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Berglund F, Böhm ME, Martinsson A, Ebmeyer S, Österlund T, Johnning A, Larsson DGJ, Kristiansson E. Comprehensive screening of genomic and metagenomic data reveals a large diversity of tetracycline resistance genes. Microb Genom 2020; 6:mgen000455. [PMID: 33125315 PMCID: PMC7725328 DOI: 10.1099/mgen.0.000455] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 09/27/2020] [Indexed: 12/11/2022] Open
Abstract
Tetracyclines are broad-spectrum antibiotics used to prevent or treat a variety of bacterial infections. Resistance is often mediated through mobile resistance genes, which encode one of the three main mechanisms: active efflux, ribosomal target protection or enzymatic degradation. In the last few decades, a large number of new tetracycline-resistance genes have been discovered in clinical settings. These genes are hypothesized to originate from environmental and commensal bacteria, but the diversity of tetracycline-resistance determinants that have not yet been mobilized into pathogens is unknown. In this study, we aimed to characterize the potential tetracycline resistome by screening genomic and metagenomic data for novel resistance genes. By using probabilistic models, we predicted 1254 unique putative tetracycline resistance genes, representing 195 gene families (<70 % amino acid sequence identity), whereof 164 families had not been described previously. Out of 17 predicted genes selected for experimental verification, 7 induced a resistance phenotype in an Escherichia coli host. Several of the predicted genes were located on mobile genetic elements or in regions that indicated mobility, suggesting that they easily can be shared between bacteria. Furthermore, phylogenetic analysis indicated several events of horizontal gene transfer between bacterial phyla. Our results also suggested that acquired efflux pumps originate from proteobacterial species, while ribosomal protection genes have been mobilized from Firmicutes and Actinobacteria. This study significantly expands the knowledge of known and putatively novel tetracycline resistance genes, their mobility and evolutionary history. The study also provides insights into the unknown resistome and genes that may be encountered in clinical settings in the future.
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Affiliation(s)
- Fanny Berglund
- Department of Mathematical Sciences, Chalmers University of Technology and University of Gothenburg, Gothenburg, Sweden
- Centre for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
| | - Maria-Elisabeth Böhm
- Centre for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Anton Martinsson
- Department of Mathematical Sciences, Chalmers University of Technology and University of Gothenburg, Gothenburg, Sweden
- Centre for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
| | - Stefan Ebmeyer
- Centre for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Tobias Österlund
- Department of Mathematical Sciences, Chalmers University of Technology and University of Gothenburg, Gothenburg, Sweden
- Centre for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
| | - Anna Johnning
- Department of Mathematical Sciences, Chalmers University of Technology and University of Gothenburg, Gothenburg, Sweden
- Centre for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
- Department of Systems and Data Analysis, Fraunhofer-Chalmers Centre, Chalmers Science Park, Gothenburg, Sweden
| | - D. G. Joakim Larsson
- Centre for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Erik Kristiansson
- Department of Mathematical Sciences, Chalmers University of Technology and University of Gothenburg, Gothenburg, Sweden
- Centre for Antibiotic Resistance Research (CARe), University of Gothenburg, Gothenburg, Sweden
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Su JQ, Wei B, Xu CY, Qiao M, Zhu YG. Functional metagenomic characterization of antibiotic resistance genes in agricultural soils from China. ENVIRONMENT INTERNATIONAL 2014; 65:9-15. [PMID: 24412260 DOI: 10.1016/j.envint.2013.12.010] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Revised: 09/13/2013] [Accepted: 12/13/2013] [Indexed: 05/12/2023]
Abstract
Soil has been regarded as a rich source of antibiotic resistance genes (ARGs) due to the complex microbial community and diverse antibiotic-producing microbes in soil, however, little is known about the ARGs in unculturable bacteria. To investigate the diversity and distribution of ARGs in soil and assess the impact of agricultural practice on the ARGs, we screened soil metagenomic library constructed using DNA from four different agricultural soil for ARGs. We identified 45 clones conferring resistance to minocycline, tetracycline, streptomycin, gentamicin, kanamycin, amikacin, chloramphenicol and rifampicin. The similarity of identified ARGs with the closest protein in GenBank ranged from 26% to 92%, with more than 60% of identified ARGs had low similarity less than 60% at amino acid level. The identified ARGs include aminoglycoside acetyltransferase, aminoglycoside 6-adenyltransferase, ADP-ribosyl transferase, ribosome protection protein, transporters and other antibiotic resistant determinants. The identified ARGs from the soil with manure application account for approximately 70% of the total ARGs in this study, implying that manure amendment may increase the diversity of antibiotic resistance genes in soil bacteria. These results suggest that antibiotic resistance in soil remains unexplored and functional metagenomic approach is powerful in discovering novel ARGs and resistant mechanisms.
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Affiliation(s)
- Jian Qiang Su
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Bei Wei
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Chun Yan Xu
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Min Qiao
- State Key Lab of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yong Guan Zhu
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; State Key Lab of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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3
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Thaker M, Spanogiannopoulos P, Wright GD. The tetracycline resistome. Cell Mol Life Sci 2010; 67:419-31. [PMID: 19862477 PMCID: PMC11115633 DOI: 10.1007/s00018-009-0172-6] [Citation(s) in RCA: 212] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Revised: 09/24/2009] [Accepted: 10/05/2009] [Indexed: 11/27/2022]
Abstract
Resistance to tetracycline emerged soon after its discovery six decades ago. Extensive clinical and non-clinical uses of this class of antibiotic over the years have combined to select for a large number of resistant determinants, collectively termed the tetracycline resistome. In order to impart resistance, microbes use different molecular mechanisms including target protection, active efflux, and enzymatic degradation. A deeper understanding of the structure, mechanism, and regulation of the genes and proteins associated with tetracycline resistance will contribute to the development of tetracycline derivatives that overcome resistance. Newer generations of tetracyclines derived from engineering of biosynthetic genetic programs, semi-synthesis, and in particular recent developments in their chemical synthesis, together with a growing understanding of resistance, will serve to retain this class of antibiotic to combat pathogens.
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Affiliation(s)
- Maulik Thaker
- Department of Biochemistry and Biomedical Sciences, Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, 1200 Main St W, Hamilton, Canada
| | - Peter Spanogiannopoulos
- Department of Biochemistry and Biomedical Sciences, Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, 1200 Main St W, Hamilton, Canada
| | - Gerard D. Wright
- Department of Biochemistry and Biomedical Sciences, Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, 1200 Main St W, Hamilton, Canada
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Petković H, Cullum J, Hranueli D, Hunter IS, Perić-Concha N, Pigac J, Thamchaipenet A, Vujaklija D, Long PF. Genetics of Streptomyces rimosus, the oxytetracycline producer. Microbiol Mol Biol Rev 2006; 70:704-28. [PMID: 16959966 PMCID: PMC1594589 DOI: 10.1128/mmbr.00004-06] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
From a genetic standpoint, Streptomyces rimosus is arguably the best-characterized industrial streptomycete as the producer of oxytetracycline and other tetracycline antibiotics. Although resistance to these antibiotics has reduced their clinical use in recent years, tetracyclines have an increasing role in the treatment of emerging infections and noninfective diseases. Procedures for in vivo and in vitro genetic manipulations in S. rimosus have been developed since the 1950s and applied to study the genetic instability of S. rimosus strains and for the molecular cloning and characterization of genes involved in oxytetracycline biosynthesis. Recent advances in the methodology of genome sequencing bring the realistic prospect of obtaining the genome sequence of S. rimosus in the near term.
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Affiliation(s)
- Hrvoje Petković
- Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
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Nikolakopoulou TL, Egan S, van Overbeek LS, Guillaume G, Heuer H, Wellington EMH, van Elsas JD, Collard JM, Smalla K, Karagouni AD. PCR detection of oxytetracycline resistance genes otr(A) and otr(B) in tetracycline-resistant streptomycete isolates from diverse habitats. Curr Microbiol 2005; 51:211-6. [PMID: 16132462 DOI: 10.1007/s00284-004-4430-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2004] [Accepted: 09/04/2004] [Indexed: 11/28/2022]
Abstract
A range of European habitats was screened by PCR for detection of the oxytetracycline resistance genes otr(A) and otr(B), found in the oxytetracycline-producing strain Streptomyces rimosus. Primers were developed to detect these otr genes in tetracycline-resistant (Tc(R)) streptomycete isolates from environmental samples. Samples were obtained from bulk and rhizosphere soil, manure, activated sludge and seawater. The majority of Tc(R) streptomycetes originated from bulk and rhizosphere soil. Fewer Tc(R) streptomycetes were isolated from manure and seawater and none from sewage. By PCR, three out of 217 isolates were shown to contain the otr(A) gene and 13 out of 217 the otr(B) gene. Surprisingly, these genes were detected in taxonomic groups not known as tetracycline-producing strains. The majority of the otr gene-carrying strains was assigned to S. exfoliatus or S. rochei and originated from all habitats from which Tc(R) streptomycetes were obtained. Our results indicated that the occurrence of otr(A) and otr(B) genes in natural environments was limited and that otr(B), in comparison to otr(A), seemed to be more common.
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Affiliation(s)
- Theodora L Nikolakopoulou
- Department of Botany, Microbiology Group, National and Kapodistrian University of Athens, Faculty of Biology, Greece
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6
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Roberts MC. Resistance to tetracycline, macrolide-lincosamide-streptogramin, trimethoprim, and sulfonamide drug classes. Mol Biotechnol 2002; 20:261-83. [PMID: 11936257 DOI: 10.1385/mb:20:3:261] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The discovery and use of antimicrobial agents in the last 50 yr has been one of medicine's greatest achievements. These agents have reduced morbidity and mortality of humans and animals and have directly contributed to human's increased life span. However, bacteria are becoming increasingly resistant to these agents by mutations, which alter existing bacterial proteins, and/or acquisition of new genes, which provide new proteins. The latter are often associated with mobile elements that can be exchanged quickly across bacterial populations and may carry multiple antibiotic genes for resistance. In some case, virulence factors are also found on these same mobile elements. There is mounting evidence that antimicrobial use in agriculture, both plant and animal, and for environmental purposes does influence the antimicrobial resistant development in bacteria important in humans and in reverse. In this article, we will examine the genes which confer resistance to tetracycline, macrolide-lincosamide-streptogramin (MLS), trimethoprim, and sulfonamide.
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Affiliation(s)
- Marilyn C Roberts
- Department of Pathobiology, School of Public Health and Community Medicine, University of Washington, Seattle 98195, USA.
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7
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Chopra I, Roberts M. Tetracycline antibiotics: mode of action, applications, molecular biology, and epidemiology of bacterial resistance. Microbiol Mol Biol Rev 2001; 65:232-60 ; second page, table of contents. [PMID: 11381101 PMCID: PMC99026 DOI: 10.1128/mmbr.65.2.232-260.2001] [Citation(s) in RCA: 2458] [Impact Index Per Article: 106.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Tetracyclines were discovered in the 1940s and exhibited activity against a wide range of microorganisms including gram-positive and gram-negative bacteria, chlamydiae, mycoplasmas, rickettsiae, and protozoan parasites. They are inexpensive antibiotics, which have been used extensively in the prophlylaxis and therapy of human and animal infections and also at subtherapeutic levels in animal feed as growth promoters. The first tetracycline-resistant bacterium, Shigella dysenteriae, was isolated in 1953. Tetracycline resistance now occurs in an increasing number of pathogenic, opportunistic, and commensal bacteria. The presence of tetracycline-resistant pathogens limits the use of these agents in treatment of disease. Tetracycline resistance is often due to the acquisition of new genes, which code for energy-dependent efflux of tetracyclines or for a protein that protects bacterial ribosomes from the action of tetracyclines. Many of these genes are associated with mobile plasmids or transposons and can be distinguished from each other using molecular methods including DNA-DNA hybridization with oligonucleotide probes and DNA sequencing. A limited number of bacteria acquire resistance by mutations, which alter the permeability of the outer membrane porins and/or lipopolysaccharides in the outer membrane, change the regulation of innate efflux systems, or alter the 16S rRNA. New tetracycline derivatives are being examined, although their role in treatment is not clear. Changing the use of tetracyclines in human and animal health as well as in food production is needed if we are to continue to use this class of broad-spectrum antimicrobials through the present century.
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Affiliation(s)
- I Chopra
- Antimicrobial Research Centre and Division of Microbiology, School of Biochemistry & Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
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8
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Chopra I, Roberts M. Tetracycline antibiotics: mode of action, applications, molecular biology, and epidemiology of bacterial resistance. Microbiol Mol Biol Rev 2001. [PMID: 11381101 DOI: 10.1016/s0022-3093(98)00783-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2023] Open
Abstract
Tetracyclines were discovered in the 1940s and exhibited activity against a wide range of microorganisms including gram-positive and gram-negative bacteria, chlamydiae, mycoplasmas, rickettsiae, and protozoan parasites. They are inexpensive antibiotics, which have been used extensively in the prophlylaxis and therapy of human and animal infections and also at subtherapeutic levels in animal feed as growth promoters. The first tetracycline-resistant bacterium, Shigella dysenteriae, was isolated in 1953. Tetracycline resistance now occurs in an increasing number of pathogenic, opportunistic, and commensal bacteria. The presence of tetracycline-resistant pathogens limits the use of these agents in treatment of disease. Tetracycline resistance is often due to the acquisition of new genes, which code for energy-dependent efflux of tetracyclines or for a protein that protects bacterial ribosomes from the action of tetracyclines. Many of these genes are associated with mobile plasmids or transposons and can be distinguished from each other using molecular methods including DNA-DNA hybridization with oligonucleotide probes and DNA sequencing. A limited number of bacteria acquire resistance by mutations, which alter the permeability of the outer membrane porins and/or lipopolysaccharides in the outer membrane, change the regulation of innate efflux systems, or alter the 16S rRNA. New tetracycline derivatives are being examined, although their role in treatment is not clear. Changing the use of tetracyclines in human and animal health as well as in food production is needed if we are to continue to use this class of broad-spectrum antimicrobials through the present century.
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Affiliation(s)
- I Chopra
- Antimicrobial Research Centre and Division of Microbiology, School of Biochemistry & Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
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9
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Aminov RI, Garrigues-Jeanjean N, Mackie RI. Molecular ecology of tetracycline resistance: development and validation of primers for detection of tetracycline resistance genes encoding ribosomal protection proteins. Appl Environ Microbiol 2001; 67:22-32. [PMID: 11133424 PMCID: PMC92507 DOI: 10.1128/aem.67.1.22-32.2001] [Citation(s) in RCA: 432] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Phylogenetic analysis of tetracycline resistance genes encoding the ribosomal protection proteins (RPPs) revealed the monophyletic origin of these genes. The most deeply branching class, exemplified by tet and otrA, consisted of genes from the antibiotic-producing organisms Streptomyces rimosus and Streptomyces lividans. With a high degree of confidence, the corresponding genes of the other seven classes (Tet M, Tet S, Tet O, Tet W, Tet Q, Tet T, and TetB P) formed phylogenetically distinct separate clusters. Based on this phylogenetic analysis, a set of PCR primers for detection, retrieval, and sequence analysis of the corresponding gene fragments from a variety of bacterial and environmental sources was developed and characterized. A pair of degenerate primers targeted all tetracycline resistance genes encoding RPPs except otrA and tet, and seven other primer pairs were designed to target the specific classes. The primers were used to detect the circulation of these genes in the rumina of cows, in swine feed and feces, and in swine fecal streptococci. Classes Tet O and Tet W were found in the intestinal contents of both animals, while Tet M was confined to pigs and Tet Q was confined to the rumen. The tet(O) and tet(W) genes circulating in the microbiota of the rumen and the gastrointestinal tract of pigs were identical despite the differences in animal hosts and antibiotic use regimens. Swine fecal streptococci uniformly possessed the tet(O) gene, and 22% of them also carried tet(M). This population could be considered one of the main reservoirs of these two resistance genes in the pig gastrointestinal tract. All classes of RPPs except Tet T and TetB P were found in the commercial components of swine feed. This is the first demonstration of the applicability of molecular ecology techniques to estimation of the gene pool and the flux of antibiotic resistance genes in production animals.
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Affiliation(s)
- R I Aminov
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
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Widdowson CA, Klugman KP. The molecular mechanisms of tetracycline resistance in the pneumococcus. Microb Drug Resist 2000; 4:79-84. [PMID: 9533730 DOI: 10.1089/mdr.1998.4.79] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Tetracycline resistance in the pneumococcus is a result of the acquisition of one of two resistance determinants, tet(M) or tet(O). These genes encode ribosomal protection proteins that have homology to the elongation factors G and Tu. Tet(M) and Tet(O) both have GTPase activity that appears to be important in the displacement of tetracycline from the ribosome. Modification of tRNA may also be important for tetracycline resistance. Transcription of tet(M) is thought to be regulated by transcriptional attenuation. Transcription of tet(O) is constitutive, however, upstream of the gene are sequences that also appear to be involved in transcriptional attenuation. tet(M) is transferred on the conjugative transposons, Tn1545 and Tn5151. It is not yet known whether tet(O) is transported on transposons or plasmids, or whether it is chromosomally integrated, in pneumococci.
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Affiliation(s)
- C A Widdowson
- South African Institute for Medical Research and the University of Witwatersrand, Department of Clinical Microbiology and Infectious Diseases, Johannesburg
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Levy SB, McMurry LM, Barbosa TM, Burdett V, Courvalin P, Hillen W, Roberts MC, Rood JI, Taylor DE. Nomenclature for new tetracycline resistance determinants. Antimicrob Agents Chemother 1999; 43:1523-4. [PMID: 10348788 PMCID: PMC89314 DOI: 10.1128/aac.43.6.1523] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Letters of the English alphabet have heretofore been used to name tetracycline resistance determinants. Since all 26 letters have now been used, a nomenclature employing numerals is recommended for future determinants, and one laboratory has offered to coordinate the assignment of numerals.
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Affiliation(s)
- S B Levy
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA.
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12
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von der Haar B, Walter S, Schwäpenheer S, Schrempf H. A novel fusidic acid resistance gene from Streptomyces lividans 66 encodes a highly specific esterase. MICROBIOLOGY (READING, ENGLAND) 1997; 143 ( Pt 3):867-874. [PMID: 9084170 DOI: 10.1099/00221287-143-3-867] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Resistance to fusidic acid in Streptomyces lividans is due to secretion of an extracellular enzyme (FusH) that converts the steroid antibiotic into an inactive derivative. NH2-terminal and several internal amino acid sequences were prepared from the purified enzyme. Using one of the deduced oligonucleotides to probe a subgenomic DNA library, the fusH gene was cloned and sequenced. Sequence analysis located an ORF which, owing to the presence of two putative start codons, indicates a predicted protein with 520 or 509 amino acids. A signal peptide was identified by aligning the deduced amino acids with the N-terminal sequence determined for the mature enzyme. The C-terminal part of the deduced FusH contains a region of three tandemly repeated stretches of 50 amino acids, which is preceded and followed by amino acids showing high homology with the repeats. FusH was found to share a GDS motif with some deduced esterases. S. lividans transformants carrying fusH on a multicopy vector synthesized high levels of FusH. Purified FusH cleaved equally well an acetyl, a thioacetyl or a formyl group from the 16 beta-position of fusidic acid and its derivatives. However, a propionyl group at the 16 beta-position was attacked with difficulty and a 16 alpha-acetyl group was not hydrolysed at all. These data indicate that FusH is a highly specific esterase. The fusH gene is widely distributed among streptomycetes that modify fusidic acid to its inactive lactone derivative.
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Affiliation(s)
- Beate von der Haar
- Universitt Osnabrück, FB Biologie/Chemie, Barbarastraße 11, 49069 Osnabrück, Germany
| | - Stefan Walter
- Universitt Osnabrück, FB Biologie/Chemie, Barbarastraße 11, 49069 Osnabrück, Germany
| | - Susanne Schwäpenheer
- Universitt Osnabrück, FB Biologie/Chemie, Barbarastraße 11, 49069 Osnabrück, Germany
| | - Hildgund Schrempf
- Universitt Osnabrück, FB Biologie/Chemie, Barbarastraße 11, 49069 Osnabrück, Germany
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Clermont D, Chesneau O, De Cespédès G, Horaud T. New tetracycline resistance determinants coding for ribosomal protection in streptococci and nucleotide sequence of tet(T) isolated from Streptococcus pyogenes A498. Antimicrob Agents Chemother 1997; 41:112-6. [PMID: 8980765 PMCID: PMC163670 DOI: 10.1128/aac.41.1.112] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
An approach based on PCR has been developed to identify new members of the tet gene family in streptococci resistant to tetracycline and minocycline. Degenerate primers, corresponding to portions of the conserved domains of the proteins Tet(M), Tet(O), TeTB(P), Tet(Q), and Tet(S), all specifying the tetracycline-minocycline resistance phenotype, were used to selectively amplify DNA fragments within the coding sequences. Nine streptococcal strains which do not carry the genes tet(M), tet(O), tetB(P), tet(Q), or tet(S) were investigated. Four of them gave no detectable PCR products. The five remaining strains each yielded a PCR product of 1.1 kbp. DNA hybridization experiments showed that these putative Tet determinants fell into four new hybridization classes, of which one, Tet T, was further analyzed. The gene tet(T) was isolated from Streptococcus pyogenes A498, and the nucleotide sequence that was necessary and sufficient for the expression of tetracycline resistance in Escherichia coli was determined. The deduced Tet(T) protein consists of 651 amino acids. The protein most closely related to Tet(T) was Tet(Q), which has 49% identical amino acid residues. A phylogenetic analysis revealed that Tet T represents a novel branching order among the Tet determinants so far described.
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Affiliation(s)
- D Clermont
- Laboratoire des Staphylocoques et des Streptocoques, Institut Pasteur, Paris, France
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14
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Roberts MC. Tetracycline resistance determinants: mechanisms of action, regulation of expression, genetic mobility, and distribution. FEMS Microbiol Rev 1996; 19:1-24. [PMID: 8916553 DOI: 10.1111/j.1574-6976.1996.tb00251.x] [Citation(s) in RCA: 345] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Tetracycline-resistant bacteria were first isolated in 1953 from Shigella dysenteriae, a bacterium which causes bacterial dysentery. Since then tetracycline-resistant bacterial have been found in increasing numbers of species and genera. This has resulted in reduced effectiveness of tetracycline therapy over time. Tetracycline resistance is normally due to the acquisition of new genes often associated with either a mobile plasmid or a transposon. These tetracycline resistance determinants are distinguishable both genetically and biochemically. Resistance is primarily due to either energy-dependent efflux of tetracycline or protection of the ribosomes from the action of tetracycline. Gram-negative tetracycline efflux proteins are linked to repressor proteins which in the absence of tetracycline block transcription of the repressor and structural efflux genes. In contrast, expression of the Gram-positive tetracycline efflux genes and some of the ribosomal protection genes appears to be regulated by attenuation of mRNA transcription. Specific tetracycline resistance genes have been identified in 32 Gram-negative and 22 Gram-positive genera. Tetracycline-resistant bacteria are found in pathogens, opportunistic and normal flora species. Tetracycline-resistant bacteria can be isolated from man, animals, food, and the environment. The nonpathogens in each of these ecosystems may play an important role as reservoirs for the antibiotic resistance genes. It is clear that if we are to reverse the trend toward increasingly antibiotic-resistant pathogenic bacteria we will need to change how antibiotics are used in both human and animal health and food production.
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Affiliation(s)
- M C Roberts
- Department of Pathobiology, School of Public Health and Community Medicine, University of Washington, Seattle 98195-7238, USA.
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15
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Fröhlich KU, Kannwischer R, Rüdiger M, Mecke D. Pentalenolactone-insensitive glyceraldehyde-3-phosphate dehydrogenase from Streptomyces arenae is closely related to GAPDH from thermostable eubacteria and plant chloroplasts. Arch Microbiol 1996; 165:179-86. [PMID: 8599535 DOI: 10.1007/bf01692859] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Streptomyces arenae produces the antibiotic pentalenolactone, a highly specific inhibitor of glyceraldehyde-3-phosphate dehydrogenase (GAPDH). During the phase of pentalenolactone production, S. arenae expresses a pentalenolactone-insensitive GAPDH isoform; otherwise, a pentalenolactone-sensitive form is expressed. The gene of the pentalenolactone-insensitive GAPDH was cloned and sequenced. Regulatory elements typical for genes encoding antibiotic resistance and production are localized upstream and downstream of the open reading frame. No expression of pentalenolactone-insensitive GAPDH was detected in Streptomyces lividans transformed with the gene. In Escherichia coli, the gene was expressed from an induced lac promoter. Amino-terminal sequencing of the heterologously expressed GAPDH proved its identity with pentalenolactone-insensitive GAPDH from S. arenae. Sequence comparisons with GAPDH from other organisms showed a close relationship to GAPDH of plant chloroplasts, of other gram-positive bacteria, and of thermophilic gram-negative bacteria. Pentalenolactone-insensitive GAPDH differs from all closely related GAPDHs only in a few residues, none of which are directly involved in catalysis or substrate binding. The total amino acid composition is more similar to GAPDH of thermophilic species than to that of mesophilic species. The purified enzyme was moderately thermotolerant, which could be a side effect of the structural changes causing pentalenolactone-resistance.
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Affiliation(s)
- K U Fröhlich
- Physiologisch-chemisches Institut, Universität Tübingen, Hoppe-Seyler-Strasse 4, D-72076 Tübingen, Germany
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Abstract
Resistance to tetracycline is generally due either to energy-dependent efflux of tetracycline or to protection of the bacterial ribosomes from the action of tetracycline. The genes that encode this resistance are normally acquired via transferable plasmids and/or transposons. Tet determinants have been found in a wide range of Gram-positive and Gram-negative bacteria and have reduced the effectiveness of therapy with tetracycline.
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Affiliation(s)
- M C Roberts
- Dept of Pathobiology, School of Public Health and Community Medicine, University of Washington, Seattle 98195
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Pang Y, Brown BA, Steingrube VA, Wallace RJ, Roberts MC. Tetracycline resistance determinants in Mycobacterium and Streptomyces species. Antimicrob Agents Chemother 1994; 38:1408-12. [PMID: 8092846 PMCID: PMC188220 DOI: 10.1128/aac.38.6.1408] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Two of seven tetracycline-resistant (Tcr) Mycobacterium fortuitum group isolates and six Tcr clinical Streptomyces isolates carried gram-positive Tcr determinants (Tet K and Tet L) and Streptomyces resistance determinants (Otr A, Otr B, and Otr C). This represents the first documentation of the acquisition by mycobacteria of determinants coding for antibiotic resistance and suggests the potential for the spread of antibiotic resistance determinants within mycobacterial species.
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Affiliation(s)
- Y Pang
- Department of Pathobiology, University of Washington, Seattle 98195
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Schlochtermeier A, Walter S, Schröder J, Moorman M, Schrempf H. The gene encoding the cellulase (Avicelase) Cel1 from Streptomyces reticuli and analysis of protein domains. Mol Microbiol 1992; 6:3611-21. [PMID: 1282194 DOI: 10.1111/j.1365-2958.1992.tb01797.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Streptomyces reticuli produces an unusual cellulase (Avicelase), with an apparent molecular weight of 82 kDa, which is solely sufficient to degrade crystalline cellulose. During cultivation the processing of the Avicelase to a truncated enzyme (42 kDa) and an inactive protein (40 kDa) correlated with the occurrence of an extracellular protease. After its purification this 36 kDa protease cleaved the S. reticuli Avicelase in vitro in the same manner. Using antibodies raised against the Avicelase and its truncated form (42 kDa) and gene libraries of S. reticuli DNA in the Escherichia coli phage vectors lambda gt11 and Charon 35, the Avicelase gene (cel1) was identified. Further subcloning and DNA-sequencing revealed a G+C rich (72%) reading frame of 2238 bp encoding a protein of 746 amino acids. The transcriptional start site was mapped about 180 bp upstream from the GTG start codon. A signal sequence of 29 amino acids was identified by aligning the deduced amino acids with the characterized N-terminus of the 82 kDa Avicelase. Comparison of the N-terminal amino acids from the purified proteins with the amino acid sequence derived from the Avicelase gene revealed that the truncated enzyme (42 kDa) corresponds to the C-terminal region whereas the inactive proteolytically derived protein (40 kDa) represents the N-terminal part of the 82 kDa Avicelase. Comparisons with amino acid sequences deduced from known cellulase genes indicated the presence of three putative protein domains: (i) an N-terminal part showing significant similarity with a repeat region of endoglucanase C from Cellulomonas fimi, recently shown to be a cellulose-binding domain; (ii) an adjoining region sharing homology with the N-terminal domains with unknown function of endoglucanase A from Pseudomonas fluorescens, endoglucanase D from Clostridium thermocellum and a cellodextrinase from Butyrivibrio fibrisolvens, and (iii) a C-terminal catalytic domain belonging to cellulase family E.
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