Biomaterial Database

Cefoxitin resistance to beta-lactamase: a major factor for susceptibility of bacteroides fragilis to the antibiotic. 1977

G Darland, and J Birnbaum

Toluene-treated cell suspensions of Bacteroides fragilis were used to screen clinical isolates for the production of beta-lactamase. Approximately one-third of the isolates possessed considerable cephalosporinase activity. A significant correlation was found between beta-lactamase production and resistance to cephalosporin antibiotics. Several isolates were resistant to cefuroxime and cefamandole and produced enzymes capable of hydrolyzing these antibiotics. However, none of the 79 strains tested could hydrolyze the cephamycin derivative, cefoxitin. A large percentage (>90%) of the strains were susceptible to cefoxitin. Therefore, resistance to lactamase hydrolysis is a major factor for the effectiveness of cefoxitin against B. fragilis. Detailed studies of four isolates suggest that two different enzymes may be produced. Both are cephalosporinases but differ with regard to cellular distribution and substrate specificity. Cefoxitin is not a substrate for either enzyme, but it is an excellent competitive inhibitor (K(i) approximately 0.1 muM).

UI	MeSH Term	Description	Entries
D002440	Cefoxitin	A semisynthetic cephamycin antibiotic resistant to beta-lactamase.	Cefoxitin Sodium,MK-306,Mefoxin,Mefoxitin,Méfoxin,MK 306,MK306,Sodium, Cefoxitin
D002510	Cephalosporinase		beta-Lactamase II,Cephalexin Amidase,Cephalosporin Amido-beta-Lactam Hydrolase,Cephalosporin beta-Lactamase,Amidase, Cephalexin,Amido-beta-Lactam Hydrolase, Cephalosporin,Cephalosporin Amido beta Lactam Hydrolase,Cephalosporin beta Lactamase,Hydrolase, Cephalosporin Amido-beta-Lactam,beta Lactamase II,beta-Lactamase, Cephalosporin
D002511	Cephalosporins	A group of broad-spectrum antibiotics first isolated from the Mediterranean fungus ACREMONIUM. They contain the beta-lactam moiety thia-azabicyclo-octenecarboxylic acid also called 7-aminocephalosporanic acid.	Antibiotics, Cephalosporin,Cephalosporanic Acid,Cephalosporin,Cephalosporin Antibiotic,Cephalosporanic Acids,Acid, Cephalosporanic,Acids, Cephalosporanic,Antibiotic, Cephalosporin,Cephalosporin Antibiotics
D004352	Drug Resistance, Microbial	The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).	Antibiotic Resistance,Antibiotic Resistance, Microbial,Antimicrobial Resistance, Drug,Antimicrobial Drug Resistance,Antimicrobial Drug Resistances,Antimicrobial Resistances, Drug,Drug Antimicrobial Resistance,Drug Antimicrobial Resistances,Drug Resistances, Microbial,Resistance, Antibiotic,Resistance, Drug Antimicrobial,Resistances, Drug Antimicrobial
D000581	Amidohydrolases	Any member of the class of enzymes that catalyze the cleavage of amide bonds and result in the addition of water to the resulting molecules.	Amidases,Amidohydrolase
D001441	Bacteroides fragilis	Gram-negative bacteria occurring in the lower intestinal tracts of man and other animals. It is the most common species of anaerobic bacteria isolated from human soft tissue infections.
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships