Identification of a Progenitor of the CTX-M-9 Group of Extended-Spectrum β-Lactamases from Kluyvera georgiana Isolated in Guyana

ABSTRACT

Chromosomal β-lactamase genes (bla_KLUY) from six Kluyvera georgiana strains isolated in Guyana were cloned and expressed in Escherichia coli. KLUY-1 exhibited 100% amino acid identity with the extended-spectrum β-lactamase CTX-M-14. We also show that a 2.7-kb Kluyvera chromosomal region exhibits 99% nucleotide identity to a portion of In60 that includes bla_CTX-M-9.