Temperature, organic solvent and pH stabilization of the neutral protease from Salinovibrio proteolyticus: significance of the structural calcium

• Published in: BMB reports Vol. 44; no. 10; pp. 665 - 668
• Main Authors: Mohsen Asghari, S., University of Guilan, Rasht, Iran, Khajeh, Khosro, Tarbiat Modares University, Tehran, Iran, Dalfard, Arastoo Badoei, Shahid Bahonar University of Kerman, Kerman, Iran, Pazhang, Mohammad, Azarbaijan University of Tarbiat Moallem, Tabriz, Iran, Karbalaei-Heidari, Hamid Reza, Shiraz University, Shiraz, Iran
• Format: Journal Article
• Language: English
• Published: Korea (South) 생화학분자생물학회 01.10.2011
• Subjects: AUTOLISIS; AUTOLYSE; AUTOLYSIS; Bacterial Proteins - chemistry; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Binding Sites; Calcium - chemistry; Calcium - metabolism; Enzyme Stability; Hydrogen-Ion Concentration; Neutral proteases; Organic solvent stability; Peptide Hydrolases - chemistry; Peptide Hydrolases - genetics; Peptide Hydrolases - metabolism; pH stability; Protein Conformation; Solvents - chemistry; Temperature; Thermostability; Vibrionaceae - enzymology; 화학
• ISSN: 1976-6696; 1976-670X
• DOI: 10.5483/BMBRep.2011.44.10.665

In order to clarify the impact of Ca-binding sites (Ca1 and 2) on the conformational stability of neutral proteases (NPs), we have analyzed the thermal, pH and organic solvent stability of a NP variant, V189P/A195E/G203D/A268E (Q-mutant), from Salinovibrio proteolyticus. This mutant has shown to bind calcium more tightly than the wild-type (WT) at Ca1 and to possess Ca2. Q-mutant was resisted against autolysis, thermoinactivation and pH denaturation in a Ca-dependent manner and exhibited better activity in organic solvents compared to the WT enzyme. These results imply that Ca1 and Ca2 are important for the conformational stability of NPs.