title: Long-term dissemination of CTX-M-5-producing hypermutable Salmonella enterica serovar typhimurium sequence type 328 strains in Russia, Belarus, and Kazakhstan.
abstract: In this paper, we present evidence of long-term circulation of cefotaxime-resistant clonally related Salmonella enterica serovar Typhimurium strains over a broad geographic area. The genetic relatedness of 88 isolates collected from multiple outbreaks and sporadic cases of nosocomial salmonellosis in various parts of Russia, Belarus, and Kazakhstan from 1996 to 2009 was established by multilocus tandem-repeat analysis (MLVA) and multilocus sequence typing (MLST). The isolates belong to sequence type 328 (ST328) and produce CTX-M-5 β-lactamase, whose gene is carried by highly related non-self-conjugative but mobilizable plasmids. Resistance to nalidixic acid and low-level resistance to ciprofloxacin is present in 37 (42%) of the isolates and in all cases is determined by various single point mutations in the gyrA gene quinolone resistance-determining region (QRDR). Isolates of the described clonal group exhibit a hypermutable phenotype that probably facilitates independent acquisition of quinolone resistance mutations.
authors: Institute of Antimicrobial Chemotherapy, Smolensk State Medical Academy, Smolensk, Russian Federation barbara.kozyreva@gmail.com.
authors: Varvara K
authors: VK
authors: Kozyreva
authors: Research Institute of Physical-Chemical Medicine, Moscow, Russian Federation.
authors: Elena N
authors: EN
authors: Ilina
authors: Research Institute of Physical-Chemical Medicine, Moscow, Russian Federation.
authors: Maja V
authors: MV
authors: Malakhova
authors: Istituto Superiore di Sanità, Rome, Italy.
authors: Alessandra
authors: A
authors: Carattoli
authors: Karaganda State Medical University, Karaganda, Kazakhstan.
authors: Ilya S
authors: IS
authors: Azizov
authors: Gomel State Medical University, Gomel, Belarus.
authors: Dmitry V
authors: DV
authors: Tapalski
authors: Institute of Antimicrobial Chemotherapy, Smolensk State Medical Academy, Smolensk, Russian Federation.
authors: Roman S
authors: RS
authors: Kozlov
authors: Institute of Antimicrobial Chemotherapy, Smolensk State Medical Academy, Smolensk, Russian Federation.
authors: Mikhail V
authors: MV
authors: Edelstein
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D004196:Disease Outbreaks; D005798:Genes, Bacterial / Q000235:genetics; D006801:Humans; D007623:Kazakhstan / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D002094:Republic of Belarus / Q000453:epidemiology; D012426:Russia / Q000453:epidemiology; D012485:Salmonella typhi / Q000201:enzymology / Q000235:genetics*; D014435:Typhoid Fever / Q000453:epidemiology / Q000382:microbiology*; D018440:beta-Lactam Resistance / Q000235:genetics; D001618:beta-Lactamases / Q000235:genetics*; D047090:beta-Lactams / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D047090:beta-Lactams; C114942:beta-lactamase CTX-M-5; D001618:beta-Lactamases