Molecular characterization of alkaline protease of Bacillus amyloliquefaciens SP1 involved in biocontrol of Fusarium oxysporum

作者：Guleria Shiwani^*; Walia Abhishek; Chauhan Anjali; Shirkot C K

来源：International Journal of Food Microbiology, 2016, 232: 134-143.

DOI：10.1016/j.ijfoodmicro.2016.05.030

• Cloning
• Structure Prediction
• Protease
• Bacillus amyloliquefaciens SP1
• Biocontrol
• Fusarium oxysporum

An alkaline protease gene was amplified from genomic DNA of Bacillus amyloliquefaciens SP1 which was involved in effective biocontrol of Fusarium oxysporum. We investigated the antagonistic capacity of protease of B. amyloliquifaciens SP1, under in vitro conditions. The 5.62 fold purified enzyme with specific activity of 607.69 U/mg reported 24.14% growth inhibition of F. oxysporum. However, no antagonistic activity was found after addition of protease inhibitor i.e. PMSF (15 mM) to purified enzyme. An 1149 bp nucleotide sequence of protease gene encoded 382 amino acids of 43 kDa and calculated isoelectric point of 929. Analysis of deduced amino acid sequence revealed high homology (86%) with subtilisin E of Bacillus subtilis. The B. amyloliquefaciens SP1 protease gene was expressed in Escherichiax coli BL21. The expressed protease was secreted into culture medium by E. colt and exhibited optimum activity at pH 8.0 and 60 degrees C. The most reliable three dimensional structure of alkaline protease was determined using Phyre 2 server which was validated on the basis of Ramachandran plot and ERRAT value. The expression and structure prediction of the enzyme offers potential value for commercial application in agriculture and industry.

• 出版日期2016-9-2