Biomaterial Database

DD-Carboxypeptidase activity of membrane fragments of Mycobacterium smegmatis. Enzymatic properties and sensitivity to beta-lactam antibiotics. 1978

H M Eun, and A Yapo, and J F Petit

A DD-carboxypeptidase activity is present in membrane fragments of Mycobacterium smegmatis. Kinetic parameters of the enzymatic activity have been studied using UDP-N-glycolylmuramyl-L-alanyl-gamma-D-glutamyl-meso-2,2'-diaminopimelyl-D-[14C]alanyl-D-[14C]alanine as substrate. The DD-carboxypeptidase can be solubilized by Triton X-100 and Genapol X-100. It is inhibited by beta-lactam antibiotics although intact cells of M. smegmatis are insensitive to that kind of antibiotics. Inhibition by penicillin G is slowly reversible. By storage, at -20degrees C, kinetic parameters and sensitivity to penicillin G vary non-concomittantly, suggesting a penicillin binding site different from the substrate binding site.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009161	Mycobacterium	A genus of gram-positive, aerobic bacteria. Most species are free-living in soil and water, but the major habitat for some is the diseased tissue of warm-blooded hosts.	Mycobacteria
D010406	Penicillins	A group of antibiotics that contain 6-aminopenicillanic acid with a side chain attached to the 6-amino group. The penicillin nucleus is the chief structural requirement for biological activity. The side-chain structure determines many of the antibacterial and pharmacological characteristics. (Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1065)	Antibiotics, Penicillin,Penicillin,Penicillin Antibiotics
D002267	Muramoylpentapeptide Carboxypeptidase	Enzyme which catalyzes the peptide cross-linking of nascent CELL WALL; PEPTIDOGLYCAN.	Carboxypeptidase Transpeptidase,Carboxypeptidase, Muramoylpentapeptide,Transpeptidase, Carboxypeptidase
D002268	Carboxypeptidases	Enzymes that act at a free C-terminus of a polypeptide to liberate a single amino acid residue.	Carboxypeptidase
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
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