Crystal Structure of the Actinomadura R39 DD-peptidase Reveals New Domains in Penicillin-binding Proteins* [PDF]
Journal of Biological Chemistry, 2005 Actinomadura sp. R39 produces an exocellular DD-peptidase/penicillin-binding protein (PBP) whose primary structure is similar to that of Escherichia coli PBP4.
E. Sauvage +6 more
semanticscholar +4 more sources
Kinetics of reactions of the Actinomadura R39 DD-peptidase with specific substrates. [PDF]
Biochemistry, 2011 The Actinomadura R39 DD-peptidase catalyzes the hydrolysis and aminolysis of a number of small peptides and depsipeptides. Details of its substrate specificity and the nature of its in vivo substrate are not, however, well understood. This paper describes the interactions of the R39 enzyme with two peptidoglycan-mimetic substrates 3-(D-cysteinyl ...
S. Adediran +4 more
semanticscholar +5 more sources
Penicillin-sensitive DD-carboxypeptidases from Streptomyces strains R39 and K11. [PDF]
Biochemistry, 1972 The two penicillin-sensitive DD-carboxypeptidases from Streptomyces R39 and K11 are anionic at pH 8. They specifically recognize a C-terminal L-R3-D-alanyl-D sequence with a long side chain at the R3 position. The two enzymes differ from each other with respect to: (1) the effects of ionic strength on activity, (2) the influence exerted on activity by ...
M. Leyh-Bouille +6 more
semanticscholar +3 more sources
Site-directed mutagenesis of the Actinomadura R39 DD-peptidase. [PDF]
Biochemical Journal, 1997 The role of various residues in the conserved structural elements of the Actinomadura R39 penicillin-sensitive DD-peptidase has been studied by site-directed mutagenesis. Replacement of Ser-298 of the ‘SDN loop’ by Ala or Gly significantly decreased the kcat/Km value for the peptide substrate, but only by a factor of 15 and had little effect on the ...
G. Zhao +7 more
semanticscholar +4 more sources
Inhibition of DD-peptidases by a specific trifluoroketone: crystal structure of a complex with the Actinomadura R39 DD-peptidase. [PDF]
Biochemistry, 2013 Inhibitors of bacterial DD-peptidases represent potential antibiotics. In the search for alternatives to β-lactams, we have investigated a series of compounds designed to generate transition state analogue structures upon reaction with DD-peptidases. The compounds contain a combination of a peptidoglycan-mimetic specificity handle and a warhead capable
Liudmila Dzhekieva +7 more
semanticscholar +4 more sources
Inhibition of Streptococcus pneumoniae Penicillin-Binding Protein 2x and Actinomadura R39 DD-Peptidase Activities by Ceftaroline [PDF]
Antimicrobial Agents and Chemotherapy, 2012 ABSTRACT Although the rate of acylation of a penicillin-resistant form of Streptococcus pneumoniae penicillin-binding protein 2x (PBP2x) by ceftaroline is 80-fold lower than that of its penicillin-sensitive counterpart, it remains sufficiently high ( k 2
A. Zervosen, A. Zapun, J. Frère
semanticscholar +4 more sources
Binding of beta-lactam antibiotics to the exocellular DD-carboxypeptidase-transpeptidase of Streptomyces R39. [PDF]
Biochemical Journal, 1974 Benzylpenicillin and cephaloridine reacted with the exocellular dd-carboxypeptidase–transpeptidase from Streptomyces R39 to form equimolar and inactive antibiotic–enzyme complexes. At saturation, the molar ratio of chromogenic cephalosporin 87-312 to enzyme was 1.3:1, but this discrepancy might be due to a lack of accuracy in the measurement of the ...
J. Frère +3 more
semanticscholar +3 more sources
Interaction of clavulanate with the beta-lactamases of Streptomyces albus G and Actinomadura R39. [PDF]
Biochemical Journal, 1982 The reactions of beta-lactamases of Actinomadura R39 and Streptomyces albus G with clavulanate proceed along branched pathways. Both enzymes perform the hydrolysis of this beta-lactam with rather high efficiencies (kcat. = 18s-1 and 52s-1 respectively). If large clavulanate/enzyme ratios are used, complete inactivation of the enzymes is observed.
J. Frère +3 more
semanticscholar +3 more sources
Exocellular β-Lactamases of Streptomyces albus G and Strains R39 and K11 [PDF]
Antimicrobial Agents and Chemotherapy, 1973 The β-lactamases excreted by the highly benzylpenicillin-susceptible Streptomyces strain R39 and the highly benzylpenicillin-resistant Streptomyces albus G were isolated and purified. Neither β-lactamase exhibited dd -carboxypeptidase activity. Both were anionic at
Kenneth A. Johnson +3 more
semanticscholar +4 more sources
Mode of interaction between β-lactam antibiotics and the exocellular DD-carboxypeptidase--transpeptidase from Streptomyces R39 [PDF]
Biochemical Journal, 1976 The exocellular DD-carboxypeptidase-transpeptidase of Streptomyces R39 is inhibited by beta-lactam antibiotics according to the same general scheme of reaction as the exocellular DD-carboxypeptidase-transpeptidase of Streptomyces R61. However, the values for the kinetic constants involved in the reaction are very different for the two enzymes and ...
N. Fuad +4 more
semanticscholar +3 more sources