Biomaterial Database

Properties of cell wall-associated DD-carboxypeptidase of Enterococcus hirae (Streptococcus faecium) ATCC 9790 extracted with alkali. 1990

R Kariyama, and O Massidda, and L Daneo-Moore, and G D Shockman

Department of Microbiology and Immunology, School of Medicine, Temple University, Philadelphia, Pennsylvania 19140.

DD-Carboxypeptidase (DD-CPase) activity of Enterococcus hirae (Streptococcus faecium) ATCC 9790 was extracted from intact bacteria and from the insoluble residue (crude cell wall fraction) of mechanically disrupted bacteria by a brief treatment at pH 10.0 (10 mM glycine-NaOH) at 0 degrees C or by extraction with any of several detergents. Extractions with high salt concentrations failed to remove DD-CPase activity from the crude wall fraction. In contrast to N-acetylmuramoylhydrolase (both muramidase 2 and muramidase 1) activities, DD-CPase activity failed to bind to insoluble cell walls or peptidoglycan matrices. Thus, whereas muramidase 1 and muramidase 2 activities can be considered to be cell wall proteins, the bulk of the data are consistent with the interpretation that the DD-CPase of this species is a membrane protein that is sometimes found in the cell wall fraction, presumably because of hydrophobic interactions with other proteins and cell wall polymers. The binding of [14C]penicillin to penicillin-binding protein 6 (43 kilodaltons) was proportional to DD-CPase activity. Kinetic parameters were also consistent with the presence of only one DD-CPase (penicillin-binding protein 6) in E. hirae.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D010400	Penicillin G	A penicillin derivative commonly used in the form of its sodium or potassium salts in the treatment of a variety of infections. It is effective against most gram-positive bacteria and against gram-negative cocci. It has also been used as an experimental convulsant because of its actions on GAMMA-AMINOBUTYRIC ACID mediated synaptic transmission.	Benzylpenicillin,Benpen,Benzylpenicillin Potassium,Coliriocilina,Crystapen,Or-pen,Parcillin,Pekamin,Pengesod,Penibiot,Penicilina G Llorente,Penicillin G Jenapharm,Penicillin G Potassium,Penicillin G Sodium,Penicillin Grünenthal,Penilevel,Peniroger,Pfizerpen,Sodiopen,Sodipen,Sodium Benzylpenicillin,Sodium Penicillin,Unicilina,Ursopen,Van-Pen-G
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D011523	Protoplasts	The protoplasm and plasma membrane of plant, fungal, bacterial or archaeon cells without the CELL WALL.	Protoplast
D002267	Muramoylpentapeptide Carboxypeptidase	Enzyme which catalyzes the peptide cross-linking of nascent CELL WALL; PEPTIDOGLYCAN.	Carboxypeptidase Transpeptidase,Carboxypeptidase, Muramoylpentapeptide,Transpeptidase, 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
D002473	Cell Wall	The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.	Cell Walls,Wall, Cell,Walls, Cell
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D013291	Streptococcus	A genus of gram-positive, coccoid bacteria whose organisms occur in pairs or chains. No endospores are produced. Many species exist as commensals or parasites on man or animals with some being highly pathogenic. A few species are saprophytes and occur in the natural environment.