References of "Nguyen-Distèche, Martine"
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See detailThe integral membrane FtsW protein and peptidoglycan synthase PBP3 form a subcomplex in Escherichia coli
Fraipont, Claudine ULg; Alexeeva, Svetlana; Wolf, Benoît et al

in Microbiology (2011), 157

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See detailDifferential Functionalities of Amphiphilic Peptide Segments of the Cell-Septation Penicillin-Binding Protein 3 of Escherichia Coli
Marrec-Fairley, Monique; Piette, André ULg; Gallet, Xavier et al

in Molecular Microbiology (2000), 37(5), 1019-1031

The class B M1-V577 penicillin-binding protein (PBP) 3 of Escherichia coli consists of a M1-L39 membrane anchor (bearing a cytosolic tail) that is linked via a G40-S70 intervening peptide to an R71-I236 ... [more ▼]

The class B M1-V577 penicillin-binding protein (PBP) 3 of Escherichia coli consists of a M1-L39 membrane anchor (bearing a cytosolic tail) that is linked via a G40-S70 intervening peptide to an R71-I236 non-catalytic module (containing the conserved motifs 1-3) itself linked via motif 4 to a D237-V577 catalytic module (containing the conserved motifs 5-7 of the penicilloyl serine transferases superfamily). It has been proposed that during cell septation the peptidoglycan crosslinking activity of the acyl transferase module of PBP3 is regulated by the associated M1-I236 polypeptide itself in interaction with other components of the divisome. The fold adopted by the R71-V577 polypeptide of PBP3 has been modelled by reference to the corresponding R76-S634 polypeptide of the class B Streptococcus pneumoniae PBP2x. Based on these data and the results of site-directed mutagenesis of motifs 1-3 and of peptide segments of high amphiphilicity (identified from hydrophobic moment plots), the M1-I236 polypeptide of PBP3 appears to be precisely designed to work in the way proposed. The membrane anchor and the G40-S70 sequence (containing the G57-Q66 peptide segment) upstream from the non-catalytic module have the information ensuring that PBP3 undergoes proper insertion within the divisome at the cell septation site. Motif 1 and the I74-L82 overlapping peptide segment, motif 2 and the H160-G172 overlapping peptide segment, and the G188-D197 motif 3 are located at or close to the intermodule junction. They contain the information ensuring that PBP3 folds correctly and the acyl transferase catalytic centre adopts the active configuration. The E206-V217 peptide segment is exposed at the surface of the non-catalytic module. It has the information ensuring that PBP3 fulfils its cell septation activity within the fully complemented divisome. [less ▲]

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See detailRésistance bactérienne aux beta-lactamines
Charlier, Paulette ULg; Coyette, Jacques ULg; Dehareng, Dominique ULg et al

in Medecine Sciences : M/S (1998), 14(5), 544-555

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See detailThe Bimodular G57-V577 Polypeptide Chain of the Class B Penicillin-Binding Protein 3 of Escherichia Coli Catalyzes Peptide Bond Formation from Thiolesters and Does Not Catalyze Glycan Chain Polymerization from the Lipid II Intermediate
Adam, Maggy; Fraipont, Claudine ULg; Rhazi, Noureddine ULg et al

in Journal of Bacteriology (1997), 179(19), 6005-6009

Because the specificity profile of the membrane anchor-free G57-V577 penicillin-binding protein 3 (PBP3) of Escherichia coli for a large series of beta-lactam antibiotics is similar to that of the full ... [more ▼]

Because the specificity profile of the membrane anchor-free G57-V577 penicillin-binding protein 3 (PBP3) of Escherichia coli for a large series of beta-lactam antibiotics is similar to that of the full-size membrane-bound PBP, the truncated PBP is expected to adopt the native folded conformation. The truncated PBP3 functions as a thiolesterase. In aqueous media and in the presence of millimolar concentrations of a properly structured amino compound, it catalyzes the aminolysis of the thiolester until completion, suggesting that the penicillin-binding module of PBP3 is designed to catalyze transpeptidation reactions. In contrast, the truncated PBP3 is devoid of glycan polymerization activity on the E. coli lipid II intermediate, suggesting that the non-penicillin-binding module of PBP3 is not a transglycosylase. [less ▲]

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See detailDual Multimodular Class a Penicillin-Binding Proteins in Mycobacterium Leprae
Lepage, Sophie; Dubois, Philippe ULg; Ghosh, Thushar-Kanti et al

in Journal of Bacteriology (1997), 179(14), 4627-4630

The ponA gene of cosmid L222 of the Mycobacterium leprae genome library encodes a multimodular class A penicillin-binding protein (PBP), PBP1. The PBP, labelled with a polyhistidine sequence, has been ... [more ▼]

The ponA gene of cosmid L222 of the Mycobacterium leprae genome library encodes a multimodular class A penicillin-binding protein (PBP), PBP1. The PBP, labelled with a polyhistidine sequence, has been produced in Escherichia coli, extracted from the membranes with 3-[(3-cholamidopropyl)-dimethylammonio]-1-propane-sulfonate (CHAPS) and purified by Ni2(+)-nitrilotriacetic acid-agarose chromatography. In contrast to the pon1-encoded class A PBP1, PBP1 undergoes denaturation at temperatures higher than 25 degrees C, it catalyzes acyl transfer reactions on properly structured thiolesters, and it binds penicillin with high affinity. [less ▲]

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See detailThe non-penicillin-binding module of the tripartite penicillin-binding protein 3 of Escherichia Coli is required for folding and/or stability of the penicillin-binding module and the membrane-anchoring module confers cell septation activity on the folded structure
Goffin, Colette ULg; Fraipont, Claudine ULg; Ayala, Juan et al

in Journal of Bacteriology (1996), 178(18), 5402-5409

The ftsI-encoded multimodular class B penicillin-binding protein 3 (PBP3) is a key element of the cell septation machinery of Escherichia coli. Altered ftsI genes were overexpressed, and the gene products ... [more ▼]

The ftsI-encoded multimodular class B penicillin-binding protein 3 (PBP3) is a key element of the cell septation machinery of Escherichia coli. Altered ftsI genes were overexpressed, and the gene products were analyzed with respect to the level of production, stability, penicillin affinity, and cell septation activity. In contrast to the serine beta-lactamases and low-molecular-mass PBPs which are autonomous folding entities, the S-259-to-V-577 penicillin-binding module of M-1-to-V-577 PBP3 lacks the amino acid sequence information for correct folding. The missing piece of information is provided by the associated G-57-to-E-258 non-penicillin-binding module which functions as a noncleaved, pseudointramolecular chaperone. Key elements of the folding information reside within the motif 1-containing R-60-to-W-110 polypeptide segment and within G-188-to-D-197 motif 3 of the n-PB module. The intermodule interaction is discussed in the light of the known three-dimensional structure (at 3.5-A [0.35-nm] resolution) of the analogous class B PBP2x of Streptococcus pneumoniae (S. Pares, N. Mouz, Y. Petillot, R. Hakenbeck, and O. Dideberg, Nature Struct. Biol. 3:284-289, 1996). Correct folding and adoption of a stable penicillin-binding conformation are necessary but not sufficient to confer cell septation activity to PBP3 in exponentially growing cells. The in vivo activity of PBP3 also depends on the M-1-to-E-56 amino-terminal module which encompasses the cytosol, the membrane, and the periplasm and which functions as a noncleaved pseudo-signal peptide. [less ▲]

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See detailIdentification and overexpression in Escherichia coli of a Mycobacterium leprae gene, pon1, encoding a high-molecular-mass class A penicillin-binding protein, PBP1
Basu, Joyoti; Mahapatra, Sebabrata; Kundu, Manikuntala et al

in Journal of Bacteriology (1996), 178(6), 1707-1711

Cosmid B577, a member of the collection of ordered clones corresponding to the genome of Mycobacterium leprae, contains a gene, provisionally called pon1, that encodes an 821-amino-acid-residue high ... [more ▼]

Cosmid B577, a member of the collection of ordered clones corresponding to the genome of Mycobacterium leprae, contains a gene, provisionally called pon1, that encodes an 821-amino-acid-residue high-molecular-mass class A penicillin-binding protein, provisionally called PBP1. With similar amino acid sequences and modular designs, M. leprae PBP1 is related to Escherichia coli PBP1a and PBP1b, bienzymatic proteins with transglycosylase and transpeptidase activities. When produced in E. coli, His tag-labelled derivatives of M. leprae PBP1 adopt the correct membrane topology, with the bulk of the polypeptide chain on the surface of the plasma membrane. They defy attempts at solubilization with all the detergents tested except cetyltrimethylammonium bromide. The solubilized PBP1 derivatives can be purified by affinity chromatography on Ni2+-nitrilotriacetic acid agarose. They have low affinities for the usual penicillins and cephalosporins. [less ▲]

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See detailPenicillin and Beyond: Evolution, Protein Fold, Multimodular Polypeptides, and Multiprotein Complexes
Ghuysen, Jean-Marie ULg; Charlier, Paulette ULg; Coyette, Jacques et al

in Microbial Drug Resistance : Mechanism, Epidemiology, & Disease (1996), 2(2, Summer), 163-175

As the protein sequence and structure databases expand, the relationships between proteins, the notion of protein superfamily, and the driving forces of evolution are better understood. Key steps of the ... [more ▼]

As the protein sequence and structure databases expand, the relationships between proteins, the notion of protein superfamily, and the driving forces of evolution are better understood. Key steps of the synthesis of the bacterial cell wall peptidoglycan are revisited in light of these advances. The reactions through which the D-alanyl-D-alanine depeptide is formed, utilized, and hydrolyzed and the sites of action of the glycopeptide and beta-lactam antibiotics illustrate the concept according to which new enzyme functions evolve as a result of tinkering of existing proteins. This occurs by the acquisition of local structural changes, the fusion into multimodular polypeptides, and the association into multiprotein complexes. [less ▲]

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See detailStreptomyces K15 active-site serine DD-transpeptidase: specificity profile for peptide, thiol ester and ester carbonyl donors and pathways of the transfer reactions.
Grandchamps, Jacqueline; Nguyen-Distèche, Martine ULg; Damblon, Christian ULg et al

in Biochemical Journal (1995), 307(Pt 2), 335-339

The Streptomyces K15 transferase is a penicillin-binding protein presumed to be involved in bacterial wall peptidoglycan crosslinking. It catalyses cleavage of the peptide, thiol ester or ester bond of ... [more ▼]

The Streptomyces K15 transferase is a penicillin-binding protein presumed to be involved in bacterial wall peptidoglycan crosslinking. It catalyses cleavage of the peptide, thiol ester or ester bond of carbonyl donors Z-R1-CONH-CHR2-COX-CHR3-COO- (where X is NH, S or O) and transfers the electrophilic group Z-R1-CONH-CHR2-CO to amino acceptors via an acyl-enzyme intermediate. Kinetic data suggest that the amino acceptor behaves as a simple alternative nucleophile at the level of the acyl-enzyme in the case of thiol ester and ester donors, and that it binds to the enzyme.carbonyl donor Michaelis complex and influences the rate of enzyme acylation by the carbonyl donor in the case of amide donors. Depending on the nature of the scissile bond, the enzyme has different requirements for substituents at positions R1, R2 and R3. [less ▲]

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See detailSite-directed mutagenesis of penicillin-binding protein 3 of Escherichia coli: role of Val-545
Ayala, Juan; Goffin, Colette; Nguyen-Distèche, Martine ULg et al

in FEMS Microbiology Letters (1994), 121(2), 251-256

Val545 of the Escherichia coli penicillin-binding protein 3 is essential to the acyl transfer mechanism through which the active-site serine 307 is acylated by benzylpenicillin and cephalexin and to the ... [more ▼]

Val545 of the Escherichia coli penicillin-binding protein 3 is essential to the acyl transfer mechanism through which the active-site serine 307 is acylated by benzylpenicillin and cephalexin and to the mechanism through which the protein allows rapidly growing cells to divide. [less ▲]

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See detailSerine-Type D-Ala-D-Ala Peptidases and Penicillin-Binding Proteins
Granier, Benoît; Jamin, Marc; Adam, Maggy et al

in Methods in Enzymology (1994), 244

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See detailSite-directed mutagenesis of dicarboxylic acid residues of the penicillin-binding module of the Escherichia coli penicillin-binding protein 3
Goffin, Colette ULg; Ayala, J. A.; Nguyen-Distèche, Martine ULg et al

in FEMS Microbiology Letters (1993), 113(3), 247-251

The glutamic acid E396, aspartic acid D409 and glutamic acid E411 residues of the Escherichia coli penicillin-binding protein 3 were each converted into an alanine residue. As deduced from penicillin ... [more ▼]

The glutamic acid E396, aspartic acid D409 and glutamic acid E411 residues of the Escherichia coli penicillin-binding protein 3 were each converted into an alanine residue. As deduced from penicillin-binding and complementation experiments, none of these dicarboxylic acid residues is involved in the mechanism of acylation by penicillin and none of them is essential for the in vivo functioning of the PBP. The mutation E396, however, causes an increased thermolability of the protein. [less ▲]

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See detailModular Design of the Bi(multi?) functional penicillin-binding proteins
Englebert, Serge; El Kharroubi, Aboubaker; Piras, Graziella et al

in De pedro; Höltje, J. V.; Loffelhardt, W. (Eds.) Bacterial Growth & Lysis Metabolism and Structure of the Bacterial Sacculus (1993)

Proceedings of a symposium held in Mallorca, Spain in April 1992. The goal of the meeting was to assess the present state of knowledge on the structure and physiology of the bacterium murien sacculus, and ... [more ▼]

Proceedings of a symposium held in Mallorca, Spain in April 1992. The goal of the meeting was to assess the present state of knowledge on the structure and physiology of the bacterium murien sacculus, and develop new hypotheses and strategies to promote further development of the field. The contributions reflect broadly different approaches. Papers discuss structure and chemistry, biosynthesis and maturation, regulation and control of cell wall hydrolases, penicillin interactive proteins, morphogenesis and septum formation, and cell growth. Annotation c. Book News, Inc., Portland, OR (booknews.com) [less ▲]

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See detailSecretion by Overexpression and Purification of the Water-Soluble Streptomyces K15 Dd-Transpeptidase/Penicillin-Binding Protein
Palomeque-Messia, Pilar; Quittre, Valérie; Leyh-Bouille, Mélina et al

in Biochemical Journal (1992), 288(1), 87-91

Though synthesized with a cleavable signal peptide and devoid of membrane anchors, the 262-amino-acid-residue Streptomyces K15 DD-transpeptidase/penicillin-binding protein is membrane-bound ... [more ▼]

Though synthesized with a cleavable signal peptide and devoid of membrane anchors, the 262-amino-acid-residue Streptomyces K15 DD-transpeptidase/penicillin-binding protein is membrane-bound. Overexpression in Streptomyces lividans resulted in the export of an appreciable amount of the synthesized protein (4 mg/litre of culture supernatant). The water-soluble enzyme was purified close to protein homogeneity with a yield of 75%. It requires the presence of 0.5 M-NaCl to remain soluble. It is indistinguishable from the detergent-extract wild-type enzyme with respect to molecular mass, thermostability, transpeptidase activity and penicillin-binding capacity. [less ▲]

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See detailAmino Acid Sequence of the Penicillin-Binding Protein/DD-Peptidase of Streptomyces K15. Predicted Secondary Structures of the Low Mr Penicillin-Binding Proteins of Class A
Palomeque-Messia, Pilar; Englebert, Serge; Leyh-Bouille, Melina et al

in Biochemical Journal (1991), 279(Pt 1), 223-230

The low-Mr penicillin-binding protein (PBP)/DD-transpeptidase of Streptomyces K15 is synthesized in the form of a 291-amino acid-residue precursor possessing a cleavable 29-amino acid-residue signal ... [more ▼]

The low-Mr penicillin-binding protein (PBP)/DD-transpeptidase of Streptomyces K15 is synthesized in the form of a 291-amino acid-residue precursor possessing a cleavable 29-amino acid-residue signal peptide. Sequence-similarity searches and hydrophobic-cluster analysis show that the Streptomyces K15 enzyme, the Escherichia coli PBPs/DD-carboxy-peptidases 5 and 6, the Bacillus subtilis PBP/DD-carboxypeptidase 5 and the spoIIA product (a putative PBP involved in the sporulation of B. subtilis) are structurally related and form a distinct class A of low-Mr PBPs/DD-peptidases. The distribution of the hydrophobic clusters along the amino acid sequences also shows that the Streptomyces K15 PBP, and by extension the other PBPs of class A, have similarity in the polypeptide folding, with the beta-lactamases of class A, with as reference the Streptomyces albus G and Staphylococcus aureus beta-lactamases of known three-dimensional structure. This comparison allows one to predict most of the secondary structures in the PBPs and the amino acid motifs that define the enzyme active sites. [less ▲]

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See detailAcyltransferase activities of the high-molecular-mass essential penicillin-binding proteins
Adam, Maggy; Damblon, Christian ULg; Jamin, Marc et al

in Biochemical Journal (1991), 279(Part 2), 601-604

The high-molecular-mass penicillin-binding proteins (HMM-PBPs), present in the cytoplasmic membranes of all eubacteria, are involved in important physiological events such as cell elongation, septation or ... [more ▼]

The high-molecular-mass penicillin-binding proteins (HMM-PBPs), present in the cytoplasmic membranes of all eubacteria, are involved in important physiological events such as cell elongation, septation or shape determination. Up to now it has, however, been very difficult or impossible to study the catalytic properties of the HMM-PBPs in vitro. With simple substrates, we could demonstrate that several of these proteins could catalyse the hydrolysis of some thioesters or the transfer of their acyl moiety on the amino group of a suitable acceptor nucleophile. Many of the acyl-donor substrates were hippuric acid or benzoyl-D-alanine derivatives, and their spectroscopic properties enabled a direct monitoring of the enzymic reaction. In their presence, the binding of radioactive penicillin to the PBPs was also inhibited. [less ▲]

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See detailThe Streptomyces K15 DD-peptidase/penicillin-binding protein. Active site and sequence of the N-terminal region.
Leyh-Bouille, Mélina; Vanbeeumen, Jozef; Renier-Pirlot, Suzanne et al

in Biochemical Journal (1989), 260(2), 601-604

The N-terminal region of the Streptomyces K15 DD-peptidase/penicillin-binding protein shows high homology with that of other penicillin-interactive proteins or domains. The active-site serine residue of ... [more ▼]

The N-terminal region of the Streptomyces K15 DD-peptidase/penicillin-binding protein shows high homology with that of other penicillin-interactive proteins or domains. The active-site serine residue of the conserved tetrad Ser-Xaa-Xaa-Lys occurs at position 35. There is no indication for the presence of a signal peptide or an N-terminal hydrophobic sequence, suggesting that the Streptomyces K15 enzyme is probably anchored to the membrane by a C-terminal peptide segment. [less ▲]

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See detailOverexpression, solubilization and refolding of a genetically engineered derivative of the penicillin-binding protein 3 of Escherichia coli K12.
Bartholomé-De Belder, J.; Nguyen-Distèche, Martine ULg; Houba-Herin, N. et al

in Molecular Microbiology (1988), 2(4), 519-525

Replacement of the amino-terminal 40-amino-acid region of the 588-amino-acid precursor of the membrane-bound penicillin-binding protein 3 (PBP3) by the decapeptide MKGKEFQAWI was carried out by altering ... [more ▼]

Replacement of the amino-terminal 40-amino-acid region of the 588-amino-acid precursor of the membrane-bound penicillin-binding protein 3 (PBP3) by the decapeptide MKGKEFQAWI was carried out by altering the amino-coding end of the ftsI gene. Insertion of the modified gene into a runaway-replication plasmid under the control of a fused lpp promoter and lac promoter/operator, resulted in the overexpression by Escherichia coli of the modified PBP3 (designated PBP3**) in the cytoplasm. About 80% of the accumulated PBP3** underwent sequestration in the form of insoluble protein granules that were isolated by cell breakage or cell lysis. After selective removal of contaminants by an EDTA-lysozyme/DNase (deoxyribonuclease)/Nonidet extraction, treatment of the granules with guanidinium chloride followed by dialysis against buffer containing 0.5 M NaCl yielded a refolded, water-soluble PBP3**, which, upon chromatography on Superose 12, exhibited the expected 60,000 molecular mass. The refolded PBP3** bound benzylpenicillin in a 1 to 1 molar ratio, was highly sensitive to aztreonam and showed the same degree of thermostability, in terms of penicillin-binding capacity, as the parent, membrane-bound PBP3, suggesting that protein refolding occurred with formation of the correct intramolecular interactions. Two to three mg of refolded PBP3** can be obtained from 1 litre of culture of the overproducing strain. [less ▲]

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See detailThe pH dependence of the active-site serine DD-peptidase of Streptomyces R61
Varetto, Louis; Frère, Jean-Marie ULg; Nguyen-Distèche, Martine ULg et al

in European Journal of Biochemistry (1987), 162(3), 525-531

Titration of the active-site serine DD-peptidase of Streptomyces R61 shows that formation of acyl enzyme during hydrolysis of the substrate Ac2-L-Lys-D-Ala-D-Ala and enzyme inactivation by the beta-lactam ... [more ▼]

Titration of the active-site serine DD-peptidase of Streptomyces R61 shows that formation of acyl enzyme during hydrolysis of the substrate Ac2-L-Lys-D-Ala-D-Ala and enzyme inactivation by the beta-lactam compounds benzylpenicillin, N-acetylampicillin and ampicillin relies on the acidic form of an enzyme's group of pK approximately equal to 9.5. It is proposed that protonation of a lysine epsilon-amino group facilitates initial binding by charge pairing with the free carboxylate of the substrate and the beta-lactam molecules. Lowering the pH from 7 to 5 has no effect on the second-order rate constant of enzyme acylation by benzylpenicillin and N-acetylampicillin but results in a decreased rate constant of acylation by ampicillin and Ac2-L-Lys-D-Ala-D-Ala. Protonation of the side-chain amino group of ampicillin and a decreased efficacy of the initial binding of the peptide to the enzyme seem to be responsible for the observed effects. Whatever the molecule bound to the enzyme, there is no sign for the active involvement of an enzyme's histidine residue of pK 6.5-7.0 in the hydrolysis pathway. [less ▲]

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See detailEffects of thiol reagents on Streptomyces K15 DD-peptidase-catalysed reactions
Leyh-Bouille, Mélina; Nguyen-Distèche, Martine ULg; Bellefroid-Bourguignon, Catherine et al

in Biochemical Journal (1987), 241(3), 893-897

The 26,000-Mr DD-peptidase of Streptomyces K15 binds one equivalent of thiol reagents as 5,5'-dithiobis-(2-nitrobenzoate) or p-chloromercuribenzoate (pCMB). Derivatization of the DD-peptidase by pCMB ... [more ▼]

The 26,000-Mr DD-peptidase of Streptomyces K15 binds one equivalent of thiol reagents as 5,5'-dithiobis-(2-nitrobenzoate) or p-chloromercuribenzoate (pCMB). Derivatization of the DD-peptidase by pCMB decreases the efficacy of the initial binding of the ester carbonyl donor Ac2-L-Lys-D-Ala-D-lactate to the enzyme (K), the rate of enzyme acylation by the donor (K+2) and the rate of enzyme deacylation (k+3). However, the value of the k+2/k+3 ratio, and therefore the percentage of total enzyme which, at saturating concentrations of the donor, is present as acyl-enzyme at the steady state of the reaction, are not modified. The enzyme's binding sites for pCMB and benzylpenicillin are not mutually exclusive. But, when compared with the native enzyme, the pCMB-derivatized enzyme undergoes acylation by benzylpenicillin with a decreased second-order-rate constant (k+2/K) value and gives rise to a penicilloyl adduct of increased stability. Since the acyl-enzyme mechanism is not annihilated by pCMB derivatization, it is proposed that basically, and like all the other DD-peptidases/penicillin-binding proteins so far characterized, the Streptomyces K15 DD-peptidase is an active-site-serine enzyme. [less ▲]

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