Sequence analysis of bla <sub> CTX-M-28</sub> , an ESBL responsible for third-generation cephalosporin resistance in <i>Enterobacteriaceae</i>, for the first time in India
oleh: Kingsley Jemima, Verghese Susan
| Format: | Article |
|---|---|
| Diterbitkan: | Wolters Kluwer Medknow Publications 2008-04-01 |
Deskripsi
The most common group of ESBLs not belonging to the <i>bla</i> <sub> TEM</sub> or <i>bla</i> <sub> SHV</sub> families were termed <i>bla</i> <sub> CTX-M</sub> , to highlight their ESBLs′ greater activity against cefotaxime than against ceftazidime. The presence of nosocomial <i>bla</i> <sub> CTX-M-28</sub> -producing <i>Enterobacteriaceae</i> strains has not been reported earlier in Indian hospitals. The sequences of <i>bla</i> <sub> CTX-M-28</sub> gene from cephalosporin-resistant <i>Enterobacteriaceae</i> were analyzed. The structural gene encodes a 290 amino-acid protein, which is most related to the <i>bla</i> <sub> CTX-M</sub> β-lactamases. The conserved K-T-G was identified in the <i>bla</i> <sub> CTX-M-28</sub> protein sequence, but significantly, two point mutations (N→T) and (F→S) were identified in the Y-G-N- and S-T-F-K-conserved motifs respectively. These point mutations were seen in all the three sequenced isolates