Diversity of structures carrying the aac(6')-aph(2") gene in clinical Enterococcus faecalis and Enterococcus faecium strains isolated in Tunisia.
The diversity of structures carrying the aac(6')-aph(2") gene was studied in 46 high-level gentamicin-resistant Enterococcus faecalis and Enterococcus faecium clinical strains recovered in a Tunisian hospital during the period 2000-2003. The inclusion of the aac(6')-aph(2") gene within the Tn4001 composite element or in its truncated forms (lacking the IS256 at the right, the left or at both sides of the aac(6')-aph(2") gene) was investigated by PCR and sequencing. The aac(6')-aph(2") gene was included in the composite Tn4001 element in 19 of 34 high-level gentamicin-resistant E. faecalis strains (56%) and in 1 of 12 E. faecium strains (12%). A truncated form of Tn4001 lacking IS256 at the left-hand (in 10 E. faecalis and 8 E. faecium), at the right-hand (3 E. faecalis and 2 E. faecium) or at both sides of the aac(6')-aph(2") gene (in 2 E. faecalis and 1 E. faecium) was also detected in 26 of our enterococci. The transference by conjugation of the aac(6')-aph(2") gene, associated with other resistance genes, was demonstrated in seven of the high-level gentamicin-resistant E. faecalis strains.
Klibi
N
N
Laboratoire MBA, Département de Biologie, Faculté de Sciences de Tunis, Campus Universitaire, 2092 Tunis, Tunisia.
Ben Slama
K
K
Masmoudi
A
A
Gharbi
S
S
Ruiz-Larrea
F
F
Fendri
C
C
Boudabous
A
A
Torres
C
C
D000123:Acetyltransferases / Q000235:genetics*; D003227:Conjugation, Genetic; D004251:DNA Transposable Elements / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D013293:Enterococcus faecalis / Q000235:genetics*; D016984:Enterococcus faecium / Q000235:genetics*; D005839:Gentamicins / Q000494:pharmacology; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy / Q000382:microbiology; D006801:Humans; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics*; D014416:Tunisia
D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D005839:Gentamicins; C108453:6'-aminoglycoside acetyltransferase-2''-aminoglycoside phosphotransferase; D000123:Acetyltransferases; D017853:Phosphotransferases (Alcohol Group Acceptor)