Bacillus cereus 569/H β-lactamase I: Structure-function relationship

Bacillus Cereus 5691h ~-lactamase I: Structure-function Relationship

Various functional groups of I~-lactamase I were modified using appropriate group specific reagents. Modification of five of the ten arginine residues and approximately fifteen of twenty-one lysine residues present in the protein could readily be achieved by reaction with diacetyl trimer and trinitrobenzene sulfonic acid respectively, without any adverse effect on catalytic activity. Reaction w...

beta-lactamase I from Bacillus cereus. Structure and site-directed mutagenesis.

The sequence of the gene for beta-lactamase I from Bacillus cereus 569/H has been redetermined. Oligonucleotide-directed mutagenesis has been carried out, and the effects of the changes on the ampicillin-resistance of Escherichia coli TG1 expressing the mutant genes have been studied. Lysine-73, close to the active-site serine-70 and a highly-conserved residue, has been converted into arginine....

Processing of Bacillus cereus 569/H beta-lactamase I in Escherichia coli and Bacillus subtilis.

The gene for Bacillus cereus 569/H beta-lactamase I, penPC, has recently been cloned and sequenced (Mézes, P. S. F., Yang, Y. Q., Hussain, M., and Lampen, J. O. (1983) FEBS Lett. 161, 195-200). A typical prokaryotic signal peptide but with no lipoprotein modification site, as present in the Bacillus licheniformis 749/C beta-lactamase, was indicated by the DNA sequence for this secretory protein...

The mechanism of catalysis and the inhibition of the Bacillus cereus zinc-dependent β-lactamase

The plot of k cat }K m against pH for the Bacillus cereus 569}H β-lactamase class B catalysed hydrolysis of benzylpenicillin and cephalosporin indicates that there are three catalytically important groups, two of pK a 5±630±2 and one of pK a 9±530±2. Below pH 5 there is an inverse second-order dependence of reactivity upon hydrogen ion concentration, indicative of the requirement of two basic r...

Bacillus cereus metallo-β-lactamase uses a branched mechanism to hydrolyze different antibiotics