Topology; C terminal-Sequence; Homology; Isoelectrical focusing; Proteins; Enzyme; Binding protein; Antibiotic; Active site; Binding site; Molecular structure; Chromatography; Microorganism culture; Gel electrophoresis; Radiolabelling; Biomembrane; Topologie; Séquence C terminale; Homologie; Focalisation isoélectrique; Culture microorganisme; Chromatographie; Membrane biologique; Marquage radioisotopique; Electrophorèse gel; Structure moléculaire; Site fixation; Site actif; Antibiotique; Protéine de liaison; Protéine; Topología; Membrana biológica; Marcación radioisotópica; Electroforesis gel; Cultivo microorganismo; Cromatografía; Estructura molecular; Sitio fijación; Lugar activo; Antibiótico; Proteina de enlace; Enzima; Proteina; Focalización isoeléctrica; Homología; Secuencia C terminal
Abstract :
[en] The membrane-bound 43,000-Mr penicillin-binding protein no. 6 (PBP6) of Enterococcus hirae consists of a 30,000-Mr DD-peptidase/penicillin-binding domain and a approximately 130-residue C-terminal appendage. Removal of this appendage by trypsin proteolysis has no marked effect on the catalytic activity and penicillin-binding capacity of the PBP. Anchorage of the PBP in the membrane appears to be mediated by a short 15-20-residue stretch at the C-terminal end of the appendage. The sequence of the 50-residue N-terminal region of the PBP shows high degree of homology with the sequences of the corresponding regions of the PBPs5 of Escherichia coli and Bacillus subtilis. On this basis the active-site serine residue occurs at position 35 in the enterococcal PBP.