Septal and lateral wall localization of PBP5, the major D,D-carboxypeptidase of Escherichia coli, requires substrate recognition and membrane attachment

in Molecular Microbiology (2010), 77(2), 300323

The distribution of PBP5, the major D,D-carboxypeptidase in Escherichia coli, was mapped by immunolabelling and by visualization of GFP fusion proteins in wild-type cells and in mutants lacking one or ... [more ▼]

The distribution of PBP5, the major D,D-carboxypeptidase in Escherichia coli, was mapped by immunolabelling and by visualization of GFP fusion proteins in wild-type cells and in mutants lacking one or more D,D-carboxypeptidases. In addition to being scattered around the lateral envelope, PBP5 was also concentrated at nascent division sites prior to visible constriction. Inhibiting PBP2 activity (which eliminates wall elongation) shifted PBP5 to midcell, whereas inhibiting PBP3 (which aborts divisome invagination) led to the creation of PBP5 rings at positions of preseptal wall formation, implying that PBP5 localizes to areas of ongoing peptidoglycan synthesis. A PBP5(S44G) active site mutant was more evenly dispersed, indicating that localization required enzyme activity and the availability of pentapeptide substrates. Both the membrane bound and soluble forms of PBP5 converted pentapeptides to tetrapeptides in vitro and in vivo, and the enzymes accepted the same range of substrates, including sacculi, Lipid II, muropeptides and artificial substrates. However, only the membrane-bound form localized to the developing septum and restored wild-type rod morphology to shape defective mutants, suggesting that the two events are related. The results indicate that PBP5 localization to sites of ongoing peptidoglycan synthesis is substrate dependent and requires membrane attachment. [less ▲]

Septicémie à Edwardsiella tarda: rapport de deux cas chez le marsouin commun (Phocoena phocoena)

Poster (2002, September 05)

Septicémie à Fusarium dans le décours d'une leucémie lymphoblastique aigue

Poster (1994)

Le septième livre du traité De aspectibus d’Alhazen, traduction latine médiévale de l’Optique d'Ibn al-Haytham

Book published by Académie royale de Belgique (2010)

Séquelles de l'Esclavage dans l'Histoire des Amériques

Conference (1999, December)

Séquelles tardives de déchirures de muscles ischio jambiers. Adaptation des programmes de rééducation

in Expériences en Rééducation Locomotrice (1992)

Sequence analysis of a 40 Kb DNA fragment from chromosome X of Saccharomyces cerevisiae.

Poster (1994)

Sequence analysis of a 55 Kb continuous DNA fragment (cosmids EKG097 and EKG107) from chromosome XI and sequencing of a DNA segment (cosmid 148) from chromosome X of Saccharomyces cerevisiae.

in Sequencing the yeast genome (1993)

Sequence Analysis of the Bovine Herpesvirus Type 1 Genes Homologous to the DNA Polymerase (Ul30), the Major DNA-Binding Protein (Ul29) and Icp18.5 Assembly Protein (Ul28) Genes of Herpes Simplex Virus

in Archives of Virology (1997), 142(1), 89-102

The nucleotide sequence of a 10.5 kb region (map position 0.332 to 0.410) of bovine herpesvirus type 1 (BHV-1) was determined. This region contained three open reading frames (ORFs) homologous to herpes ... [more ▼]

The nucleotide sequence of a 10.5 kb region (map position 0.332 to 0.410) of bovine herpesvirus type 1 (BHV-1) was determined. This region contained three open reading frames (ORFs) homologous to herpes simplex virus DNA polymerase catalytic subunit (DNApol, UL30), major DNA-binding protein (MDBP, UL29) and ICP18.5 assembly protein (ICP18.5, UL28). The BHV-1 DNApol. MDBP and ICP18.5 ORFs were 1246, 1203 and 826 amino acids long with a calculated molecular mass of 134.2 kDa, 124.4 kDa and 86.9 kDa, respectively. They showed a high homology with alphaherpesvirus homologs despite large differences in the G + C content of the UL30-UL28 segment ranging from 44.4% for varicella zoster virus to 71.5% for BHV-1. Particularly well conserved among Alphaherpesvirinae are the putative functional domains of the DNApol and MDBP proteins which are discussed. Phylogenetic analysis revealed that BHV-1 clustered in the Varicellovirus genus with the animal D-type viruses. In this group, the BHV-1 position was shown to vary according to the investigated genes. Indeed, pseudorabies virus clustered with BHV-1 in the DNApol tree but with equine herpesvirus 1 in the ICP18.5 tree. [less ▲]

Sequence and Comparative Analysis of Three Enterobacter Cloacae Ampc Beta-Lactamase Genes and Their Products

in Biochemical Journal (1988), 250(3), 753-60

The sequences of three Enterobacter cloacae ampC beta-lactamase genes have been determined. The deduced amino acid sequences are very similar: out of a total of 361 residues, only eight positions were ... [more ▼]

The sequences of three Enterobacter cloacae ampC beta-lactamase genes have been determined. The deduced amino acid sequences are very similar: out of a total of 361 residues, only eight positions were found to be variable, and several mutations yielded residues with very similar properties. The kinetic properties of two of the enzymes were not significantly different. The three enzymes also exhibited a high degree of homology (greater than 70%) with the ampC beta-lactamases of Escherichia coli K12 and Citrobacter freundii, confirming the homogeneity of class-C beta-lactamases. [less ▲]