Purification and Characterization of Extracellular Gelatinolytic Protease from B acillus Amyloliquefaciens  H11

Abstract

Extracellular gelatinolytic enzyme from Bacillus amyloliquefaciens H11 was purified by gel filtration chromatography on Sephacryl S‐200 and ion exchange chromatography on diethylaminoethyl‐cellulose with 35% yield and 14‐fold increase in purity. Based on sodium dodecyl sulfate–polyacrylamide gel electrophoresis, the molecular weight of the purified enzyme was estimated to be 21 kDa. The optimum gelatinolytic activities of purified enzyme toward porcine gelatin were 50C and pH 8.0. The inhibitor study revealed that the purified enzyme was a metallo‐serine protease and activated by Ca2+ and Mg2+ but resistant to Triton X‐100 and methanol at a concentration of 10% (v/v). Among all gelatins, that from unicorn leatherjacket fish skin was the most preferred for hydrolysis by the purified enzyme, in comparison with porcine and tilapia counterparts. Thus, the enzyme from B. amyloliquefaciens H11 could be used as a potential protease for production of gelatin hydrolysate. Practical Applications Extracellular protease from Bacillus amyloliquefaciens H11 plays a specific catalytic role in the hydrolysis of gelatin and can be used for production of gelatin hydrolysate with bioactivities. It can also be a potential alternative for commercial protease in conversion of marine processing by‐products to generate high value‐added products.

Characteristics of proteolytic microorganisms and their effects on proteolysis in total mixed ration silages of soybean curd residue

“…B. amyloliquefaciens and B. methylotrophicus were the most active isolates in both TMR silages of this experiment. Their activities were mainly with serine and metallo proteinases characteristics, and similar results were also obtained by Sai-Ut et al [31] before. Proteolytic strains of other Bacillus species were isolated in lower orders of magnitudes.…”

Biochemical Characterization and Functional Analysis of Heat Stable High Potential Protease of Bacillus amyloliquefaciens Strain HM48 from Soils of Dachigam National Park in Kashmir Himalaya

“…During the present study, the enzyme from B. amyloliquefaciens HM48 was stable with pH buffers ranging from acidic to alkaline (pH 6–12), thereby reflecting that the enzyme has a wide pH spectrum reaching its maximal activity at pH 8.0, and an analogous observation has been recorded by Guleria et al [ 75 ]. However, the enzyme under examination had a much wider alkaline pH range than many previously reported B. amyloliquefaciens species having pH in the range of 5.0–11 [ 27 ], 4.0–10 [ 10 ], 4.0–10 [ 72 ], 6.0–10 [ 83 ] and 6.0–11 [ 26 ]. On the other hand, the pH-dependent enzyme stability profile of B. amyloliquefaciens HM48 (pH 8–11) also did not display much variation in the residual activity of the enzyme, thereby suggesting stability of the enzyme in alkaline pH range.…”

Enzymatic extraction of starch from broken rice using freeze‐thaw infusion with food‐grade protease

“…The optimal pH of B. amyloliquefaciens proteases is pH 8.0. A slight decrease in activity was found in the alkaline pH range, and a more pronounced decrease was observed in the acidic pH range . BPN and PSP proteases show similar activities at pH 8.0 and 45°C.…”

“…B. amyloliquefaciens produces large amounts of extracellular neutral metallo‐serine protease and alkaline serine protease . A previous study reported that maximum proteolytic activity was observed at 50°C, and activity gradually decreased at higher temperatures . The optimal pH of B. amyloliquefaciens proteases is pH 8.0.…”