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 ...
Zhao, GuoHua +7 more
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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 ...
Leyh-Bouille, Mélina +6 more
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Purification and properties of the exocellular β-lactamase of a Actinomadura strain R39 [PDF]
Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology, 1982 The exocellular beta-lactamase (penicillin amido-beta-lactamhydrolase, EC 3.5.2.6) of Actinomadura R39 consists of one single polypeptide chain of molecular weight about 15 200. It exhibits a highly asymmetrical shape, has a low isoelectric point (at pH 5.0) and contains about 9.3% (w/w) of a polydeoxyribonucleotide with which it forms a rather stable ...
Duez, Colette +5 more
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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
Johnson, Kenneth +3 more
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Binding of β-lactam antibiotics to the exocellular
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 ...
Jean-Marie Frère +4 more
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Nucleotide sequence of the gene encoding the active-site serine β-lactamase fromActinomaduraR39 [PDF]
FEMS Microbiology Letters, 1989 The gene encoding the extracellular, active-site serine beta-lactamase of Actinomadura R39, previously cloned into Streptomyces lividans, has the information for the synthesis of a 304 amino acid protein, the amino terminal region of which has the characteristic features of a signal peptide.
Houba, Simone +6 more
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Kinetics of Reactions of the Actinomadura R39
Biochemistry, 2010 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 ...
Adediran, S. A. +4 more
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The penicillin-binding site in the exocellular
Biochemical Journal, 1981 Heat denaturation and Pronase degradation of the complex previously formed between benzylpenicillin and the exocellular DD-carboxypeptidase-transpeptidase of Actinomadura R39 yields a heptapeptide H-Leu-Pro-Ala-Ser-Asn-Gly-Val-OH, where the benzylpenicilloyl group is ester-linked to the serine residue.
Duez, Colette +4 more
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Comment on ``Two Time Scales and Violation of the Fluctuation-Dissipation Theorem in a Finite Dimensional Model for Structural Glasses'' [PDF]
, 1994 In cond-mat/0002074 Ricci-Tersenghi et al. find two linear regimes in the fluctuation-dissipation relation between density-density correlations and associated responses of the Frustrated Ising Lattice Gas.
Brooks R. A. +9 more
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Synthetic peptide inhibitors of transpeptidation by the exocellular DD‐carboxypeptidase‐transpeptidase from Actinomadura R39 [PDF]
FEBS Letters, 1981 The penicillin-sensitive exocellular carboxypeptidases-transpeptidases of Actinomycetes have been extensively studied as models of peptidoglycan construction and modification in relation to their mode of enzyme action and their mechanism of inhibition by fl-lactam antibiotics [ 1,2]. The enzyme from Actinomadura R39 has been purified to homogeneity [3]
Perkins, Harold R +2 more
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