Cloning and characterization of the endogenous cephalosporinase gene, cepA, from Bacteroides fragilis reveals a new subgroup of Ambler class A beta-lactamases.
Author
Rogers, Marc B.; Parker, Anita C.; Smith, C. Jeffrey
Abstract
Bacteroides frgiglis CS30 is a clinical isolate resistant to high concentrations of benzylpenicillin and cephaloridine but not to cephamycin or penem antibiotics. beta-Lactam resistance is mediated by a chromosomally encoded cephalosporinase produced at a high level. The gene encoding this beta-lactamase was cloned from genomic libraries constructed in Escherichia coli and then mated with B. fragilis 638 for identification of ampicillin-resistant (Apr) strains. Apr transconjugants contained a nitrocefin-reactive protein with the physical and enzymatic properties of the original CS30 isolate. The beta-lactamase gene (cepA) was localized by deletion analysis and subcloned, and its nucleotide sequence was determined. The 903-bp cepA open reading frame encoded a 300-amino-acid precursor protein (predicted molecular mass, 34,070 Da). A 13-lactamase-deficient mutant strain of B. fiugilis 638 was constructed by insertional inactivation with the cepA gene of CS30, demonstrating strict functional homology between these chromosomal beta-lactamase genes. An extensive comparison of the CepA protein sequence by alignment with other beta-lactamases revealed the strict conservation of at least four elements common to Ambler class A. A further comparison of the CepA protein sequence with protein sequences of beta-lactamases from two other Bacteroides species indicated that they constitute their own distinct subgroup of class A beta-lactamases. Originally published Antimicrobial Agents and Chemotherapy, Vol. 37, No. 11, Nov 1993
Date
1993-11
Citation:
APA:
Rogers, Marc B., & Parker, Anita C., & Smith, C. Jeffrey. (November 1993).
Cloning and characterization of the endogenous cephalosporinase gene, cepA, from Bacteroides fragilis reveals a new subgroup of Ambler class A beta-lactamases..
Antimicrobial Agents and Chemotherapy,
37(11),
2391-
2400. Retrieved from
http://hdl.handle.net/10342/3372
MLA:
Rogers, Marc B., and Parker, Anita C., and Smith, C. Jeffrey.
"Cloning and characterization of the endogenous cephalosporinase gene, cepA, from Bacteroides fragilis reveals a new subgroup of Ambler class A beta-lactamases.". Antimicrobial Agents and Chemotherapy.
37:11. (2391-2400),
November 1993.
November 30, 2023.
http://hdl.handle.net/10342/3372.
Chicago:
Rogers, Marc B. and Parker, Anita C. and Smith, C. Jeffrey,
"Cloning and characterization of the endogenous cephalosporinase gene, cepA, from Bacteroides fragilis reveals a new subgroup of Ambler class A beta-lactamases.," Antimicrobial Agents and Chemotherapy 37, no.
11 (November 1993),
http://hdl.handle.net/10342/3372 (accessed
November 30, 2023).
AMA:
Rogers, Marc B., Parker, Anita C., Smith, C. Jeffrey.
Cloning and characterization of the endogenous cephalosporinase gene, cepA, from Bacteroides fragilis reveals a new subgroup of Ambler class A beta-lactamases.. Antimicrobial Agents and Chemotherapy.
November 1993;
37(11):
2391-2400.
http://hdl.handle.net/10342/3372. Accessed
November 30, 2023.
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Publisher
East Carolina University