title: Evidence for the predominance of a single tet(M) gene sequence type in tetracycline-resistant Ureaplasma parvum and Mycoplasma hominis isolates from Tunisian patients.
abstract: Resistance to tetracyclines in genital mycoplasmas is due mainly to acquisition of the tet(M) determinant, which is frequently associated with conjugative transposon elements of the Tn916/Tn1545 family. The aim of the present work was to evaluate the prevalence of tet(M) in Tunisian isolates and to gain an insight into its origin and evolution. Twenty Ureaplasma parvum, two Ureaplasma urealyticum and 48 Mycoplasma hominis isolates, recovered from Tunisian patients with urogenital and infertility disorders, were evaluated for their resistance to tetracyclines and interrogated by PCR amplification for the presence of tet(M) and int-Tn, the gene encoding the integrase of Tn916/Tn1545-like transposons. The resistance rates to tetracyclines were 22.72 and 25.0 % among U. parvum and M. hominis isolates, respectively, with high-level resistance observed in 11 of the 12 resistant M. hominis isolates. All resistant isolates harboured both tet(M) and int-Tn sequences. Nucleotide sequence analysis of the tet(M) amplicon revealed a unique sequence shared by all tetracycline-resistant clinical isolates of both species. Molecular typing indicated that the tetracycline-resistant U. parvum and M. hominis isolates were not clonal. Taken together, these data indicate that a single tet(M) gene sequence type, most probably transmitted via a Tn916/Tn1545-like transposon, contributes to most of the tetracycline resistance in U. parvum and M. hominis isolates in Tunisia. Because this tet(M) gene sequence type was harboured by different Mycoplasma spp. and by phylogenetically distinct isolates within these species, one could reasonably argue that it may have benefited from an efficient horizontal transfer context, making it highly competent to spread.
authors.affiliation: Unit of Mycoplasmas, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, 13 Place Pasteur, B.P. 74, 1002 Tunis-Belvédère, Tunis, Tunisia.
authors.forename: Boutheina Ben Abdelmoumen
authors.initials: BBA
authors.lastname: Mardassi
authors.affiliation: Unit of Mycoplasmas, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, 13 Place Pasteur, B.P. 74, 1002 Tunis-Belvédère, Tunis, Tunisia.
authors.forename: Nadhem
authors.initials: N
authors.lastname: Aissani
authors.affiliation: Unit of Mycoplasmas, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, 13 Place Pasteur, B.P. 74, 1002 Tunis-Belvédère, Tunis, Tunisia.
authors.forename: Imed
authors.initials: I
authors.lastname: Moalla
authors.affiliation: Unit of Mycoplasmas, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, 13 Place Pasteur, B.P. 74, 1002 Tunis-Belvédère, Tunis, Tunisia.
authors.forename: Douaa
authors.initials: D
authors.lastname: Dhahri
authors.affiliation: Unit of Mycoplasmas, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, 13 Place Pasteur, B.P. 74, 1002 Tunis-Belvédère, Tunis, Tunisia.
authors.forename: Abir
authors.initials: A
authors.lastname: Dridi
authors.affiliation: Unit of Mycoplasmas, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, 13 Place Pasteur, B.P. 74, 1002 Tunis-Belvédère, Tunis, Tunisia.
authors.forename: Béhija
authors.initials: B
authors.lastname: Mlik
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics*; D004251:DNA Transposable Elements; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D009175:Mycoplasma Infections / Q000453:epidemiology / Q000382:microbiology; D019535:Mycoplasma hominis / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013752:Tetracycline / Q000494:pharmacology; D013753:Tetracycline Resistance / Q000235:genetics*; D014416:Tunisia / Q000453:epidemiology; D014509:Ureaplasma / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D016869:Ureaplasma Infections / Q000453:epidemiology / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004251:DNA Transposable Elements; C083138:Tet M resistance protein, Bacteria; D013752:Tetracycline