my supervisor Professor Milton Wainwright, for his guidance, supervision, support, understanding and help in this project. In addition, he also stood beside me in all difficulties that faced me during study. My thanks are due to Dr. D. J. Gilmour for his co-supervision, technical assistance, his time and understanding that made some of my laboratory work easier. In the Ministry of Regional Municipalities and Water Resources, I am particularly grateful to Engineer Said Al Alawi, Director General of Health Control, for allowing me to carry out my PhD study at the University of Sheffield.
    [Show full text]
  • Non-Canonical Functions of the Bacterial Sos Response
    University of Pennsylvania ScholarlyCommons Publicly Accessible Penn Dissertations 2019 Non-Canonical Functions Of The aB cterial Sos Response Amanda Samuels University of Pennsylvania, [email protected] Follow this and additional works at: https://repository.upenn.edu/edissertations Part of the Microbiology Commons Recommended Citation Samuels, Amanda, "Non-Canonical Functions Of The aB cterial Sos Response" (2019). Publicly Accessible Penn Dissertations. 3253. https://repository.upenn.edu/edissertations/3253 This paper is posted at ScholarlyCommons. https://repository.upenn.edu/edissertations/3253 For more information, please contact [email protected]. Non-Canonical Functions Of The aB cterial Sos Response Abstract DNA damage is a pervasive environmental threat, as such, most bacteria encode a network of genes called the SOS response that is poised to combat genotoxic stress. In the absence of DNA damage, the SOS response is repressed by LexA, a repressor-protease. In the presence of DNA damage, LexA undergoes a self-cleavage reaction relieving repression of SOS-controlled effector genes that promote bacterial survival. However, depending on the bacterial species, the SOS response has an expanded role beyond DNA repair, regulating genes involved in mutagenesis, virulence, persistence, and inter-species competition. Despite a plethora of research describing the significant consequences of the SOS response, it remains unknown what physiologic environments induce and require the SOS response for bacterial survival. In Chapter 2, we utilize a commensal E. coli strain, MP1, and established that the SOS response is critical for sustained colonization of the murine gut. Significantly, in evaluating the origin of the genotoxic stress, we found that the SOS response was nonessential for successful colonization in the absence of the endogenous gut microbiome, suggesting that competing microbes might be the source of genotoxic stress.
    [Show full text]
  • Bacterial Diversity Assessment in Antarctic Terrestrial and Aquatic Microbial Mats: a Comparison Between Bidirectional Pyrosequencing and Cultivation
    Bacterial Diversity Assessment in Antarctic Terrestrial and Aquatic Microbial Mats: A Comparison between Bidirectional Pyrosequencing and Cultivation Bjorn Tytgat1*, Elie Verleyen2, Dagmar Obbels2, Karolien Peeters1¤a, Aaike De Wever2¤b, Sofie D’hondt2, Tim De Meyer3, Wim Van Criekinge3, Wim Vyverman2, Anne Willems1 1 Laboratory for Microbiology, Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium, 2 Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Ghent, Belgium, 3 Laboratory of Bioinformatics and Computational Genomics, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Ghent, Belgium Abstract The application of high-throughput sequencing of the 16S rRNA gene has increased the size of microbial diversity datasets by several orders of magnitude, providing improved access to the rare biosphere compared with cultivation-based approaches and more established cultivation-independent techniques. By contrast, cultivation-based approaches allow the retrieval of both common and uncommon bacteria that can grow in the conditions used and provide access to strains for biotechnological applications. We performed bidirectional pyrosequencing of the bacterial 16S rRNA gene diversity in two terrestrial and seven aquatic Antarctic microbial mat samples previously studied by heterotrophic cultivation. While, not unexpectedly, 77.5% of genera recovered by pyrosequencing were not among the isolates, 25.6% of the genera picked up by cultivation were not detected by pyrosequencing. To allow comparison between both techniques, we focused on the five phyla (Proteobacteria, Actinobacteria, Bacteroidetes, Firmicutes and Deinococcus-Thermus) recovered by heterotrophic cultivation. Four of these phyla were among the most abundantly recovered by pyrosequencing. Strikingly, there was relatively little overlap between cultivation and the forward and reverse pyrosequencing-based datasets at the genus (17.1– 22.2%) and OTU (3.5–3.6%) level (defined on a 97% similarity cut-off level).
    [Show full text]
  • Molecular Analysis of the Reca Gene and SOS Box of the Purple Non-Sulfur Bacterium Rhodopseudomonas Palustris No
    Microbiology (1999), 145, 1275-1 285 Printed in Great Britain Molecular analysis of the recA gene and SOS box of the purple non-sulfur bacterium Rhodopseudomonas palustris no. 7 Valerie Dumay,t Masayuki lnui and Hideaki Yukawa Author for correspondence: Hideaki Yukawa. Tel: +81 774 75 2308. Fax: + 81 774 75 2321. e-mail : yukawa(&rite.or.jp ~~~ ~~ Molecular Microbiology The red gene of the purple non-sulfur bacterium Rhodopseudomonas and Research palustris no. 7 was isolated by a PCR-based method and sequenced. The Institute of Innovative Technology for the Earth, complete nucleotide sequence consists of 1089 bp encoding a polypeptide of 9-2 Kizugawadai, Kizu-cho, 363 amino acids which is most closely related to the RecA proteins from Soraku-gun, Kyoto 619- species of Rhizobiaceae and Rhodospirillaceae. A recA-deficient strain of R. 0292, Japan palustris no. 7 was obtained by gene replacement. As expected, this strain exhibited increased sensitivity to DNA-damaging agents. Transcriptional fusions of the recA promoter region to lacZ confirmed that the R. palustris no. 7 recA gene is inducible by DNA damage. Primer extension analysis of recA mRNA located the recA gene transcriptional start. A sequential deletion of the fusion plasmid was used to delimit the promoter region of the recA gene. A gel mobility shift assay demonstrated that a DNA-protein complex is formed at this promoter region. This DNA-protein complex was not formed when protein extracts from cells treated with DNA-damaging agents were used, indicating that the binding protein is a repressor. Comparison of the minimal R. palustris no.
    [Show full text]
  • Jiao Da Biochemistry-2
    DNA Damage and Repair Guo-Min Li (李国民 ）, Ph.D. Professor James Gardner Chair in Cancer Research University of Kentucky College of Medicine DNA Damage and Repair Contents • DNA damage • DNA damage response • DNA repair – Direct reversal – Base excision repair – Nucleotide excision repair – Translesion synthesis – Mismatch repair – Double strand break repair • Recombination repair • Non-homologous end joining – Inter strand cross-link repair Major DNA Lesions DNA lesions and structures that elicit DNA response reactions. Some of the base backbone lesions and noncanonical DNA structures that elicit DNA response reactions are shown. O6MeGua indicates O6- methyldeoxyguanosine, T<>T indicates a cyclobutane thymine dimer, and the cross-link shown is cisplatin G-G interstrand cross-link. Endogenous DNA Damage Deamination of cytosine to uracil can spontaneously occurs to creates a U·G mismatch. Depurination removes a base from DNA, blocking replication and transcription. Mismatch Derived from Normal DNA Metabolism 5’ 3’ DNA replication errors DNA recombination DNA Damage and Repair Contents • DNA damage • DNA damage response • DNA repair – Direct reversal – Base excision repair – Nucleotide excision repair – Translesion synthesis – Mismatch repair – Double strand break repair • Recombination repair • Non-homologous end joining – Inter strand cross-link repair Cellular Response to DNA Damage A contemporary view of the general outline of the DNA damage response signal-transduction pathway. Arrowheads represent activating events and perpendicular ends represent inhibitory events. Cell- cycle arrest is depicted with a stop sign, apoptosis with a tombstone. The DNA helix with an arrow represents damage-induced transcription, while the DNA helix with several oval-shaped subunits represents damage-induced repair. For the purpose of simplicity, the network of interacting pathways are depicted as a linear pathway consisting of signals, sensors, transducers and effectors.
    [Show full text]
  • Polyphasic Systematics of Marine Bacteria and Their Alpha-Glucosidase Inhibitor Activity
    Polyphasic systematics of marine bacteria and their alpha-glucosidase inhibitor activity Thesis Submitted to AcSIR For the Award of the Degree of DOCTOR OF PHILOSOPHY In Biological Science By RAHUL BHOLESHANKAR MAWLANKAR AcSIR no. 10BB13J26036 Under the guidance of Research Supervisor Dr. Syed G. Dastager Research Co-supervisor Dr. Mahesh S. Dharne NCIM Resource Centre, Biochemical Science divison, CSIR-National Chemical Laboratory, Pune-411 008, India Table of contents Table of contents 1 Certificate 4 Declaration 5 Acknowledgment 6 List of fugures 9 List of tables 12 List of abbreviations 14 Abstract 16 Chapter 1. Introduction 19 1.1. Bacterial Systematics 20 1.1.1. Phenotypic analysis 22 1.1.2. Phylogenetic analysis 28 1.1.2.1. The 16S rRNA gene sequencing 29 1.1.2.2. Phylogenetic analysis 30 1.1.2.3. Whole genome analysis 32 1.1.3. Genotypic analysis 33 1.1.3.1. DNA-DNA hybridization (DDH) 33 1.1.3.2. Genomic DNA G+C content 35 1.1.3.3. Multi-locus sequence typing (MLST) 36 1.1.3.4. DNA profiling 37 1.2. Marine bacteria and their potentials 38 1.3. Marine sediments 39 1.4. Alpha-glucosidase inhibitor 44 1.4.1. Acarbose 45 1.4.2. Voglibose 48 1.4.3. Nojirimycin 49 1.4.4. 1-deoxynojirimycin 50 1.4.5. Miglitol 51 1.5. Alpha-glucosidase inhibitors from marine isolates 52 Chapter 2. Polyphasic Systematic approach 55 2.1. Overview 56 2.2. Isolation of marine sediment sample 57 2.3. Characterization 57 2.3.1.
    [Show full text]
  • Príloha Č. 1. Králová S. (2017) Role of Fatty Acids in Cold Adaptation Of
    Príloha č. 1. Králová S. (2017) Role of fatty acids in cold adaptation of Antarctic psychrophilic Flavobacterium spp. Syst. Appl. Microbiol., 40(6): 329-333. Doi: 10.1016/j.syapm.2017.06.001 Systematic and Applied Microbiology 40 (2017) 329–333 Contents lists available at ScienceDirect Systematic and Applied Microbiology j ournal homepage: www.elsevier.de/syapm Role of fatty acids in cold adaptation of Antarctic psychrophilic Flavobacterium spp. Stanislava Králová Czech Collection of Microorganisms, Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno, Czech Republic a r t i c l e i n f o a b s t r a c t Article history: Cold-loving microorganisms developed numerous adaptation mechanisms allowing them to survive in Received 9 May 2017 extremely cold habitats, such as adaptation of the cell membrane. The focus of this study was on the Received in revised form 8 June 2017 membrane fatty acids of Antarctic Flavobacterium spp., and their adaptation response to cold-stress. Fatty Accepted 12 June 2017 acids and cold-response of Antarctic flavobacteria was also compared to mesophilic and thermophilic members of the genus Flavobacterium. The results showed that the psychrophiles produced more types Keywords: of major fatty acids than meso- and thermophilic members of this genus, namely C15:1 iso G, C15:0 iso, Flavobacterium C15:0 anteiso, C15:1 ω6c, C15:0 iso 3OH, C17:1 ω6c, C16:0 iso 3OH and C17:0 iso 3OH, summed features 3 Antarctic bacteria ω ω ω Adaptation (C16:1 7cand/or C16:1 6c) and 9 (C16:0 10-methyl and/or C17:1 iso 9c).
    [Show full text]
  • Viewed Manually
    Cambray et al. Mobile DNA 2011, 2:6 http://www.mobilednajournal.com/content/2/1/6 RESEARCH Open Access Prevalence of SOS-mediated control of integron integrase expression as an adaptive trait of chromosomal and mobile integrons Guillaume Cambray1†, Neus Sanchez-Alberola2,3†, Susana Campoy2, Émilie Guerin4, Sandra Da Re4, Bruno González-Zorn5, Marie-Cécile Ploy4, Jordi Barbé3, Didier Mazel1* and Ivan Erill3* Abstract Background: Integrons are found in hundreds of environmental bacterial species, but are mainly known as the agents responsible for the capture and spread of antibiotic-resistance determinants between Gram-negative pathogens. The SOS response is a regulatory network under control of the repressor protein LexA targeted at addressing DNA damage, thus promoting genetic variation in times of stress. We recently reported a direct link between the SOS response and the expression of integron integrases in Vibrio cholerae and a plasmid-borne class 1 mobile integron. SOS regulation enhances cassette swapping and capture in stressful conditions, while freezing the integron in steady environments. We conducted a systematic study of available integron integrase promoter sequences to analyze the extent of this relationship across the Bacteria domain. Results: Our results showed that LexA controls the expression of a large fraction of integron integrases by binding to Escherichia coli-like LexA binding sites. In addition, the results provide experimental validation of LexA control of the integrase gene for another Vibrio chromosomal integron and for a multiresistance plasmid harboring two integrons. There was a significant correlation between lack of LexA control and predicted inactivation of integrase genes, even though experimental evidence also indicates that LexA regulation may be lost to enhance expression of integron cassettes.
    [Show full text]