Identification of CTX-M-14 Extended-Spectrum β-Lactamase in Clinical Isolates of Shigella sonnei, Escherichia coli, and Klebsiella pneumoniae in Korea

CTX-M-14 β-lactamase was identified in a stool isolate of Shigella sonnei and in blood isolates of Escherichia coli (one isolate) and Klebsiella pneumoniae (two isolates) from different parts of Korea. The amino acid sequence differed by one amino acid from CTX-M-9 (Ala-231→ Val) and was identical to that of β-lactamases recently found in China and Japan.