TY - JOUR
T1 - Heterogeneity in ampr-ampc gene interaction in enterobacter cloacae
AU - Goering, Richard V.
AU - Sanders, Christine C.
AU - Sanders, W. Eugene
AU - Guay, Roger
AU - Guerin, Sylvain
N1 - Funding Information:
This work was supported in part by a grant from the Health Future Foundation, Omaha, Nebraska.
PY - 1988/7
Y1 - 1988/7
N2 - The ampR gene and its regulation of AmpC B-lactamase synthesis were investigated for Enterobacter cloacae 1194E, a wild-type strain producing a group A (pI 8.7) enzyme. Expression of the cloned E. cloacae 1194E ampR-ampC region was examined initially in Escherichia coli HBIOI. However, transformants showed only constitutive B-Iactamase expression. For study of enzyme expression in a more closely related host, the cloned E. cloacae 1194EampR-ampC region was transformed into E. cloacae 55, a wild-type strain producing a group B (pI 7.8) enzyme. Results indicated a functional E. cloacae 1194EampR gene that could not be transcomplemented by E. cloacae 55. A comparative analysis of ampR nucleotide and amino acid-sequence data from E. cloacae 1194E and E. cloacaeMHNI revealed related but divergent genes. Thermal induction studies of AmpC B-lactamase also indicated a difference between E. cloacae 1194E and E. cloacae 55 in ampR-ampC interaction. Thus, it appears that, in at least some strains of Enterobacter, significant intraspecies divergence of ampR has occurred. This heterogeneity in ampR would not have been detected with β-Iactamase expression studies conducted exclusively in E. coli.
AB - The ampR gene and its regulation of AmpC B-lactamase synthesis were investigated for Enterobacter cloacae 1194E, a wild-type strain producing a group A (pI 8.7) enzyme. Expression of the cloned E. cloacae 1194E ampR-ampC region was examined initially in Escherichia coli HBIOI. However, transformants showed only constitutive B-Iactamase expression. For study of enzyme expression in a more closely related host, the cloned E. cloacae 1194EampR-ampC region was transformed into E. cloacae 55, a wild-type strain producing a group B (pI 7.8) enzyme. Results indicated a functional E. cloacae 1194EampR gene that could not be transcomplemented by E. cloacae 55. A comparative analysis of ampR nucleotide and amino acid-sequence data from E. cloacae 1194E and E. cloacaeMHNI revealed related but divergent genes. Thermal induction studies of AmpC B-lactamase also indicated a difference between E. cloacae 1194E and E. cloacae 55 in ampR-ampC interaction. Thus, it appears that, in at least some strains of Enterobacter, significant intraspecies divergence of ampR has occurred. This heterogeneity in ampR would not have been detected with β-Iactamase expression studies conducted exclusively in E. coli.
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U2 - 10.1093/clinids/10.4.786
DO - 10.1093/clinids/10.4.786
M3 - Article
C2 - 3263686
AN - SCOPUS:0024039704
VL - 10
SP - 786
EP - 792
JO - Clinical Infectious Diseases
JF - Clinical Infectious Diseases
SN - 1058-4838
IS - 4
ER -