High-level resistance to ceftazidime conferred by a novel enzyme, CTX-M-32, derived from CTX-M-1 through a single Asp240-Gly substitution.
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ABSTRACT:
SUBMITTER: Cartelle M
PROVIDER: S-EPMC415568 | biostudies-literature | 2004 Jun
REPOSITORIES: biostudies-literature
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High-level resistance to ceftazidime conferred by a novel enzyme, CTX-M-32, derived from CTX-M-1 through a single Asp240-Gly substitution.
Cartelle Monica M del Mar Tomas Maria M Molina Francisca F Moure Rita R Villanueva Rosa R Bou German G
Antimicrobial agents and chemotherapy 20040601 6
A clinical strain of Escherichia coli isolated from pleural liquid with high levels of resistance to cefotaxime, ceftazidime, and aztreonam harbors a novel CTX-M gene (bla(CTX-M-32)) whose amino acid sequence differs from that of CTX-M-1 by a single Asp240-Gly substitution. Moreover, by site-directed mutagenesis we demonstrated that this replacement is a key event in ceftazidime hydrolysis ...[more]
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