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See detailThe penicillin-binding proteins in Streptococcus faecalis ATCC 9790
Coyette, Jean; Ghuysen, Jean-Marie ULg; Fontana, Roberta

in European Journal of Biochemistry (1980), 110(2), 445-456

Streptococcus faecalis ATCC 9790 possesses seven membrane-bound penicillin-binding proteins. They have been characterized with respect to their apparent molecular weights, relative abundance, specificity ... [more ▼]

Streptococcus faecalis ATCC 9790 possesses seven membrane-bound penicillin-binding proteins. They have been characterized with respect to their apparent molecular weights, relative abundance, specificity profiles for 15 different beta-lactam antibiotics and stability under various conditions. In water and at 37 degrees C, all the native penicillin-binding proteins have half-lives longer than 20 h except protein 3b (half-life of about 600 min) and protein 4 (half-life of about 175 min). The short-lived 80 000-Mr protein 4 is spontaneously converted into a 73 000-Mr water-soluble, penicillin-binding protein 4. Similarly, the short-lived 82 000-Mr protein 3b seems to be the protein from which the 72 000-Mr water-soluble protein X spontaneously originates during incubation of the membranes. Release of both proteins 4 and X from the membrane is maximal under alkaline conditions; it is not inhibited by various protease inhibitors. After exposure to trypsin, the 43 000-Mr membrane-bound penicillin binding protein 6 (a DD-carboxypeptidase) gives to a 30 000-Mr water-soluble protein 6. Like the parent protein, protein 6 exhibits both DD-carboxypeptidase activity and penicillin-binding ability. With proteins 6 and 6, low dose levels of p-chloromercuribenzoate prevent both enzyme activity and combination with penicillin, thus strongly suggesting that a thiol group is involved in the enzyme active center. We have shown previously [Coyette et al. in Eur. J. Biochem. 88, 297--305 (1978) and 75, 231--239 (1977)] that the DD-carboxypeptidase protein 6 fragments the benzylpenicillin molecule with formation of phenylacetylglycine. Breakdown of the complex formed between [14C]benzylpenicillin and 14 000-Mr membrane-bound protein 1 is also 'enzyme-catalysed'. Most likely, however, the released product is penicilloate. With all the other penicillin-binding proteins whose molecular weights are intermediate between those of proteins 1 and 6, breakdown of the complexes formed with [14C]benzylpenicillin results from proteolysis and is not due to the release of the bound metabolite. None of the penicillin-binding proteins behaves, by itself, as a lethal target for beta-lactam antibiotic action on the living cells. [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 detailPenicillin-binding proteins. Wall peptidoglycan assembly and resistance to penicillin: facts, doubts and hopes
Ghuysen, Jean-Marie ULg; Charlier, Paulette ULg; Coyette, Jacques ULg et al

in International Journal of Antimicrobial Agents (1997), 8(1), 45-60

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 β-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 mul-timodular polypeptides, and the association into multiprotein complexes. [less ▲]

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See detailThe Penicillin-Binding Proteins: Structure and Role in Peptidoglycan Biosynthesis
Sauvage, Eric ULg; Kerff, Frédéric ULg; Terrak, Mohammed ULg et al

in FEMS Microbiology Reviews (2008), 32(2), 234-58

Penicillin-binding proteins (PBPs) have been scrutinized for over 40 years. Recent structural information on PBPs together with the ongoing long-term biochemical experimental investigations, and results ... [more ▼]

Penicillin-binding proteins (PBPs) have been scrutinized for over 40 years. Recent structural information on PBPs together with the ongoing long-term biochemical experimental investigations, and results from more recent techniques such as protein localization by green fluorescent protein-fusion immunofluorescence or double-hybrid assay, have brought our understanding of the last stages of the peptidoglycan biosynthesis to an outstanding level that allows a broad outlook on the properties of these enzymes. Details are emerging regarding the interaction between the peptidoglycan-synthesizing PBPs and the peptidoglycan, their mesh net-like product that surrounds and protects bacteria. This review focuses on the detailed structure of PBPs and their implication in peptidoglycan synthesis, maturation and recycling. An overview of the content in PBPs of some bacteria is provided with an emphasis on comparing the biochemical properties of homologous PBPs (orthologues) belonging to different bacteria. [less ▲]

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See detailThe penicillin-binding site in the exocellular DD-carboxypeptidase-transpeptidase of Actinomadura R39
Duez, Colette ULg; Joris, Bernard ULg; Frère, Jean-Marie ULg et al

in Biochemical Journal (1981), 193

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 ... [more ▼]

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. This linkage is very labile and its hydrolysis causes the release of benzylpenicilloate. In contrast, the native benzylpenicilloyl-enzyme complex is very stable (half-life 70h at 370C) and its breakdown proceeds via fragmentation of the bound benzylpenicilloyl group [Fuad, Frere, Ghuysen, Duez & Iwatsubo (1976) Biochem. J. 155, 623-6291. [less ▲]

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See detailPenicillin-recognizing enzymes
Frère, Jean-Marie ULg; Joris, Bernard ULg; Dideberg, Otto et al

in Biochemical Society Transactions (1988), 16(6), 934-938

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See detailPenicillin-sensitive DD-carboxypeptidase from Streptomyces strain R 61
Leyh-Bouille, Mélina; Coyette, Jacques; Ghuysen, Jean-Marie ULg et al

in Biochemistry (1971), 10(11), 2163-2170

The D-alanyl-D-alanine carboxypeptidase excreted by the penicillin-sensitive Streptomyces strain R 61 is an anionic protein at pH 6.5. It does not require cations for its action. By comparison with the ... [more ▼]

The D-alanyl-D-alanine carboxypeptidase excreted by the penicillin-sensitive Streptomyces strain R 61 is an anionic protein at pH 6.5. It does not require cations for its action. By comparison with the penicillin-resistant DD-carboxypeptidase from Streptomyces albus G, the penicillin-sensitive R 61 enzyme has high Km values with all the peptides which were used but the alignment of catalytic groups is more effective in promoting hydrolysis of the peptides (high Vmax values). Moreover, the substrate structures required by the two enzymes show some differences. In contrast to the albus G DD -carboxypeptidase which is either not, or very little, affected by penicillins, the R 61 enzyme is inhibited by low dose levels of penicillin G and by cephalothin [less ▲]

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See detailPenicillin-sensitive DD-carboxypeptidases from Streptomyces strains R39 and K11
Leyh-Bouille, Mélina; Nakel, Marlies; Frère, Jean-Marie ULg et al

in Biochemistry (1972), 11(7), 1290-1298

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 ... [more ▼]

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 the presence of a free amino group at the end of the L-R3 side chain, (3) the K3 and Vmax values. Enzyme K11 has Km values which are high for both good and poor substrates. The enzyme efficiency reflects itself in Vmax values which are high for good substrates and low for poor substrates. Enzyme R39 has Km values which are low for good substrates. The enzyme efficiency toward various substrates reflects itself in the Km and, to a lesser extent, in the Vmax values, (4) the effects of penicillin. Kinetically, inhibition of enzyme K11 by penicillin is competitive. On the contrary, inhibition of enzyme R39 by penicillin is noncompetitive and increasing penicillin concentrations cause disproportionate decreases in the catalytic rate. Noncompetitiveness cannot be attributed to an irreversible inactivation of the enzyme by penicillin. [less ▲]

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See detailPenicillin-sensitive enzymes in peptidoglycan biosynthesis
Frère, Jean-Marie ULg; Joris, Bernard ULg

in CRC Critical Reviews in Microbiology (1985), 11

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See detailPenicillin-Sensitive Enzymes of Peptidoglycan Metabolism
Ghuysen, Jean-Marie ULg

in Critical Reviews in Microbiology (1977)

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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 detailPenile aneurysmal bone cyst causing urethral obstruction in a dog
Saulnier-Troff, François-Guillaume; Busoni, Valeria ULg; Hamaide, Annick ULg

Poster (2008, July)

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See detailPenile Prosthesis in the Age of the Blue Pill
Andrianne, Robert ULg

in Acta Chirurgica Belgica (2010), (110), 149-152

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See detailPenile prosthesis, sexual satisfaction and representation of male erotic value
Kempeneers, Philippe ULg; Andrianne, Robert ULg; Mormont, Christian ULg

in Sexual & Relationship Therapy (2004), 19(4),

A follow-up study conducted among 39 implanted patients and 30 partners shows that subjects' satisfaction towards prosthetic-sexulaity depends on their representation of male erotic value. The less ... [more ▼]

A follow-up study conducted among 39 implanted patients and 30 partners shows that subjects' satisfaction towards prosthetic-sexulaity depends on their representation of male erotic value. The less satisfied patients are sensitive to a normative representation that associates erotic value to criteria of "sponataneity", "naturalness", "tall an non-assisted erections". Their main dissatisfaction likely derives from the insufficiency of a prosthetic solution to restore a male self-image based on such criteria. This induces a more important impact on satisfaction rates than do functional problems (e.g. difficulties in manipulating the device, unwanted deflations, uncomfortable sensations). These patients also show an attribution bias consisting in attributing erroneously the same dissatisfaction and negative attitude towards prosthetic sexuality to their partner. Therfore, in addition to surgery, a psychosexual support is necessary to modify erotic representations and to improve the communication between the partners in order to increase sexual satisfaction with prosthesis-assisted sexuality [less ▲]

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See detailPenitence, Motherhood and Passion Devotion: Contextualising Anne of Brittany's Prayer Book, Chicago, Newberry Library, MS 83
L'Estrange, Elizabeth ULg

in Brown, Cynthia (Ed.) The Cultural and Political Legacy of Anne de Bretagne: Negotiating Convention in Books and Documents (2010)

Anne of Brittany’s prayer book, conserved in the Newberry Library in Chicago, has been somewhat neglected in discussions of Anne’s manuscripts. This may be because it has been eclipsed by those other, far ... [more ▼]

Anne of Brittany’s prayer book, conserved in the Newberry Library in Chicago, has been somewhat neglected in discussions of Anne’s manuscripts. This may be because it has been eclipsed by those other, far more luxurious and illustrated manuscripts owned by Anne, such as the Grandes Heures. However, the devotional themes of this small book, which dates from Anne’s second marriage, to Louis XII, reveal many of Anne’s interests as duchess of Brittany and queen of France. In particular the inclusion of a series of indulgences, an emphasis on St Anne, St Margaret, and St Louis, and a prayer said for the successful delivery of Clothilde, suggest that the prayer book was designed to articulate Anne’s place in the history of French monarchs, as well as her need to provide an heir for both the duchy of Brittany and the kingdom of France. This article seeks to place the little-known Newberry manuscript and its unusual contents in the context of what we already know of Anne’s devotional interests and the events of her life. Whereas previous scholarship on the manuscript, by Kamerick (Manuscripta, 1995) and L’Estrange (Holy Motherhood, 2008), has focused on the indulgences and childbearing aspects respectively, this article will bring these themes together, suggesting how the manuscript functioned as a whole, articulating a series of Breton and Capetian-Valois devotional legacies that were available to Anne as duchess and queen. Particular attention will be paid to the manuscript’s three miniatures, the illumination of David that opens the manuscript and the Penitential Psalms, and the two illuminations of Christ’s Passion. [less ▲]

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See detailPENSANDO LA CIUDAD SOSTENIBLE MÁS ALLÁ DE LA DICOTOMÍA ECOLOGÍA URBANA Y MEDIOAMBIENTE URBANO: EL CASO DE LA GOBERNANZA DEL AGUA EN COCHABAMBA
Cabrera Quispe, Juan Edson ULg; Farah, Jihad ULg

Conference (2014, November 24)

In this article, we go back on two ways of taking into account the environmental dimension in urban planning and governance. We stress the difficult articulation between these two approaches – “urban ... [more ▼]

In this article, we go back on two ways of taking into account the environmental dimension in urban planning and governance. We stress the difficult articulation between these two approaches – “urban ecology” and “urban environment” – and the actual impasse the discipline of urban planning finds itself in in its quest of the sustainable city. These two approaches for acting on the city by considering the complexity of its milieu build on different representations of this milieu and different modes of action legitimation. Negating each other, they can difficultly coexist, even less articulate. Through the example of water management in Cochabamba, we stress the tensions between these approaches. We point also to the awkward and marginalized position of urban planning and challenges it must face to regain a capacity of action in contemporary fragmented cities that know complex governance landscapes and rare or endangered resources. [less ▲]

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See detailPensar e intervenir el territorio a traves de la Teoria del Actor-Red
Cabrera Quispe, Juan Edson ULg

in Athenea Digital : Revista de Pensamiento e Investigación Social (2011), 11(1), 346

The purpose of this essay is to reflect on the similarities between some theoretical positions on the concept of territory, and its articulation with the actor-network theory. The reflection focuses on ... [more ▼]

The purpose of this essay is to reflect on the similarities between some theoretical positions on the concept of territory, and its articulation with the actor-network theory. The reflection focuses on proposing a way to understand the relationships between actors inside a dynamic of territorial intervention in public policies through the guidance of ANT [less ▲]

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See detailLa pensée "cycle de vie" au cœur des démarches d'éco-conception des procédés
Léonard, Angélique ULg

Conference (2011, December 01)

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