beta-lactamase;
carbapenemase activity;
resistance to antibiotics;
D O I:
10.1016/j.femsle.2004.03.028
中图分类号:
Q93 [微生物学];
学科分类号:
071005 ;
100705 ;
摘要:
Two clinical isolates, an Escherichia coli and a Klebsiella pneumoniae, with decreased Susceptibility to carbapenems were studied. This phenotype was associated with production of novel GES/IBC variant beta-lactamases, designated GES-3 (from E. coli) and GES-4 (from K pneumoniae), exhibiting carbapenemase activity. Both enzymes possessed Ser at Ambler's position 170 instead of Gly found in the beta-lactamases GES-1 and IBC-1 that lack carbapenemase activity. Additionally, position 104 in GES-4 was occupied by a Lys as in IBC-1. bla(GES-3) and bla(GES-4) Occurred as gene cassettes in the variable regions of class I integrons carried by plasmids. The structure of the GES-4-encoding integron was similar to that of previously described IBC-1 integrons. The GES-3-encoding integron was. most likely. truncated at the 3' conserved segment. (C) 2004 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.