Extended-spectrum beta-lactamases in Shigella flexneri from Argentina: first report of TOHO-1 outside Japan.
A 9-year nation-wide survey of the presence of extended-spectrum beta-lactamases (ESBLs) in Shigella flexneri is described. Ten of 9033 (0.1%) isolates produced ESBLs, which were characterized by isoelectric focusing, PCR and DNA sequencing. These were CTX-M-2 (five isolates), TOHO-1 (one isolate), SHV-2 (two isolates) and PER-2 (two isolates, the first report in S. flexneri world wide). The emergence of each ESBL type in S. flexneri was not restricted to a particular region of Argentina. TOHO-1 showed a more basic isoelectric point (8.4) than that previously found (7.8) and its encoding gene (bla(TOHO-1a)) harboured a silent change, G825A, relative to the reported bla(TOHO-1). All the ESBL-encoding genes were transferred to Escherichia coli by conjugation. PFGE analysis indicated that the 10 ESBL-producing S. flexneri isolates were subtypes of a unique clone.
Andres
Patricia
P
Servicio Antimicrobianos, Departamento Bacteriología, INEI-ANLIS Dr. Carlos G. Malbrán, Av. Vélez Sarsfield 563 (1281), Buenos Aires, Argentina.
Petroni
Alejandro
A
Faccone
Diego
D
Pasterán
Fernando
F
Melano
Roberto
R
Rapoport
Melina
M
Martínez
Mariela
M
Culasso
Catalina
C
Di Bella
Adriana
A
Irigoyen
Bettina
B
Mulki
Jorgelina
J
Procopio
Adriana
A
von Specht
Martha
M
Galas
Marcelo
M
D019943:Amino Acid Substitution; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001118:Argentina; D015373:Bacterial Typing Techniques; D003227:Conjugation, Genetic; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004405:Dysentery, Bacillary / Q000382:microbiology; D016521:Electrophoresis, Gel, Pulsed-Field; D022761:Gene Transfer, Horizontal; D006801:Humans; D007525:Isoelectric Focusing; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012763:Shigella flexneri / Q000187:drug effects* / Q000201:enzymology* / Q000302:isolation & purification; D001618:beta-Lactamases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D047090:beta-Lactams / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D047090:beta-Lactams; C062760:beta-lactamase SHV-2; D001618:beta-Lactamases