# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 5214 | 0 | 0.9881 | Comparative genomic analysis of a new tellurite-resistant Psychrobacter strain isolated from the Antarctic Peninsula. The Psychrobacter genus is a cosmopolitan and diverse group of aerobic, cold-adapted, Gram-negative bacteria exhibiting biotechnological potential for low-temperature applications including bioremediation. Here, we present the draft genome sequence of a bacterium from the Psychrobacter genus isolated from a sediment sample from King George Island, Antarctica (3,490,622 bp; 18 scaffolds; G + C = 42.76%). Using phylogenetic analysis, biochemical properties and scanning electron microscopy the bacterium was identified as Psychrobacter glacincola BNF20, making it the first genome sequence reported for this species. P. glacincola BNF20 showed high tellurite (MIC 2.3 mM) and chromate (MIC 6.0 mM) resistance, respectively. Genome-wide nucleotide identity comparisons revealed that P. glacincola BNF20 is highly similar (>90%) to other uncharacterized Psychrobacter spp. such as JCM18903, JCM18902, and P11F6. Bayesian multi-locus phylogenetic analysis showed that P. glacincola BNF20 belongs to a polyphyletic clade with other bacteria isolated from polar regions. A high number of genes related to metal(loid) resistance were found, including tellurite resistance genetic determinants located in two contigs: Contig LIQB01000002.1 exhibited five ter genes, each showing putative promoter sequences (terACDEZ), whereas contig LIQB1000003.2 showed a variant of the terZ gene. Finally, investigating the presence and taxonomic distribution of ter genes in the NCBI's RefSeq bacterial database (5,398 genomes, as January 2017), revealed that 2,623 (48.59%) genomes showed at least one ter gene. At the family level, most (68.7%) genomes harbored one ter gene and 15.6% exhibited five (including P. glacincola BNF20). Overall, our results highlight the diverse nature (genetic and geographic diversity) of the Psychrobacter genus, provide insights into potential mechanisms of metal resistance, and exemplify the benefits of sampling remote locations for prospecting new molecular determinants. | 2018 | 29479501 |
| 6386 | 1 | 0.9876 | Distribution of antibiotic and metal resistance genes in two glaciers of North Sikkim, India. Glacier studies as of late have ruffled many eyeballs, exploring this frigid ecology to understand the impact of climate change. Mapquesting the glaciers led to the discovery of concealed world of "psychrophiles" harboring in it. In the present study, the antibiotic resistance genes (ARGs) and heavy metal resistance genes (MRGs) were evaluated through both the culture-dependent and culture-independent methods. Samples were collected from two different glaciers, i.e., debris-covered glacier (Changme Khangpu) and debris-free glacier (Changme Khang). Functional metagenomics of both the glacier samples, provided evidence of presence of resistant genes against various antibiotic groups. Bacitracin resistant gene (bacA) was the predominant ARG in both the glaciers. MRGs in both the glacier samples were diversified as the genes detected were resistant against various heavy metals such as arsenic, tungsten, mercury, zinc, chromium, copper, cobalt, and iron. Unique MRGs identified from Changme Khangpu glacier were resistant to copper (cutA, cutE, cutC, cutF, cueR, copC, and copB) and chromium (yelf, ruvB, nfsA, chrR, and chrA) whereas, from Changme Khang glacier they showed resistance against cobalt (mgtA, dmef, corD, corC, corB, and cnrA), and iron (yefD, yefC, yefB, and yefA) heavy metals. ARGs aligned maximum identity with Gram-negative psychrotolerant bacteria. The cultured bacterial isolates showed tolerance to high concentrations of tested heavy metal solutions. Interestingly, some of the antibiotic resistant bacterial isolates also showed tolerance towards the higher concentrations of heavy metals. Thus, an introspection of the hypothesis of co-occurrence and/co-selection of ARGs and MRGs in such environments has been highlighted here. | 2020 | 32888596 |
| 8643 | 2 | 0.9873 | Diversity of Phototrophic Genes Suggests Multiple Bacteria May Be Able to Exploit Sunlight in Exposed Soils from the Sør Rondane Mountains, East Antarctica. Microbial life in exposed terrestrial surface layers in continental Antarctica is faced with extreme environmental conditions, including scarcity of organic matter. Bacteria in these exposed settings can therefore be expected to use alternative energy sources such as solar energy, abundant during the austral summer. Using Illumina MiSeq sequencing, we assessed the diversity and abundance of four conserved protein encoding genes involved in different key steps of light-harvesting pathways dependent on (bacterio)chlorophyll (pufM, bchL/chlL, and bchX genes) and rhodopsins (actinorhodopsin genes), in exposed soils from the Sør Rondane Mountains, East Antarctica. Analysis of pufM genes, encoding a subunit of the type 2 photochemical reaction center found in anoxygenic phototrophic bacteria, revealed a broad diversity, dominated by Roseobacter- and Loktanella-like sequences. The bchL and chlL, involved in (bacterio)chlorophyll synthesis, on the other hand, showed a high relative abundance of either cyanobacterial or green algal trebouxiophyceael chlL reads, depending on the sample, while most bchX sequences belonged mostly to previously unidentified phylotypes. Rhodopsin-containing phototrophic bacteria could not be detected in the samples. Our results, while suggesting that Cyanobacteria and green algae are the main phototrophic groups, show that light-harvesting bacteria are nevertheless very diverse in microbial communities in Antarctic soils. | 2016 | 28066352 |
| 479 | 3 | 0.9870 | Genome sequences of Methylobacterium and Methylorubrum isolates from Cd-contaminated soils in the Tar Creek Superfund site. Soil bacteria were isolated from the Tar Creek Superfund site in the presence of cadmium. Eight of these strains belong to the genus Methylobacterium, whereas one strain belongs to the genus Methylorubrum. Here, we report drafts of their genome sequences and highlight cadmium-resistance genes required in an exceptionally contaminated environment. | 2025 | 39835800 |
| 5141 | 4 | 0.9866 | Flavobacterium flabelliforme sp. nov. and Flavobacterium geliluteum sp. nov., Two Multidrug-Resistant Psychrotrophic Species Isolated From Antarctica. Despite unfavorable Antarctic conditions, such as cold temperatures, freeze-thaw cycles, high ultraviolet radiation, dryness and lack of nutrients, microorganisms were able to adapt and surprisingly thrive in this environment. In this study, eight cold-adapted Flavobacterium strains isolated from a remote Antarctic island, James Ross Island, were studied using a polyphasic taxonomic approach to determine their taxonomic position. Phylogenetic analyses based on the 16S rRNA gene and 92 core genes clearly showed that these strains formed two distinct phylogenetic clusters comprising three and five strains, with average nucleotide identities significantly below 90% between both proposed species as well as between their closest phylogenetic relatives. Phenotyping revealed a unique pattern of biochemical and physiological characteristics enabling differentiation from the closest phylogenetically related Flavobacterium spp. Chemotaxonomic analyses showed that type strains P4023(T) and P7388(T) were characterized by the major polyamine sym-homospermidine and a quinone system containing predominantly menaquinone MK-6. In the polar lipid profile phosphatidylethanolamine, an ornithine lipid and two unidentified lipids lacking a functional group were detected as major lipids. These characteristics along with fatty acid profiles confirmed that these species belong to the genus Flavobacterium. Thorough genomic analysis revealed the presence of numerous cold-inducible or cold-adaptation associated genes, such as cold-shock proteins, proteorhodopsin, carotenoid biosynthetic genes or oxidative-stress response genes. Genomes of type strains surprisingly harbored multiple prophages, with many of them predicted to be active. Genome-mining identified biosynthetic gene clusters in type strain genomes with a majority not matching any known clusters which supports further exploratory research possibilities involving these psychrotrophic bacteria. Antibiotic susceptibility testing revealed a pattern of multidrug-resistant phenotypes that were correlated with in silico antibiotic resistance prediction. Interestingly, while typical resistance finder tools failed to detect genes responsible for antibiotic resistance, genomic prediction confirmed a multidrug-resistant profile and suggested even broader resistance than tested. Results of this study confirmed and thoroughly characterized two novel psychrotrophic Flavobacterium species, for which the names Flavobacterium flabelliforme sp. nov. and Flavobacterium geliluteum sp. nov. are proposed. | 2021 | 34745033 |
| 5876 | 5 | 0.9864 | Profiling of biodegradation and bacterial 16S rRNA genes in diverse contaminated ecosystems using 60-mer oligonucleotide microarray. We have developed an oligonucleotide microarray for the detection of biodegradative genes and bacterial diversity and tested it in five contaminated ecosystems. The array has 60-mer oligonucleotide probes comprising 14,327 unique probes derived from 1,057 biodegradative genes and 880 probes representing 110 phylogenetic genes from diverse bacterial communities, and we named it as BiodegPhyloChip. The biodegradative genes are involved in the transformation of 133 chemical pollutants. Validation of the microarray for its sensitivity specificity and quantitation were performed using DNA isolated from well-characterized mixed bacterial cultures also having non-target strains, pure degrader strains, and environmental DNA. Application of the developed array using DNA extracted from five different contaminated sites led to the detection of 186 genes, including 26 genes unique to the individual sites. Hybridization of 16S rRNA probes revealed the presence of bacteria similar to well-characterized genera involved in biodegradation of various pollutants. Genes involved in complete degradation pathways for hexachlorocyclohexane (lin), 1,2,4-trichlorobenzene (tcb), naphthalene (nah), phenol (mph), biphenyl (bph), benzene (ben), toluene (tbm), xylene (xyl), phthalate (pht), Salicylate (sal), and resistance to mercury (mer) were detected with highest intensity. The most abundant genes belonged to the enzyme hydroxylases, monooxygenases, and dehydrogenases which were present in all the five samples. Thus, the array developed and validated here shall be useful in assessing not only the biodegradative potential but also the composition of environmentally useful bacteria, simultaneously, from hazardous ecosystems. | 2011 | 21503758 |
| 5187 | 6 | 0.9864 | Recovery of 52 bacterial genomes from the fecal microbiome of the domestic cat (Felis catus) using Hi-C proximity ligation and shotgun metagenomics. We used Hi-C proximity ligation with shotgun sequencing to retrieve metagenome-assembled genomes (MAGs) from the fecal microbiomes of two domestic cats (Felis catus). The genomes were assessed for completeness and contamination, classified taxonomically, and annotated for putative antimicrobial resistance (AMR) genes. | 2023 | 37695121 |
| 474 | 7 | 0.9864 | Novel antibiotic resistance profiles in bacteria isolated from oil fly larvae Helaeomyia petrolei living in the La Brea Tar Pits. Larvae from the petroleum oil fly, Helaeomyia petrolei, live in the asphaltene and polyaromatic hydrocarbon rich asphalt seeps of Rancho La Brea, Los Angeles, California. These larvae pass high amounts of viscous asphalt through their digestive system, and their gut microbiota is exposed to these extreme conditions. Environmental stress response mechanisms can co-select for antibiotic resistance, and in the current study we used 16S rRNA and genomic sequencing along with the Comprehensive Antibiotic Resistance Database (CARD) tools to characterize antibiotic resistance profiles from six bacteria previously isolated from the oil fly larval intestinal tract, linking phenotypic and genotypic resistance profiles. The isolates contain a core set of antibiotic resistance determinants along with determinants that are rarely found in these species. Comparing these oil fly isolates to the phenotypic prevalence data generated by the CARD Resistance Gene Identifier revealed sixteen instances where the oil fly bacteria appeared to carry a resistance not seen in related taxa in the database, suggesting a novel suite of resistance families in the oil fly isolates compared to other members of the same taxa. Results highlight the functional duality of genes that simultaneously code for antibiotic resistance and survival under extreme conditions, and expand our understanding of the ecological and evolutionary role of antibiotic resistance genes in environmental habitats. | 2024 | 39718641 |
| 817 | 8 | 0.9863 | Mercury resistance transposons in Bacilli strains from different geographical regions. A total of 65 spore-forming mercury-resistant bacteria were isolated from natural environments worldwide in order to understand the acquisition of additional genes by and dissemination of mercury resistance transposons across related Bacilli genera by horizontal gene movement. PCR amplification using a single primer complementary to the inverted repeat sequence of TnMERI1-like transposons showed that 12 of 65 isolates had a transposon-like structure. There were four types of amplified fragments: Tn5084, Tn5085, Tn(d)MER3 (a newly identified deleted transposon-like fragment) and Tn6294 (a newly identified transposon). Tn(d)MER3 is a 3.5-kb sequence that carries a merRETPA operon with no merB or transposase genes. It is related to the mer operon of Bacillus licheniformis strain FA6-12 from Russia. DNA homology analysis shows that Tn6294 is an 8.5-kb sequence that is possibly derived from Tn(d)MER3 by integration of a TnMERI1-type transposase and resolvase genes and in addition the merR2 and merB1 genes. Bacteria harboring Tn6294 exhibited broad-spectrum mercury resistance to organomercurial compounds, although Tn6294 had only merB1 and did not have the merB2 and merB3 sequences for organomercurial lyases found in Tn5084 of B. cereus strain RC607. Strains with Tn6294 encode mercuric reductase (MerA) of less than 600 amino acids in length with a single N-terminal mercury-binding domain, whereas MerA encoded by strains MB1 and RC607 has two tandem domains. Thus, Tn(d)MER3 and Tn6294 are shorter prototypes for TnMERI1-like transposons. Identification of Tn6294 in Bacillus sp. from Taiwan and in Paenibacillus sp. from Antarctica indicates the wide horizontal dissemination of TnMERI1-like transposons across bacterial species and geographical barriers. | 2016 | 26802071 |
| 5135 | 9 | 0.9862 | Arsenotrophic Achromobacter aegrifaciens strains isolated from arsenic contaminated tubewell water and soil sources shared similar genomic potentials. BACKGROUND: Arsenic (As), found in diverse ecosystems, poses major public health risks in various parts of the world. Arsenotrophic bacteria in contaminated environments help reduce toxicity by converting arsenite (AsIII) to less harmful arsenate (AsV). We assumed that Achromobacter aegrifaciens strains from As-contaminated tubewell water and soil would share similar genomic characteristics associated with arsenic detoxification and bioremediation. To investigate this, we employed both culture-dependent and culture-independent viz. whole genome sequencing (WGS) methods to thoroughly elucidate the phenotypic and genotypic features of two A. aegrifaciens strains isolated from As-contaminated tubewell water (BAW48) and soil (BAS32) samples collected in the Bogura district of Bangladesh. RESULTS: Both BAW48 and BAS32 isolates demonstrated As(III) oxidation in the KMNO4 test, which was corroborated by molecular analysis confirming the presence of aioA and arsB genes in both strains. These strains were found to be phylogenetically related to many strains of Achromobacter spp., isolated from biological inorganic reactors, environmental soils, sediments and human clinical samples across diverse geographical regions. Moreover, both strains possessed distinct heavy metal resistance genes conferring resistance to Co, Zn, Cu, Cd, Hg, As, and Cr. Three As gene clusters such as As(III) oxidizing aioBA, As(III) reducing arsRCDAB and the MMA(III) oxidizing ars resistance gene (arsHCsO) cluster were predicted in both genomes of A. aegrifaciens. Further genomic analyses revealed similar profiles in both strains, with mobile genetic elements, antimicrobials and heavy metal resistance genes, virulence genes, and metabolic features. Pangenome and synteny analysis showed that the two genomes are evolutionary distinct from other strains, but closely related to one another. CONCLUSION: The genomic data confirmed that A. aegrifaciens strains can oxidize As(III) and detoxify heavy metals like As, suggesting their potential for As detoxification and bioremediation. These findings align with our assumption and provide a basis for developing sustainable solutions for bioremediation efforts in As-contaminated environments. | 2024 | 39627700 |
| 6117 | 10 | 0.9860 | Isolation and characterization of the heavy metal resistant bacteria CCNWRS33-2 isolated from root nodule of Lespedeza cuneata in gold mine tailings in China. A total of 108 strains of bacteria were isolated from root nodules of wild legumes growing in gold mine tailings in northwest of China and were tested for heavy metal resistance. The results showed that the bacterial strain CCNWRS33-2 isolated from Lespedeza cuneata was highly resistant to copper, cadmium, lead and zinc. The strain had a relatively high mean specific growth rate under each heavy metal stress test and exhibited a high degree of bioaccumulation ability. The partial sequence of the copper resistance gene copA was amplified from the strain and a sequence comparison with our Cu-resistant PCR fragment showed a high homology with Cu-resistant genes from other bacteria. Phylogenetic analysis based on the 16S rRNA gene sequence showed that CCNWRS33-2 belongs to the Rhizobium-Agrobacterium branch and it had 98.9% similarity to Agrobactrium tumefaciens LMG196. | 2009 | 18562095 |
| 468 | 11 | 0.9860 | Selected chitinase genes in cultured and uncultured marine bacteria in the alpha- and gamma-subclasses of the proteobacteria. PCR primers were patterned after chitinase genes in four gamma-proteobacteria in the families Alteromonadaceae and Enterobacteriaceae (group I chitinases) and used to explore the occurrence and diversity of these chitinase genes in cultured and uncultured marine bacteria. The PCR results from 104 bacterial strains indicated that this type of chitinase gene occurs in two major groups of marine bacteria, alpha- and gamma-proteobacteria, but not the Cytophaga-Flavobacter group. Group I chitinase genes also occur in some viruses infecting arthropods. Phylogenetic analysis indicated that similar group I chitinase genes occur in taxonomically related bacteria. However, the overall phylogeny of chitinase genes did not correspond to the phylogeny of 16S rRNA genes, possibly due to lateral transfer of chitinase genes between groups of bacteria, but other mechanisms, such as gene duplication, cannot be ruled out. Clone libraries of chitinase gene fragments amplified from coastal Pacific Ocean and estuarine Delaware Bay bacterioplankton revealed similarities and differences between cultured and uncultured bacteria. We had hypothesized that cultured and uncultured chitin-degrading bacteria would be very different, but in fact, clones having nucleotide sequences identical to those of chitinase genes of cultured alpha-proteobacteria dominated both libraries. The other clones were similar but not identical to genes in cultured gamma-proteobacteria, including vibrios and alteromonads. Our results suggest that a closer examination of chitin degradation by alpha-proteobacteria will lead to a better understanding of chitin degradation in the ocean. | 2000 | 10698791 |
| 2605 | 12 | 0.9860 | Satellite tracking of gulls and genomic characterization of faecal bacteria reveals environmentally mediated acquisition and dispersal of antimicrobial-resistant Escherichia coli on the Kenai Peninsula, Alaska. Gulls (Larus spp.) have frequently been reported to carry Escherichia coli exhibiting antimicrobial resistance (AMR E. coli); however, the pathways governing the acquisition and dispersal of such bacteria are not well described. We equipped 17 landfill-foraging gulls with satellite transmitters and collected gull faecal samples longitudinally from four locations on the Kenai Peninsula, Alaska to assess: (a) gull attendance and transitions between sites, (b) spatiotemporal prevalence of faecally shed AMR E. coli, and (c) genomic relatedness of AMR E. coli isolates among sites. We also sampled Pacific salmon (Oncorhynchus spp.) harvested as part of personal-use dipnet fisheries at two sites to assess potential contamination with AMR E. coli. Among our study sites, marked gulls most commonly occupied the lower Kenai River (61% of site locations) followed by the Soldotna landfill (11%), lower Kasilof River (5%) and upper Kenai River (<1%). Gulls primarily moved between the Soldotna landfill and the lower Kenai River (94% of transitions among sites), which were also the two locations with the highest prevalence of AMR E. coli. There was relatively high spatial and temporal variability in AMR E. coli prevalence in gull faeces and there was no evidence of contamination on salmon harvested in personal-use fisheries. We identified E. coli sequence types and AMR genes of clinical importance, with some isolates possessing genes associated with resistance to as many as eight antibiotic classes. Our findings suggest that gulls acquire AMR E. coli at habitats with anthropogenic inputs and subsequent movements may represent pathways through which AMR is dispersed. | 2019 | 30980689 |
| 6132 | 13 | 0.9860 | Molecular characterization of copper resistance genes from Xanthomonas citri subsp. citri and Xanthomonas alfalfae subsp. citrumelonis. Copper sprays have been widely used for control of endemic citrus canker caused by Xanthomonas citri subsp. citri in citrus-growing areas for more than 2 decades. Xanthomonas alfalfae subsp. citrumelonis populations were also exposed to frequent sprays of copper for several years as a protective measure against citrus bacterial spot (CBS) in Florida citrus nurseries. Long-term use of these bactericides has led to the development of copper-resistant (Cu(r)) strains in both X. citri subsp. citri and X. alfalfae subsp. citrumelonis, resulting in a reduction of disease control. The objectives of this study were to characterize for the first time the genetics of copper resistance in X. citri subsp. citri and X. alfalfae subsp. citrumelonis and to compare these organisms to other Cu(r) bacteria. Copper resistance determinants from X. citri subsp. citri strain A44(pXccCu2) from Argentina and X. alfalfae subsp. citrumelonis strain 1381(pXacCu2) from Florida were cloned and sequenced. Open reading frames (ORFs) related to the genes copL, copA, copB, copM, copG, copC, copD, and copF were identified in X. citri subsp. citri A44. The same ORFs, except copC and copD, were also present in X. alfalfae subsp. citrumelonis 1381. Transposon mutagenesis of the cloned copper resistance determinants in pXccCu2 revealed that copper resistance in X. citri subsp. citri strain A44 is mostly due to copL, copA, and copB, which are the genes in the cloned cluster with the highest nucleotide homology (≥ 92%) among different Cu(r) bacteria. | 2011 | 21515725 |
| 3669 | 14 | 0.9859 | Detection of clinically relevant antimicrobial resistance determinants in warm-blooded marine animals in Livingston Island (South Shetland Islands, Antarctica): A field-based molecular genetics study. Molecular genetic studies of stools were performed to assess the spread of some clinically relevant antimicrobial resistance determinants (ARD) in a gentoo penguin (Pygoscelis papua) and an Antarctic fur seal (Arctocephalus gazella) on Livingston Island. Glycopeptide resistance genes (vanA/vanD and vanB) were detected in both fecal samples, while the penguin's one was also mecA-positive and bla(NDM)-positive. Because of the remoteness and the isolation of the sampling locations, the carriage of vancomycin-resistant Enterococcus spp., methicillin-resistant Staphylococcus aureus, and NDM-producing Enterobacterales or other gram-negative bacilli suggested an ocean pollution with antibiotic resistant bacteria (ARB). Additionally, due to the type of ARD we detected, our results are alarming, and they cannot be explained only with agricultural and/or aquacultural pollution. Even though the current study is a preliminary one, it also demonstrates the potential of the field genetics analyses carried out with minimal equipment as a reliable monitoring tool for pollution with ARB. | 2022 | 35597002 |
| 467 | 15 | 0.9859 | Aerobic anoxygenic photosynthesis genes and operons in uncultured bacteria in the Delaware River. Photosynthesis genes and operons of aerobic anoxygenic photosynthetic (AAP) bacteria have been examined in a variety of marine habitats, but genomic information about freshwater AAP bacteria is lacking. The goal of this study was to examine photosynthesis genes of AAP bacteria in the Delaware River. In a fosmid library, we found two clones bearing photosynthesis gene clusters with unique gene content and organization. Both clones contained 37 open reading frames, with most of those genes encoding known AAP bacterial proteins. The genes in one fosmid were most closely related to those of AAP bacteria in the Rhodobacter genus. The genes of the other clone were related to those of freshwater beta-proteobacteria. Both clones contained the acsF gene, which is required for aerobic bacteriochlorophyll synthesis, suggesting that these bacteria are not anaerobes. The beta-proteobacterial fosmid has the puf operon B-A-L-M-C and is the first example of an uncultured bacterium with this operon structure. The alpha-3-proteobacterial fosmid has a rare gene order (Q-B-A-L-M-X), previously observed only in the Rhodobacter genus. Phylogenetic analyses of photosynthesis genes revealed a possible freshwater cluster of AAP beta-proteobacteria. The data from both Delaware River clones suggest there are groups of freshwater or estuarine AAP bacteria distinct from those found in marine environments. | 2005 | 16309388 |
| 8441 | 16 | 0.9859 | Genomic and phenotypic attributes of novel salinivibrios from stromatolites, sediment and water from a high altitude lake. BACKGROUND: Salinivibrios are moderately halophilic bacteria found in salted meats, brines and hypersaline environments. We obtained three novel conspecific Salinivibrio strains closely related to S. costicola, from Socompa Lake, a high altitude hypersaline Andean lake (approx. 3,570 meters above the sea level). RESULTS: The three novel Salinivibrio spp. were extremely resistant to arsenic (up to 200 mM HAsO42-), NaCl (up to 15%), and UV-B radiation (19 KJ/m2, corresponding to 240 minutes of exposure) by means of phenotypic tests. Our subsequent draft genome ionsequencing and RAST-based genome annotation revealed the presence of genes related to arsenic, NaCl, and UV radiation resistance. The three novel Salinivibrio genomes also had the xanthorhodopsin gene cluster phylogenetically related to Marinobacter and Spiribacter. The genomic taxonomy analysis, including multilocus sequence analysis, average amino acid identity, and genome-to-genome distance revealed that the three novel strains belong to a new Salinivibrio species. CONCLUSIONS: Arsenic resistance genes, genes involved in DNA repair, resistance to extreme environmental conditions and the possible light-based energy production, may represent important attributes of the novel salinivibrios, allowing these microbes to thrive in the Socompa Lake. | 2014 | 24927949 |
| 6126 | 17 | 0.9859 | The draft genome of Andean Rhodopseudomonas sp. strain AZUL predicts genome plasticity and adaptation to chemical homeostasis. The genus Rhodopseudomonas comprises purple non-sulfur bacteria with extremely versatile metabolisms. Characterization of several strains revealed that each is a distinct ecotype highly adapted to its specific micro-habitat. Here we present the sequencing, genomic comparison and functional annotation of AZUL, a Rhodopseudomonas strain isolated from a high altitude Andean lagoon dominated by extreme conditions and fluctuating levels of chemicals. Average nucleotide identity (ANI) analysis of 39 strains of this genus showed that the genome of AZUL is 96.2% identical to that of strain AAP120, which suggests that they belong to the same species. ANI values also show clear separation at the species level with the rest of the strains, being more closely related to R. palustris. Pangenomic analyses revealed that the genus Rhodopseudomonas has an open pangenome and that its core genome represents roughly 5 to 12% of the total gene repertoire of the genus. Functional annotation showed that AZUL has genes that participate in conferring genome plasticity and that, in addition to sharing the basal metabolic complexity of the genus, it is also specialized in metal and multidrug resistance and in responding to nutrient limitation. Our results also indicate that AZUL might have evolved to use some of the mechanisms involved in resistance as redox reactions for bioenergetic purposes. Most of those features are shared with strain AAP120, and mainly involve the presence of additional orthologs responsible for the mentioned processes. Altogether, our results suggest that AZUL, one of the few bacteria from its habitat with a sequenced genome, is highly adapted to the extreme and changing conditions that constitute its niche. | 2022 | 36494611 |
| 6101 | 18 | 0.9859 | Heavy-metal resistance mechanisms developed by bacteria from Lerma-Chapala basin. Heavy-metal (HM) contamination is a huge environmental problem in many countries including Mexico. Currently, microorganisms with multiple heavy-metal resistance and/or plant-promoting characteristics have been widely used for bioremediation of HM-contaminated soils. The aim of the study was isolated bacteria with multiple heavy-metal resistance and to determinate the resistance mechanism developed by these organisms. A total of 138 aerobic bacteria were isolated from soil and sediments surrounding the Lerma-Chapala basin located in the boundary of the States of Michoacán and Jalisco states of Mexico. One hundred and eight strains showed at least 1 plant growth-promoting features. The Lerma-Chapala basin bacteria were also resistant to high concentrations of HMs including the metalloid arsenic. Sequence analysis of 16S RNA genes reveled that these bacteria were mainly affiliated to the phyla Proteobacteria (38%), Firmicutes (31%) and Actinobacteria (25%), covering 21 genera with Bacillus as the most abundant one. Among them, at least 27 putative novel species were detected in the genera Acinetobacter, Arthrobacter, Bacillus, Agrobacterium, Dyadobacter, Enterobacter, Exiguobacterium, Kluyvera, Micrococcus, Microbacterium and Psychrobacter. In addition, these bacteria developed various heavy-metal-resistance mechanisms, such as biosorption/bioaccumulation, immobilization and detoxification. Therefore, the bacteria isolated from soils and sediments of Lerma-Chapala basin could be used in bioremediation strategies. | 2021 | 33491161 |
| 4457 | 19 | 0.9858 | Using genomics to explore the epidemiology of vancomycin resistance in a sewage system. VanHAX-mediated glycopeptide resistance has been consistently high in one of the three main sewer systems in Copenhagen, Lynetten, for +20 years. To explore this for other glycopeptide resistance genes, and whether the colonization has resulted in establishment of multiple bacterial taxa, we mapped 505 shotgun metagenomic data sets from the inlet of three sewage treatment plants to 831 different glycopeptide resistance genes. Only vanHAX and vanHBX genes were differentially abundant in Lynetten. Analyses of eight contigs suggested limited variations in the flanking regions. Proximity ligation metagenomic analysis of 12 samples from Lynetten identified 441 and 5 paired reads mapping to vanHAX and vanHBX, respectively. The other end of these reads was mapped to generated metagenomic-assembled genomes and NCBI using BLAST. vanHBX could only be linked to the phylum level (Bacillota). Plasmid analysis of vanHBX Hi-C contigs showed that these were mainly located on plasmids reported found in enterococci species. Most vanHAX-linked reads could only be linked to phylum and class level, but some reads were assigned to Enterococcus faecium (7 reads), Enterococcus faecalis (4 reads), Paenibacillus apiarius (2 reads), and Paenibacillus thiaminolyticus (27 reads). Ten of the 20 Hi-C contigs-containing vanHAX were annotated as plasmid, all reported found in Enterococcus species. This study shows that while Hi-C technology is valuable for linking antimicrobial resistance genes to bacterial taxa, it suffers from challenges in reliably mapping the linked read to a genomic region with sufficient taxonomic information. Our results also suggest that over the +20 years of colonizing a sewer system, vanHAX has not become widespread across multiple taxa, remaining primarily in E. faecalis and E. faecium, with the exception of Paenibacillus.IMPORTANCELong-term colonization of microbial communities with antimicrobial-resistant bacteria is expected to result in sharing of the resistance genes between several different bacterial taxa of the communities. We investigated microbiomes from a sewer, which have been colonized with glycopeptide-resistant bacteria harboring the mobile vanHAX gene cluster for a minimum of 20 years, using metagenomics sequencing and Hi-C. We found that despite the long-term presence in the sewer, the vanHAX genes have seemingly not disseminated widely. | 2025 | 39656004 |