Tet 42, a Novel Tetracycline Resistance Determinant Isolated from Deep Terrestrial Subsurface Bacteria

ABSTRACT Tet 42, a novel tetracycline resistance determinant from deep subsurface bacteria, was characterized and found to have a 30% sequence similarity to TetA(Z). The protein is a putative efflux pump that shares characteristics with previously characterized pumps, including a divergently transcribed TetR repressor, a conserved GxxSDRxGRR motif, and transmembrane domains.

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Novel Tetracycline Resistance Determinant Isolated from an Environmental Strain of Serratia marcescens

Applied and Environmental Microbiology ◽

10.1128/aem.02511-06 ◽

2007 ◽

Vol 73 (7) ◽

pp. 2199-2206 ◽

Cited By ~ 38

Author(s):

Stuart A. Thompson ◽

Elizabeth V. Maani ◽

Angela H. Lindell ◽

Catherine J. King ◽

J. Vaun McArthur

Keyword(s):

Serratia Marcescens ◽

Efflux Pump ◽

Tetracycline Resistance ◽

Amino Acid Identity ◽

Resistance Determinant ◽

Mercury Resistance ◽

Resistance Locus ◽

Environmental Strain ◽

Apparent Lack ◽

E Coli

ABSTRACT Resistances to tetracycline and mercury were identified in an environmental strain of Serratia marcescens isolated from a stream highly contaminated with heavy metals. As a step toward addressing the mechanisms of coselection of heavy metal and antibiotic resistances, the tetracycline resistance determinant was cloned in Escherichia coli. Within the cloned 13-kb segment, the tetracycline resistance locus was localized by deletion analysis and transposon mutagenesis. DNA sequence analysis of an 8.0-kb region revealed a novel gene [tetA(41)] that was predicted to encode a tetracycline efflux pump. Phylogenetic analysis showed that the TetA(41) protein was most closely related to the Tet(39) efflux protein of Acinetobacter spp. yet had less than 80% amino acid identity with known tetracycline efflux pumps. Adjacent to the tetA(41) gene was a divergently transcribed gene [tetR(41)] predicted to encode a tetracycline-responsive repressor protein. The tetA(41)-tetR(41) intergenic region contained putative operators for TetR(41) binding. The tetA(41) and tetR(41) promoters were analyzed using lacZ fusions, which showed that the expression of both the tetA(41) and tetR(41) genes exhibited TetR(41)-dependent regulation by subinhibitory concentrations of tetracycline. The apparent lack of plasmids in this S. marcescens strain, as well as the presence of metabolic genes adjacent to the tetracycline resistance locus, suggested that the genes were located on the S. marcescens chromosome and may have been acquired by transduction. The cloned Tet 41 determinant did not confer mercury resistance to E. coli, confirming that Tet 41 is a tetracycline-specific efflux pump rather than a multidrug transporter.

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Burkholderia ubonensis high-level tetracycline resistance is due to efflux pump synergy involving a novel TetA(64) resistance determinant

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01767-20 ◽

2020 ◽

pp. AAC.01767-20

Author(s):

Nawarat Somprasong ◽

Carina M. Hall ◽

Jessica R. Webb ◽

Jason W. Sahl ◽

David M. Wagner ◽

...

Keyword(s):

Burkholderia Cepacia ◽

Efflux Pump ◽

Tetracycline Resistance ◽

Major Facilitator Superfamily ◽

Resistance Determinant ◽

Chromosome 1 ◽

Human Pathogens ◽

Clinically Significant ◽

Major Facilitator ◽

High Level

Burkholderia ubonensis, a non-pathogenic soil bacterium belonging to the Burkholderia cepacia complex (Bcc), is highly resistant to some clinically significant antibiotics. The concern is that B. ubonensis may serve as a resistance reservoir for Bcc or B. pseudomallei complex (Bpc) organisms that are opportunistic human pathogens. Using a B. ubonensis strain highly resistant to tetracycline (MIC ≥256 μg/ml), we identified and characterized tetA(64) that encodes a novel tetracycline-specific efflux pump of the major facilitator superfamily. TetA(64) and associated TetR(64) regulator expression is induced by tetracyclines. Although TetA(64) is the primary tetracycline and doxycycline resistance determinant, maximum tetracycline and doxycycline resistance requires synergy between TetA(64) and the non-specific AmrAB-OprA resistance nodulation cell division efflux pump. TetA(64) does not efflux minocycline, tigecycline and eravacycline. Comprehensive screening of genome sequences showed that TetA(64) is unequally distributed in the Bcc and absent from the Bpc. It is present in some major cystic fibrosis pathogens, like B. cenocepacia, but absent from others like B. multivorans. The tetR(64)-tetA(64) genes are located in a region of chromosome 1 that is highly conserved in Burkholderia. Because there is no evidence for transposition, the tetR(64)-tetA(64) genes may have been acquired by homologous recombination after horizontal gene transfer. Although Burkholderia species contain a resident multi-component efflux pump that allows them to respond to tetracyclines up to a certain concentration, the acquisition of the single-component TetA(64) by some species likely provides the synergy that these bacteria need to defend against high tetracycline concentrations in niche environments.

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Identification and Transferability of Tetracycline Resistance in Streptococcus thermophilus during Milk Fermentation, Storage, and Gastrointestinal Transit

Fermentation ◽

10.3390/fermentation7020065 ◽

2021 ◽

Vol 7 (2) ◽

pp. 65

Author(s):

Armin Tarrah ◽

Shadi Pakroo ◽

Viviana Corich ◽

Alessio Giacomini

Keyword(s):

Efflux Pump ◽

Acquired Resistance ◽

Gastrointestinal Transit ◽

Tetracycline Resistance ◽

Lactobacillus Delbrueckii ◽

Genomic Islands ◽

Resistant Bacteria ◽

Human Pathogens ◽

Resistance Level ◽

Milk Fermentation

The existence of antibiotic-resistant bacteria in food products, particularly those carrying acquired resistance genes, has increased concerns about the transmission of these genes from beneficial microbes to human pathogens. In this study, we evaluated the antibiotic resistance-susceptibility patterns of 16 antibiotics in eight S. thermophilus strains, whose genome sequence is available, using phenotypic and genomic approaches. The minimal inhibitory concentration values collected revealed intermediate resistance to aminoglycosides, whereas susceptibility was detected for different classes of β-lactams, quinolones, glycopeptide, macrolides, and sulfonamides in all strains. A high tetracycline resistance level has been detected in strain M17PTZA496, whose genome analysis indicated the presence of the tet(S) gene and the multidrug and toxic compound extrusion (MATE) family efflux pump. Moreover, an in-depth genomic analysis revealed genomic islands and an integrative and mobilizable element (IME) in the proximity of the gene tet(S). However, despite the presence of a prophage, genomic islands, and IME, no horizontal gene transfer was detected to Lactobacillus delbrueckii subsp. lactis DSM 20355 and Lactobacillusrhamnosus GG during 24 h of skim milk fermentation, 2 weeks of refrigerated storage, and 4 h of simulated gastrointestinal transit.

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Characterization and expression of a cloned tetracycline resistance determinant from Campylobacter jejuni plasmid pUA466.

Journal of Bacteriology ◽

10.1128/jb.169.7.2984-2989.1987 ◽

1987 ◽

Vol 169 (7) ◽

pp. 2984-2989 ◽

Cited By ~ 35

Author(s):

D E Taylor ◽

K Hiratsuka ◽

H Ray ◽

E K Manavathu

Keyword(s):

Campylobacter Jejuni ◽

Tetracycline Resistance ◽

Resistance Determinant

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Distribution of the tetracycline resistance determinant tetQ gene in oral isolates of black-pigmented anaerobes in Japan

Oral Microbiology and Immunology ◽

10.1034/j.1399-302x.2001.160405.x ◽

2001 ◽

Vol 16 (4) ◽

pp. 224-228 ◽

Cited By ~ 10

Author(s):

M. Okamoto ◽

K. Takano ◽

N. Maeda

Keyword(s):

Tetracycline Resistance ◽

Resistance Determinant

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Detection of efflux pump genes in multiresistant Acinetobacter baumannii ST2 in Iran

Acta Microbiologica et Immunologica Hungarica ◽

10.1556/030.2021.01314 ◽

2021 ◽

Author(s):

Zahra Meshkat ◽

Himen Salimizand ◽

Yousef Amini ◽

Davood Mansury ◽

Abolfazl Rafati Zomorodi ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Resistance Genes ◽

Efflux Pump ◽

Tetracycline Resistance ◽

Genomic Diversity ◽

Expression Level ◽

Tetracycline Resistance Genes ◽

Microdilution Method ◽

Relationship Of ◽

Repetitive Extragenic Palindromic Pcr

AbstractAcinetobacter baumannii, as a nosocomial pathogen has become a worldwide concern in recent years. In the current study, the resistance to tetracyclines and colistin were assessed in the isolates from different provinces of Iran.During the timeline of this study, a number of 270 isolates of A. baumannii were collected from tracheal aspirates, wounds, urine and blood cultures. The minimum inhibitory concentration (MIC) for tetracycline, doxycycline, minocycline, tigecycline and colistin were evaluated. Tetracycline resistance genes were assessed by PCR. The mean expression level of adeB, adeJ and adeG were assessed using semi quantitative Real-Time PCR. The clonal relationship of the isolates was evaluated by the repetitive extragenic palindromic PCR (REP-PCR), International Clonal (IC) Lineage Multiplex PCR and multilocus sequence typing (MLST) (Pasteur scheme) methods.The MIC by microdilution method showed that 87.5, 51.4, 28, 0.74 and 0% of the isolates were resistant to tetracycline, doxycycline, minocycline, tigecycline and colistin respectively. The prevalence of tetracycline resistance genes was 99.2, 99.2, 98, 86.7, 10, 3.33, 0.37, 0% for adeB, adeJ, adeG, tetB, tetA(39), tetA, tetM and tetH in tetracycline-resistant isolates. Moreover, the expression level of adeB, adeJ, adeG genes in tigecycline-nonsusceptible A. baumannii (TNAB) strain was higher compared to the tigecycline-susceptible A. baumannii (TSAB). A broad genomic diversity was revealed, but ST2 was the most prevalent ST. Our results indicated that tetracycline resistance in Iran is mediated by resistance-nodulation-cell division (RND) and tetB efflux pumps.

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Novel Tetracycline Resistance Determinant from the Oral Metagenome

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.47.4.1430-1432.2003 ◽

2003 ◽

Vol 47 (4) ◽

pp. 1430-1432 ◽

Cited By ~ 84

Author(s):

M. L. Diaz-Torres ◽

R. McNab ◽

D. A. Spratt ◽

A. Villedieu ◽

N. Hunt ◽

...

Keyword(s):

Resistance Gene ◽

Tetracycline Resistance ◽

Resistance Determinant ◽

Tetracycline Resistance Gene ◽

Major Drawback

ABSTRACT A major drawback of most studies on how bacteria become resistant to antibiotics is that they concentrate mainly on bacteria that can be cultivated in the laboratory. In the present study, we cloned part of the oral metagenome and isolated a novel tetracycline resistance gene, tet(37), which inactivates tetracycline.

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