Metalloproteases Secreted by Actinobacillus suis

Abstract

Actinobacillus suis secretes metalloproteases into its medium. These secreted proteins, when concentrated by precipitation with 70% (NH4)2SO4 or methanol, displayed proteolytic activity at >200 kDa molecular mass bands in 10% polyacrylamide gels copolymerized with bovine casein (1%). They showed activity in a broad pH range (from pH 5 to pH 10) and were inhibited by 20 mM EDTA or EGTA, but could be reactivated by calcium. They were found heat stable at 40 degrees C, 50 degrees C, 60 degrees C, and 70 degrees C, but their activity diminished at 80 degrees C or higher. They degraded pig and bovine IgG and cross-reacted with a polyclonal serum against a high molecular mass secreted protease from A. pleuropneumoniae. Extracellular proteases could play a role in diseases caused by A. suis.

Actinobacillus suis and Actinobacillus equuli, emergent pathogens of septic embolic nephritis, a new challenge for the swine industry

“…Actinobacillus suis has been described to secrete metalloproteases in vitro and these proteins displayed proteolytic activity. Metalloproteases degrade pig and bovine IgG and they may have a role in diseases caused by A. suis (Negrete-Abascal et al 2004). Microbial proteases exert direct pathological effects by destroying host tissues and potentiate inflammatory processes.…”

Isolation and Screening of Thermo stable Extracellular Alkaline Protease Producing Bacteria from Tannery Effluents

“…There are some documents on the production of alkaline protease by Actinobacillus. According to Negrete-Abascal et al [21] Actinobacillus suis secretes metalloproteases into its medium.…”