References of "Leyh-Bouille, Mélina"
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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 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 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 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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See detailStreptomyces K15 DD-peptidase-catalysed reactions with suicide β-lactam carbonyl donors
Leyh-Bouille, Mélina; Nguyen-Distèche, Martine ULg; Pirlot, Suzanne et al

in Biochemical Journal (1986), 235(1), 177-182

The values of the kinetic parameters that govern the interactions between the Streptomyces K15 DD-peptidase and beta-lactam compounds were determined by measuring the inactivating effect that these ... [more ▼]

The values of the kinetic parameters that govern the interactions between the Streptomyces K15 DD-peptidase and beta-lactam compounds were determined by measuring the inactivating effect that these compounds exert on the transpeptidase activity of the enzyme and, in the case of [14C]benzylpenicillin and [14C]cefoxitin, by measuring the amounts of acyl-enzyme formed during the reaction. K15 DD-peptidase binds benzylpenicillin or cefoxitin at a molar ratio of 1:1. Benzylpenicilloate is the major product released during breakdown of the acyl-enzyme formed with benzylpenicillin. Benzylpenicillin is not a better acylating agent than the amide Ac2-L-Lys-D-Ala-D-Ala and ester Ac2-L-Lys-D-Ala-D-lactatecarbonyl-donor substrates. beta-Lactam compounds possessing a methoxy group on the alpha-face of the molecule show high inactivating potency. [less ▲]

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See detailActive-site-serine D-alanyl-D-alanine-cleaving-peptidase-catalysed acyl-transfer reactions. Procedures for studying the penicillin-binding proteins of bacterial plasma membranes
Ghuysen, Jean-Marie ULg; Frère, Jean-Marie ULg; Leyh-Bouille, Mélina et al

in Biochemical Journal (1986), 235(1), 159-165

Under certain conditions, the values of the parameters that govern the interactions between the active-site-serine D-alanyl-D-alanine-cleaving peptidases and both carbonyl-donor substrates and beta-lactam ... [more ▼]

Under certain conditions, the values of the parameters that govern the interactions between the active-site-serine D-alanyl-D-alanine-cleaving peptidases and both carbonyl-donor substrates and beta-lactam suicide substrates can be determined on the basis of the amounts of (serine ester-linked) acyl-protein formed during the reactions. Expressing the 'affinity' of a beta-lactam compound for a DD-peptidase in terms of second-order rate constant of enzyme acylation and first-order rate constant of acyl-enzyme breakdown rests upon specific features of the interaction (at a given temperature) and permits study of structure-activity relationships, analysis of the mechanism of intrinsic resistance and use of a 'specificity index' to define the capacity of a beta-lactam compound of discriminating between various sensitive enzymes. From knowledge of the first-order rate constant of acyl-enzyme breakdown and the given time of incubation, the beta-lactam compound concentrations that are necessary to achieve given extents of DD-peptidase inactivation can be converted into the second-order rate constant of enzyme acylation. The principles thus developed can be applied to the study of the multiple penicillin-binding proteins that occur in the plasma membranes of bacteria. [less ▲]

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See detailStreptomyces K15 DD-peptidase-catalysed reactions with ester and amide carbonyl donors
Nguyen-Distèche, Martine ULg; Leyh-Bouille, Mélina; Pirlot, Suzanne et al

in Biochemical Journal (1986), 235(1), 167-176

In water, the purified 26 000-Mr membrane-bound DD-peptidase of Streptomyces K15 hydrolyses the ester carbonyl donor Ac2-L-Lys-D-Ala-D-lactate (release of D-lactate) and the amide carbonyl donor Ac2-L-Lys ... [more ▼]

In water, the purified 26 000-Mr membrane-bound DD-peptidase of Streptomyces K15 hydrolyses the ester carbonyl donor Ac2-L-Lys-D-Ala-D-lactate (release of D-lactate) and the amide carbonyl donor Ac2-L-Lys-D-Ala-D-Ala (release of D-alanine) with accumulation of acyl- (Ac2-L-Lys-D-alanyl-)enzyme. Whereas hydrolysis of the ester substrate proceeds to completion, hydrolysis of the amide substrate is negligible because of the capacity of the K15 DD-peptidase for utilizing the released D-alanine in a transfer reaction (Ac2-L-Lys-D-Ala-D-Ala + D-Ala----Ac2-L-Lys-D-Ala-D-Ala + D-Ala) that maintains the concentration of the amide substrate at a constant level. In the presence of an amino acceptor X-NH2 (Gly-Gly or Gly-L-Ala) related to the Streptomyces peptidoglycan, both amide and ester carbonyl donors are processed without detectable accumulation of acyl-enzyme. Under proper conditions, the acceptor activity of water and, in the case of the amide substrate, the acceptor activity of the released D-alanine can be totally overcome so that the two substrates are quantitatively converted into transpeptidated product Ac2-L-Lys-D-Ala-NH-X (and hydrolysis is prevented). Experimental evidence suggests that the amino acceptor modifies both the binding of the carbonyl donor to the enzyme and the ensuing rate of enzyme acylation. [less ▲]

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See detailBacterial wall peptidoglycan, DD-peptidases and beta-lactam antibiotics
Ghuysen, Jean-Marie ULg; Frère, Jean-Marie ULg; Leyh-Bouille, Mélina et al

in Scandinavian Journal of Infectious Diseases (1984), 42

Wall peptidoglycan expansion in bacteria rests upon a cytoplasmic D-Ala: D-Ala ligase (ADP) which catalyses synthesis of a D-Ala-D-Ala dipeptide (with accompanying hydrolysis of one molecule of ATP) and a ... [more ▼]

Wall peptidoglycan expansion in bacteria rests upon a cytoplasmic D-Ala: D-Ala ligase (ADP) which catalyses synthesis of a D-Ala-D-Ala dipeptide (with accompanying hydrolysis of one molecule of ATP) and a set of DD-peptidases which utilize this D-Ala-D-Ala dipeptide--once it has been translocated at the outer face of the plasma membrane as the C-terminal portion of a disaccharide peptide unit--as carbonyl donor for transpeptidation and carboxypeptidation reactions (without additional energy expenditure). Four DD-peptidases have been selected which differ from each other with respect to the effects that amino compounds exert on the fate and rate of consumption of a D-Ala-D-Ala terminated amide carbonyl donor analogue. They serve as models to understand the different mechanisms by which the DD-peptidases perform catalysis and show widely varying responses to the action of beta-lactams, from extreme sensitivity to very high resistance. [less ▲]

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See detailInstrinct Resistance to beta-lactam antibiotics at the level of the enzyme sites. Many challenges, some achievements
Ghuysen, Jean-Marie ULg; Charlier, P.; Coyette, Jean et al

in Wiedemann, B.; Guysen, Jean-Marie; Spitzy, K. H. (Eds.) et al Symposium Mechanisms of resistance to beta-lactam antibiotics : Proceedings (1983)

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See detailThe active sites of the D-alanyl-D-alanine-cleaving peptidases
Charlier, Paulette ULg; Dideberg, Otto; Dive, Georges ULg et al

in Hakenbeck, Regine; Höltje, Joachim-Volker; Labischinski, Harald (Eds.) The Target Penicillin : the Murein Sacculus of Bacterial Cell Walls Architecture and Growth : Proceedings (1983)

The active site structures of D-alanyl-D-alanine-cleaving peptidases G, R61, R39, and K15 from Streptomyces and Actinomadura are discussed in relation to their substrate specificities and kinetic ... [more ▼]

The active site structures of D-alanyl-D-alanine-cleaving peptidases G, R61, R39, and K15 from Streptomyces and Actinomadura are discussed in relation to their substrate specificities and kinetic mechanisms. [less ▲]

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See detailIsolation of the membrane-bound 26 000-Mr penicillin-binding protein of Streptomyces strain K15 in the form of a penicillin-sensitive D-alanyl-D-alanine-cleaving transpeptidase
Nguyen-Distèche, Martine ULg; Leyh-Bouille, Mélina; Ghuysen, Jean-Marie ULg

in Biochemical Journal (1982), 207(1), 109-115

The membrane-bound, 26 000-Mr penicillin-binding protein of Streptomyces K15 has been isolated in the form of an effective, penicillin-sensitive D-alanyl-D-alanine-cleaving peptidase exhibiting high ... [more ▼]

The membrane-bound, 26 000-Mr penicillin-binding protein of Streptomyces K15 has been isolated in the form of an effective, penicillin-sensitive D-alanyl-D-alanine-cleaving peptidase exhibiting high transpeptidase activity (greater than 95%) and very low carboxy-peptidase activity (less than 5%). The penicillin-binding protein/transpeptidase can be extracted directly from the mycelium with N-cetyl-NNN-trimethylammonium bromide (Cetavlon) and subsequently obtained at 90% purity and with an 8000-fold specific enrichment (when compared with the activity of the isolated membranes) by a two-step procedure involving Sephadex filtration and affinity chromatography on ampicillin-linked CH Sepharose 4B in the presence of detergent. At saturating concentrations of the co-substrates diacetyl-L-Lys-D-Ala-D-Ala and Gly-Gly, the catalytic-centre activity is about 0.3 s-1. [less ▲]

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See detailOn the DD-carboxypeptidase enzyme system of Streptomyces strain K15
Leyh-Bouille, Mélina; Nguyen-Distèche, Martine ULg; Ghuysen, Jean-Marie ULg

in European Journal of Biochemistry (1981), 115(3), 579-584

Streptomyces K15 possesses a set of exocellular and cell-bound D-alanyl-D-alanine carboxypeptidases. Four of them have been isolated to the stage where each enzyme preparation contains on single ... [more ▼]

Streptomyces K15 possesses a set of exocellular and cell-bound D-alanyl-D-alanine carboxypeptidases. Four of them have been isolated to the stage where each enzyme preparation contains on single penicillin-binding protein. The exocellular 54000-Mr enzyme is extremely sensitive to benzylpenicillin and performs low transpeptidase activity on the carbonyl-donor/amino-acceptor tetrapeptide ACLLys(Gly)-DAla-DAla. The exocellular 40 000-Mr enzyme and the two lysozyme-releasable 40 000-Mr and 38 000-Mr enzymes are moderately sensitive to benzylpenicillin and have a high propensity to catalyse dimer formation from the aforementioned tetrapeptide monomer. [less ▲]

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See detailPrimary structure of the wall peptidoglycan of leprosy-derived corynebacteria
Janczura, E.; Leyh-Bouille, Mélina; Cocito, C. et al

in Journal of Bacteriology (1981), 145(2), 775-779

The cell walls isolated from axenically grown leprosy-derived corynebacteria were submitted to various chemical and enzymatic degradations. The glycan strands of the wall peptidoglycan are essentially ... [more ▼]

The cell walls isolated from axenically grown leprosy-derived corynebacteria were submitted to various chemical and enzymatic degradations. The glycan strands of the wall peptidoglycan are essentially composed of N-acetylglycosaminyl-N-acetylmuramic acid disaccharide units. Small amounts of N-acetylglycosaminyl-N-glycolylmuramic acid (less than 10%) were also detected. The muramic acid residues of adjacent glycan strands are substituted by amidated tetrapeptide units which, in turn, are cross-linked through direct linkages extending between the C-terminal D-alanine residue of one tetrapeptide and the mesodiaminopimelic acid residue of another tetrapeptide. Such a structure is very similar to that of the wall peptidoglycan found in the taxonomically related microorganisms of the Corynebacterium, Mycobacterium, and Nocardia groups. [less ▲]

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See detailPenicillins and Δ3-cephalosporins as inhibitors and mechanism-based inactivators of D-alanyl-D-Ala peptidases
Ghuysen, Jean-Marie ULg; Frère, Jean-Marie ULg; Leyh-Bouille, Mélina et al

in Burgen, A. S. V.; Roberts, G. C. K. (Eds.) Topics in molecular pharmacology (1981)

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See detailThe active centres in penicillin-sensitive enzymes
Ghuysen, Jean-Marie ULg; Frère, Jean-Marie ULg; Leyh-Bouille, Mélina et al

in Philosophical Transactions : Biological Sciences (1980), 289(1036), 285-301

The interaction between beta-lactam antibiotics and the penicillin-sensitive enzymes is a multiple-step process. Binding of the beta-lactam ring of the penam (or 3-cepham) nucleus occurs at binding site ... [more ▼]

The interaction between beta-lactam antibiotics and the penicillin-sensitive enzymes is a multiple-step process. Binding of the beta-lactam ring of the penam (or 3-cepham) nucleus occurs at binding site no. 1. Interaction between the N-14 substituent of the bound molecule and binding site no. 2 induces changes in binding site no. 1. In turn, the catalytic site thus created increases the chemical reactivity of the beta-lactam amide bond. As the beta-lactam ring opens and acylates an enzyme serine residue, the interaction between the thiazolidine (or dihydrothiazine) ring and binding site no. 3 stabilizes the acyl-enzyme complex. Enzyme regeneration slowly proceeds either by direct elimination of the penicilloyl moiety or via C-5-C-6 splitting of the bound metabolite. The fragment arising from thiazolidine yields free N-formyl-D-penicillamine while the enzyme-linked N-acylglycyl fragment is immediately attacked by an exogenous nucleophile correctly positioned on the acceptor site. Similarly, the enzyme action on L-X-D-Ala-D-Ala terminated peptides is mediated via a binding site no. 1 that combines with D-Ala-D-Ala, a binding site no. 2 that interacts with the side chain of the preceding L-residue, an inducible catalytic site and an acceptor site. Enzymes are known that form a transitory L-X-D-Ala-enzyme complex where the acyl group is ester-linked to the same serine residue as that involved in the formation of the penicilloyl-enzyme complex (Waxman et al., this symposium). Other enzymes, however, may function as catalyst templates. Depending on the enzymes, the independence of the beta-lactam and L-X-D-Ala-D-Ala active centres is more or less pronounced. [less ▲]

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See detailPenicillin-binding proteins in the membranes of Streptomyces sp
Dusart, Jean; Leyh-Bouille, Mélina; Nguyen-Distèche, Martine ULg et al

in Archives Internationales de Physiologie et de Biochimie (1980, February 01), 88(1), 27-29

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See detailOn the Active Centers of Serine and Zn II DD-carboxyppetidases
Charlier, Paulette ULg; Coyette, Jacques ULg; Dideberg, Otto et al

in Gregory, G.I. (Ed.) Recent advances in the Chemistry of beta-lactam antibiotics (1980)

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See detailUse of model enzymes in the determination of the mode of action of penicillins and delta 3-cephalosporins
Ghuysen, Jean-Marie ULg; Frère, Jean-Marie ULg; Leyh-Bouille, Mélina et al

in Annual Review of Biochemistry (1979), 48

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See detailInteraction between penicillin and its enzyme target
Ghuysen, Jean-Marie ULg; Frère, Jean-Marie ULg; Leyh-Bouille, Mélina et al

in Microbial Drug Resistance : Mechanism, Epidemiology, & Disease (1979), 2

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