Molecular Analysis of Metallo--Lactamase Gene blaSPM-1-Surrounding Sequences from Disseminated Pseudomonas

The spread of clonally related carbapenem-resistant Pseudomonas aeruginosa producing the metallo--lactamase SPM-1 was found in Recife, Brazil. Upstream of blaSPM-1, a novel common region (CR4) was identified, comprising an open reading frame, orf495, whose product shares significant identity with putative recombinases, such as Orf513. CR4 may be responsible for mobilization and expression of blaSPM-1. During the last decade, several acquired carbapenem-hydro-lyzing enzymes have been identified in Pseudomonas aerugi-nosa, beginning with IMP-1 and derivatives, which are wide-spread in Japan (24, 25) and China (4) and are emerging in Europe and Canada (8, 13). Then, VIM-1 and VIM-2 enzymes were characterized, first in Italy and France (11, 22), respec-tively, but these enzymes are also highly prevalent in Korea and Greece (7, 14, 29). Recently a third member of acquired Ambler class B -lactamases, SPM-1, has been identified from a P. aeruginosa isolate in Sao Paulo, Brazil (28). The aim of this study was to analyze carbapenem-resistant P