Actin-related proteins in Actinobacillus pleuropneumoniae and their interactions with actin-binding proteins

• Published in: Microbiology (Society for General Microbiology) 1999-11, Vol.145 (11), p.3235-3244
• Main Authors: Guerrero-Barrera, A.L, Garza, M. de la, Mondragon, R, Garcia-Cuellar, C, Segura-Nieto, M
• Format: Article
• Language: English
• Subjects: actin-binding protein; Actinobacillus pleuropneumoniae; Actinobacillus pleuropneumoniae - chemistry; Amino Acids - analysis; Anabaena variabilis; animal diseases; animal health; Animals; Ap-PARP protein; bacterial infections; Bacteriology; Biological and medical sciences; Blotting, Western; Chromatography, Affinity; Cytochalasin D - metabolism; Electrophoresis, Gel, Two-Dimensional; Electrophoresis, Polyacrylamide Gel; Fundamental and applied biological sciences. Psychology; Microbiology; Microfilament Proteins - metabolism; Microscopy, Electron; Morphology, structure, chemical composition; PARP protein; Phalloidine - metabolism; Proteins - analysis; Proteins - physiology; Species Specificity; Spectrometry, Fluorescence; Swine
• ISSN: 1350-0872; 1465-2080
• DOI: 10.1099/00221287-145-11-3235

A group of prokaryotic actin-related proteins (PARP) with an M(r) of 43000 was detected in Actinobacillus pleuropneumoniae. These proteins were enriched by a depolymerization/polymerization cycle, under similar conditions to those used to polymerize muscle actin, and purified by affinity chromatography on a DNase I-Sepharose column. Three isoforms of A. pleuropneumoniae PARP (Ap-PARP) with pl values of 5.8, 6.15 and 6.2 were detected. Ap-PARP were recognized by four different anti-actin antibodies (one anti-muscle and three anti-cytoplasmic isoforms). Ap-PARP were also recognized by antibodies against Anabaena variabilis PARP (Av-PARP) and against actin-binding proteins such as alpha-actinin and spectrin, and also by a monoclonal antibody against heat-shock cognate protein 70 (Hsc70). Specific binding of phalloidin to Ap-PARP was detected both in permeabilized cells and in vitro. Purified Ap-PARP can polymerize under similar conditions to those required for skeletal muscle actin polymerization and the filaments formed appear to be decorated with myosin subfragment-1 (S1) as observed by transmission electron microscopy. The amino acid composition of Ap-PARP revealed more similarities to muscle gamma-actin and the cytoplasmic beta-actin isoform than to eukaryotic actin-related proteins.