Biomaterial Database

Inactivation of Bacillus cereus beta-lactamase I by 6 beta-bromopencillanic acid: mechanism. 1980

S A Cohen, and R F Pratt

The mechanism of the inactivation of Bacillus cereus beta-lactamase I by 6 beta-bromopenicillanic acid, a probable suicide substrate [see Loosemore, M.J., Cohen, S.A., & Pratt, R.F. (1980) Biochemistry (preceding paper in this issue)], is described. Inactivation is accompanied by covalent modification of the protein with the appearance of a characteristic chromophore at 326 nm. Ultraviolet (UV) absorption, nuclear magnetic resonance (NMR), and circular dichroic (CD) spectra of the modified protein, of a modified peptide derived from the protein by enzymatic digestion, and of relevant model compounds suggest that acylation of the enzyme by 6 beta-bromopenicillanic acid is accompanied by rearrangement and cyclization of the inhibitor to a 2,3-dihydro-1,4-thiazine-3,6-dicarboxylic acid derivative, which is the observed chromophore. The acylated residue is shown to be Ser-70. The mechanism of action of beta-lactamase inhibitors is discussed.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009682	Magnetic Resonance Spectroscopy	Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).	In Vivo NMR Spectroscopy,MR Spectroscopy,Magnetic Resonance,NMR Spectroscopy,NMR Spectroscopy, In Vivo,Nuclear Magnetic Resonance,Spectroscopy, Magnetic Resonance,Spectroscopy, NMR,Spectroscopy, Nuclear Magnetic Resonance,Magnetic Resonance Spectroscopies,Magnetic Resonance, Nuclear,NMR Spectroscopies,Resonance Spectroscopy, Magnetic,Resonance, Magnetic,Resonance, Nuclear Magnetic,Spectroscopies, NMR,Spectroscopy, MR
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
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
D002942	Circular Dichroism	A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Circular Dichroism, Vibrational,Dichroism, Circular,Vibrational Circular Dichroism
D000596	Amino Acids	Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.	Amino Acid,Acid, Amino,Acids, Amino
D001409	Bacillus cereus	A species of rod-shaped bacteria that is a common soil saprophyte. Its spores are widespread and multiplication has been observed chiefly in foods. Contamination may lead to food poisoning.
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D013056	Spectrophotometry, Ultraviolet	Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Ultraviolet Spectrophotometry
D065093	beta-Lactamase Inhibitors	Endogenous substances and drugs that inhibit or block the activity of BETA-LACTAMASES.	beta Lactamase Inhibitor,beta Lactamase Inhibitors,beta-Lactamase Inhibitor,beta Lactamase Antagonists,Antagonists, beta Lactamase,Inhibitor, beta Lactamase,Inhibitor, beta-Lactamase,Inhibitors, beta Lactamase,Inhibitors, beta-Lactamase,Lactamase Antagonists, beta,Lactamase Inhibitor, beta,Lactamase Inhibitors, beta