[An algorithm for identification of CTX-M-type beta-lactamase genes using restriction fragment length polymorphism analysis of PCR-product].
The algorithm of the identification of the bla(CTX-M) genes coding CTX-M-type beta-lactamases providing resistance to cephalosporins III-IV was developed. This algorithm provides identification of 49 genes of 96 genes presented in the GenBank database so far. Remaining 47 genes can be identified as consisting of small sub-groups composed of 2-6 genes with the exception of sub-group of the bla(CTX-M-14)-like genes composed of 13 genes. The identification of the bla(CTX-M) genes is based on two-step restriction fragment length polymorphism analysis of 544 bp PCR-product (PCR-RFLP). In the first step, determination of subtype (cluster) of the bla(CTX-M) gene occurred using the restriction nuclease Alu I: cluster 1, -2, -8, -9 or -25. Moreover, four genes can be identified just at this step: bla(CTX-M)-59, (cluster 2); bla(CTX-M-63) (cluster 8), bla(CTX-M-45) (cluster 9), and bla(CTX-M-78) (hybrid gene between cluster 2 and cluster 25). At the second step gene identification goes on inside of each cluster separately using a set of 26 restriction nucleases. As a result of the PCR-RFLP-analysis, 23 bla(CTX-M) genes can be identified at the cluster 1, 11 genes--at the cluster 2, 4 genes--at the cluster 8, 9 genes--at the cluster 9, 1 gene--at the cluster 25, and 2 hybrid genes: bla(CTX-M-78) (between clusters 2 and 25), and bla(CTX-M-64) (between clusters 1 and 9). The described algorithm was used for identification of the blac(CTX-M) genes (n = 585) detected in Enterobacteriaceae nosocomial isolates (n = 877), collected from Russial hospitals in 2003-2007. It was shown that major genes belonged to cluster 1 (n = 543), namely--bla(CTX-M-15) gene (n = 515), bla(CTX-M-3) (n = 25), bla(CTX-M-22) (n = 1), bla(CTX-M-23) (n = 1), and bla(CTM-34) (n = 1). Moreover, the genes atributed to cluster 2 were identified: bla(CTX-M-2) (n = 1), and bla(CTX-M-5) (n = 4); and genes belonged to cluster 9: bla(CTX-M-9) (n = 2), and bla(CTX-M-14) (n = 35).
S D
SD
Priamchuk
N K
NK
Fursova
V A
VA
Anisimova
Iu N
IuN
Kovalev
I V
IV
Abaev
E N
EN
Kuzhel'naia
E A
EA
Svetoch
D000465:Algorithms; D054458:Amplified Fragment Length Polymorphism Analysis / Q000379:methods*; D002511:Cephalosporins / Q000494:pharmacology; D003428:Cross Infection / Q000382:microbiology; D004352:Drug Resistance, Microbial / Q000235:genetics*; D004755:Enterobacteriaceae / Q000235:genetics; D060005:Genotyping Techniques; D006801:Humans; D005810:Multigene Family; D012150:Polymorphism, Restriction Fragment Length; D012015:Reference Standards; D012604:Scorpion Venoms / Q000494:pharmacology; D001618:beta-Lactamases / Q000145:classification* / Q000235:genetics*
D002511:Cephalosporins; D012604:Scorpion Venoms; C091539:Chlorotoxin; D001618:beta-Lactamases