# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 3027 | 0 | 0.9823 | Tn5045, a novel integron-containing antibiotic and chromate resistance transposon isolated from a permafrost bacterium. A novel antibiotic and chromate resistance transposon, Tn5045, was isolated from a permafrost strain of Pseudomonas sp. Tn5045 is a compound transposon composed of three distinct genetic elements. The backbone element is a Tn1013-like Tn3 family transposon, termed Tn1013∗, that contains the tnpA and the tnpR genes, encoding the transposase and resolvase, respectively, the res-site and four genes (orfA, B, C, D) related to different house-keeping genes. The second element is class 1 integron, termed InC∗, which is inserted into the Tn1013∗ res-region and contains 5'-CS-located integrase, 3'-CS-located qacE∆1 and sulfonamide resistance sulI genes, and a single cassette encoding the streptomycin resistance aadA2-gene. The third element is a TnOtChr-like Tn3 family transposon termed TnOtChr∗, which is inserted into the transposition module of the integron and contains genes of chromate resistance (chrB, A, C, F). Tn5045 is the first example of an ancient integron-containing mobile element and also the first characterized compound transposon coding for both antibiotic and chromate, resistance. Our data demonstrate that antibiotic and chromate resistance genes were distributed in environmental bacteria independently of human activities and provide important insights into the origin and evolution of antibiotic resistance integrons. | 2011 | 21262357 |
| 530 | 1 | 0.9819 | Location of the genes for anthranilate synthase in Streptomyces venezuelae ISP5230: genetic mapping after integration of the cloned genes. The anthranilate synthase (trpEG) genes in Streptomyces venezuelae ISP5230 were located by allowing a segregationally unstable plasmid carrying cloned S. venezuelae trpEG DNA and a thiostrepton resistance (tsr) marker to integrate into the chromosome. The integrated tsr was mapped by conjugation and transduction to a location close to tyr-2, between arg-6 and trpA13. A genomic DNA fragment containing trpC from S. venezuelae ISP5230 was cloned by complementation of a trpC mutation in Streptomyces lividans. Evidence from restriction enzyme analysis of the cloned DNA fragments, from Southern hybridization using the cloned trp DNA as probes, and from cotransduction frequencies, placed trpEG at a distance of 12-45 kb from the trpCBA cluster. The overall arrangement of tryptophan biosynthesis genes in the S. venezuelae chromosome differs from that in other bacteria examined so far. | 1993 | 8515229 |
| 816 | 2 | 0.9816 | High-Level Nickel Resistance in Alcaligenes xylosoxydans 31A and Alcaligenes eutrophus KTO2. Two new nickel-resistant strains of Alcaligenes species were selected from a large number (about 400) of strains isolated from ecosystems polluted by heavy metals and were studied on the physiological and molecular level. Alcaligenes xylosoxydans 31A is a heterotrophic bacterium, and Alcaligenes eutrophus KTO2 is an autotrophic aerobic hydrogen-oxidizing bacterium. Both strains carry-among other plasmids-a megaplasmid determining resistance to 20 to 50 mM NiCl(2) and 20 mM CoCl(2) (when growing in defined Tris-buffered media). Megaplasmids pTOM8, pTOM9 from strain 31A, and pGOE2 from strain KTO2 confer nickel resistance to the same degree to transconjugants of all strains of A. eutrophus tested but were not transferred to Escherichia coli. However, DNA fragments carrying the nickel resistance genes, cloned into broad-hostrange vector pVDZ'2, confer resistance to A. eutrophus derivatives as well as E. coli. The DNA fragments of both bacteria, TBA8, TBA9, and GBA (14.5-kb BamHI fragments), appear to be identical. They share equal size, restriction maps, and strong DNA homology but are largely different from fragment HKI of nickel-cobalt resistance plasmid pMOL28 of A. eutrophus CH34. | 1991 | 16348590 |
| 823 | 3 | 0.9816 | Characterization of the prtA and prtB genes of Erwinia chrysanthemi EC16. Two tandem metalloprotease-encoding structural genes, prtA and prtB, were sequenced from Erwinia chrysanthemi EC16. These were highly homologous to previously reported genes from the same bacteria, as well as to three other metalloprotease-encoding genes from enteric bacteria. The three tandem prt structural genes from strain EC16 were closely linked to a cluster of genes previously found to be essential for extracellular secretion of the metalloproteases. | 1993 | 8224883 |
| 3015 | 4 | 0.9815 | Genetic structure and biological properties of the first ancient multiresistance plasmid pKLH80 isolated from a permafrost bacterium. A novel multidrug-resistance plasmid, pKLH80, previously isolated from Psychrobacter maritimus MR29-12 found in ancient permafrost, was completely sequenced and analysed. In our previous studies, we focused on the pKLH80 plasmid region containing streptomycin and tetracycline resistance genes, and their mobilization with an upstream-located ISPpy1 insertion sequence (IS) element. Here, we present the complete sequence of pKLH80 and analysis of its backbone genetic structure, including previously unknown features of the plasmid's accessory region, notably a novel variant of the β-lactamase gene blaRTG-6. Plasmid pKLH80 was found to be a circular 14 835 bp molecule that has an overall G+C content of 40.3 mol% and encodes 20 putative ORFs. There are two distinctive functional modules within the plasmid backbone sequence: (i) the replication module consisting of repB and the oriV region; and (ii) the mobilization module consisting of mobA, mobC and oriT. All of the aforementioned genes share sequence identities with corresponding genes of different species of Psychrobacter. The plasmid accessory region contains antibiotic resistance genes and IS elements (ISPsma1 of the IS982 family, and ISPpy1 and ISAba14 of the IS3 family) found in environmental and clinical bacterial strains of different taxa. We revealed that the sequences flanking blaRTG-6 and closely related genes from clinical bacteria are nearly identical. This fact suggests that blaRTG-6 from the environmental strain of Psychrobacter is a progenitor of blaRTG genes of clinical bacteria. We also showed that pKLH80 can replicate in different strains of Acinetobacter and Psychrobacter genera. The roles of IS elements in the horizontal transfer of antibiotic resistance genes are examined and discussed. | 2014 | 25063046 |
| 9871 | 5 | 0.9815 | An Integrative and Conjugative Element (ICE) Found in Shewanella halifaxensis Isolated from Marine Fish Intestine May Connect Genetic Materials between Human and Marine Environments. Integrative and conjugative elements (ICEs) play a role in the horizontal transfer of antibiotic resistance genes (ARGs). We herein report an ICE from Shewanella halifaxensis isolated from fish intestine with a similar structure to both a clinical bacterial ICE and marine bacterial plasmid. The ICE was designated ICEShaJpn1, a member of the SXT/R391 family of ICEs (SRIs). ICEShaJpn1 has a common core structure with SRIs of clinical and fish origins and an ARG cassette with the pAQU1 plasmid of Photobacterium damselae subsp. damselae, suggesting that the common core of SRIs is widely distributed and ARG cassettes are collected from regional bacteria. | 2022 | 36058879 |
| 483 | 6 | 0.9814 | Present-day mercury resistance transposons are common in bacteria preserved in permafrost grounds since the Upper Pleistocene. Transposons closely related to mercury resistance transposons Tn5041, Tn5053, and Tn5056, which have been previously described in present-day bacteria, were detected in a survey of 12 mercury-resistant Pseudomonas strains isolated from permafrost samples aged 15-40 thousand years. In addition, Tn5042, a novel type of mercury resistance transposon, was revealed in the permafrost strain collection and its variants found to be common among present-day bacteria. The results reveal that no drastic changes in the distribution mode of the different types of mercury resistance transposons among environmental bacteria have taken place in the last 15-40 thousand years. | 2005 | 16084067 |
| 360 | 7 | 0.9813 | Broad host range cloning vectors for gram-negative bacteria. A series of cloning vectors has been constructed based on the broad-host-range plasmid R300B. One of these vectors, pGSS33, has a size of 13.4 kb and carries four antibiotic resistance genes [ampicillin (Apr), chloramphenicol (Cmr), streptomycin (Smr) and tetracycline (Tcr)], all of which have restriction sites for insertional inactivation. The derivation, structure and uses of the plasmids are described. | 1984 | 6092235 |
| 469 | 8 | 0.9813 | Ancient permafrost staphylococci carry antibiotic resistance genes. Background: Permafrost preserves a variety of viable ancient microorganisms. Some of them can be cultivated after being kept at subzero temperatures for thousands or even millions of years. Objective: To cultivate bacterial strains from permafrost. Design: We isolated and cultivated two bacterial strains from permafrost that was obtained at Mammoth Mountain in Siberia and attributed to the Middle Miocene. Bacterial genomic DNA was sequenced with 40-60× coverage and high-quality contigs were assembled. The first strain was assigned to Staphylococcus warneri species (designated MMP1) and the second one to Staphylococcus hominis species (designated MMP2), based on the classification of 16S ribosomal RNA genes and genomic sequences. Results: Genomic sequence analysis revealed the close relation of the isolated ancient bacteria to the modern bacteria of this species. Moreover, several genes associated with resistance to different groups of antibiotics were found in the S. hominis MMP2 genome. Conclusions: These findings supports a hypothesis that antibiotic resistance has an ancient origin. The enrichment of cultivated bacterial communities with ancient permafrost strains is essential for the analysis of bacterial evolution and antibiotic resistance. | 2017 | 28959177 |
| 3039 | 9 | 0.9812 | Distinct recent lineages of the strA- strB streptomycin-resistance genes in clinical and environmental bacteria. We report the linkage of the strA-strB streptomycin-resistance genes with Class 1 integron sequences on pSTR1, a 75-kb multiple antibiotic-resistance plasmid from Shigella flexneri. strA-strB had previously been detected only within Tn 5393, a Tn 3-family transposon, and on small nonconjugative broad-host-range plasmids such as RSF1010. The geographic range of Tn 5393 was also extended to Pseudomonas spp. isolated from apple trees in New Zealand and soil in the USA. Comparative sequence analyses indicated that strA-strB from Tn 5393 and nonconjugative plasmids constitute distinct recent lineages with strA-strB from pSTR1 intermediate between the other two. The carriage of strA-strB within an integron, a transposon, and on broad-host-range plasmids has facilitated the world-wide dissemination of this determinant among at least 21 bacterial genera. | 2002 | 12029529 |
| 9945 | 10 | 0.9811 | The Ellis Island Effect: A novel mobile element in a multi-drug resistant Bacteroides fragilis clinical isolate includes a mosaic of resistance genes from Gram-positive bacteria. Objectives: Bacteroides fragilis, a Gram-negative anaerobic bacterium, is alternately a gut commensal or virulent pathogen and is an important reservoir for horizontal gene transfer (HGT) of bacterial resistance and virulence genes in the human gastrointestinal tract. We identified a unique conjugative transposon (CTn) in a multidrug resistant clinical isolate of B. fragilis (BF-HMW615); we named this element CTnHyb because it included a hybrid mosaic of foreign elements. This study reports the characterization of CTnHyb and discusses the potential impact on horizontal spread of resistance genes. Results: CTnHyb contains several efflux pump genes and several genes that confer or may confer antibiotic resistance to tetracycline, kanamycin, metronidazole and spectinomycin (truncated gene). CTnHyb also contains a mosaic of mobile elements from Gram-positive organisms. CTnHyb is easily transferred from BF-HMW615 (the original isolate) to BF638R (lab strain) and integrated into the BF638R chromosome. The "foreign" (from Gram-positive bacteria) nucleotide sequences within CTnHyb were > 99% preserved indicating that the gene acquisition from the Gram-positive bacteria was very recent. Conclusion: CTnHyb is a novel CTn residing in a multidrug resistant strain of B. fragilis. The global nature and wide phylogenetic reach of HGT means that any gene in any bacterium can potentially be mobilized. Understanding the mechanisms that drive the formation and transfer of these elements and, potentially, ways to limit the transfer are necessary to prevent a devastating spread of resistance elements. | 2014 | 25165618 |
| 3059 | 11 | 0.9811 | Genome Analysis of Kingella kingae Strain KWG1 Reveals How a β-Lactamase Gene Inserted in the Chromosome of This Species. We describe the genome of a penicillinase-producing Kingella kingae strain (KWG1), the first to be isolated in continental Europe, whose bla(TEM-1) gene was, for the first time in this species, found to be chromosomally inserted. The bla(TEM) gene is located in an integrative and conjugative element (ICE) inserted in Met-tRNA and comprising genes that encode resistance to sulfonamides, streptomycin, and tetracycline. This ICE is homologous to resistance-conferring plasmids of K. kingae and other Gram-negative bacteria. | 2016 | 26574009 |
| 493 | 12 | 0.9810 | Mercury resistance transposons of gram-negative environmental bacteria and their classification. A total of 29 mercury resistance transposons were isolated from mercury-resistant environmental strains of proteobacteria collected in different parts of Eurasia and the USA and tested for hybridization with probes specific for transposase genes of known mercury resistance transposons. 9 were related to Tn21 in this test, 12 were related to Tn5053, 4 to Tn5041 and 1 to Tn5044; three transposons were negative in this test. Restriction mapping and DNA sequencing revealed that 12 transposons were identical or nearly identical to their corresponding relatives while the rest showed varying divergence from their closest relatives. Most of these previously unknown transposons apparently arose as a result of homologous or site-specific recombination. One of these, Tn5046, was completely sequenced, and shown to be a chimera with the mer operon and the transposition module derived from the transposons related to Tn5041 and to Tn5044, respectively. Transposon Tn5070, showing no hybridization with the specific probes used in this study, was also completely sequenced. The transposition module of Tn5070 was most closely related to that of Tn3 while the mer operon was most closely related to that of plasmid pMERPH. The merR of Tn5070 is transcribed in the same direction as the mer structural genes, which is typical for mer operons of gram-positive bacteria. Our data suggest that environmental bacteria may harbor many not yet recognized mercury resistance transposons and warrant their further inventory. | 2001 | 11763242 |
| 3042 | 13 | 0.9810 | Aminoglycoside acetyltransferase 3-IV (aacC4) and hygromycin B 4-I phosphotransferase (hphB) in bacteria isolated from human and animal sources. Members of the family Enterobacteriaceae harboring an enzyme of the aminoglycoside acetyltransferase 3 class (AAC-3-IV) (apramycin and gentamicin resistance) and hygromycin B phosphotransferase 4 (HPH-4-I) (hygromycin B resistance) have been isolated from human clinical sources in Europe. A cluster of genes containing IS140, aacC4, and hphB was found in these strains. We demonstrate by Southern hybridization that this cluster is identical to the operon found in animals that also contains insertion sequences belonging to the ISO family. This provides another example of presumptive transfer of antibiotic resistance genes between bacteria of animal and human origin. | 1990 | 1963287 |
| 5187 | 14 | 0.9810 | 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 |
| 3063 | 15 | 0.9810 | Antibiotic resistance among coliform and fecal coliform bacteria isolated from the freshwater mussel Hydridella menziesii. Freshwater mussels (Hydridella menziesii) collected from Lakes Rotoroa, Rotoiti, and Brunner, South Island, New Zealand, contained coliform and fecal coliform bacteria. The majority of these bacteria were resistant to one or more antibiotics, but none transferred streptomycin, tetracycline, or kanamycin resistance to an antibiotic-susceptible strain of Escherichia coli K-12. | 1976 | 779633 |
| 5248 | 16 | 0.9808 | Antibiotic resistance of heterotrophic bacteria from the sediments of adjoining high Arctic fjords, Svalbard. Antibiotic resistance bacteria (ARB) and antibiotic resistance genes (ARGs) are now considered major global threats. The Kongsfjorden and Krossfjorden are the interlinked fjords in the Arctic that are currently experiencing the effects of climate change and receiving input of pollutants from distant and regional sources. The present study focused on understanding the prevalence of antibiotic resistance of retrievable heterotrophic bacteria from the sediments of adjacent Arctic fjords Kongsfjorden and Krossfjorden. A total of 237 bacterial isolates were tested against 16 different antibiotics. The higher resistance observed towards Extended Spectrum β-lactam antibiotic (ESBL) includes ceftazidime (45.56%) followed by trimethoprim (27%) and sulphamethizole (24.05%). The extent of resistance was meagre against tetracycline (2.53%) and gentamycin (2.95%). The 16S rRNA sequencing analysis identified that Proteobacteria (56%) were the dominant antibiotic resistant phyla, followed by Firmicutes (35%), Actinobacteria (8%) and Bacteroidetes. The dominant resistant bacterial isolates are Bacillus cereus (10%), followed by Alcaligenes faecalis (6.47%), Cytobacillus firmus (5.75%) Salinibacterium sp. (5%) and Marinobacter antarcticus (5%). Our study reveals the prevalence of antibiotic resistance showed significant differences in both the inner and outer fjords of Kongsfjorden and Krossfjorden (p < 0.05). This may be the input of antibiotic resistance bacteria released into the fjords from the preserved permafrost due to the melting of glaciers, horizontal gene transfer, and human influence in the Arctic region act as a selection pressure for the development and dissemination of more antibiotic resistant bacteria in Arctic fjords. | 2024 | 38767750 |
| 480 | 17 | 0.9807 | Permanent draft genome sequences of cadmium-resistant isolates of Cupriavidus from soils within the Tar Creek Superfund site. Soil samples taken near the abandoned town of Picher, OK, USA, were used to enrich and isolate bacteria in the presence of cadmium. Isolates reported belong to the genus Cupriavidus. Here, we report their permanent draft sequences with an emphasis on genes conferring resistance to cadmium. | 2025 | 39589146 |
| 460 | 18 | 0.9807 | Horizontal transfer of the photosynthesis gene cluster and operon rearrangement in purple bacteria. A 37-kb photosynthesis gene cluster was sequenced in a photosynthetic bacterium belonging to the beta subclass of purple bacteria (Proteobacteria), Rubrivivax gelatinosus. The cluster contained 12 bacteriochlorophyll biosynthesis genes (bch), 7 carotenoid biosynthesis genes (crt), structural genes for photosynthetic apparatuses (puf and puh), and some other related genes. The gene arrangement was markedly different from those of other purple photosynthetic bacteria, while two superoperonal structures, crtEF-bchCXYZ-puf and bchFNBHLM-lhaA-puhA, were conserved. Molecular phylogenetic analyses of these photosynthesis genes showed that the photosynthesis gene cluster of Rvi. gelatinosus was originated from those of the species belonging to the alpha subclass of purple bacteria. It was concluded that a horizontal transfer of the photosynthesis gene cluster from an ancestral species belonging to the alpha subclass to that of the beta subclass of purple bacteria had occurred and was followed by rearrangements of the operons in this cluster. | 2001 | 11343129 |
| 3017 | 19 | 0.9807 | The ancient small mobilizable plasmid pALWED1.8 harboring a new variant of the non-cassette streptomycin/spectinomycin resistance gene aadA27. The small mobilizable plasmid pALWED1.8 containing a novel variant of the streptomycin/spectinomycin resistance gene aadA27 was isolated from the permafrost strains of Acinetobacter lwoffii. The 4135bp plasmid carries mobА and mobC genes that mediate its mobilization by conjugative plasmids. The nucleotide sequences of mobА and mobC are similar to those of mobilization genes of the modern plasmid pRAY* and its variants, which contain aadB gene, and are widespread among the pathogenic strains of Acinetobacter baumannii. Almost identical pALWED1.8 variants were detected in modern environmental Аcinetobacter strains. A highly similar plasmid was revealed in a strain of Acinetobacter parvus isolated from mouse intestine. Furthermore, we discovered six previously unidentified variants of plasmids related to pALWED1.8 and pRAY* in public databases. In contrast to most known variants of aadA which are cassette genes associated with integrons, the aadA27 variant harbored by pALWED1.8 is a non-cassette, autonomously transcribed gene. Non-cassette aadA genes with 96% sequence identity to aadA27 were detected in the chromosomes of Acinetobacter gyllenbergii and several uncharacterized strains of Аcinetobacter sp. Moreover, we revealed that the autonomous aadA-like genes are present in the chromosomes of many gram-positive and gram-negative bacteria. The phylogenetic analysis of amino acid sequences of all identified AadA proteins showed the following: (i) cassette aadA genes form a separate monophyletic group and mainly reside on plasmids and (ii) chromosomal non-cassette aadA genes are extremely diverse and can be inherited both vertical and via horizontal gene transfer. | 2016 | 26896789 |