Thermotolerant alkaline protease enzyme from Bacillus licheniformis A10: purification, characterization, effects of surfactants and organic solvents

Abstract

In this study, the extracellular thermostable alkaline protease out of A10 strain was purified 1.38-fold with 9.44% efficiency through the ammonium sulfate precipitation-dialysis and DE52 anion exchange chromatography methods. The molecular weight of the enzyme in question along with sodium dodecyl sulfate-polyacrylamide gel electrophoresis was determined to be approximately 40.55 kDa, whereas the optimum pH and temperature ratings were identified as 9.0 and 70 °C, respectively. It was seen that the enzyme had remained stable between pH 7.5-10.5 range, protecting more than 90% of its activity in the wake of 1 h incubation at 60-70 °C. It was also observed that the enzyme enhanced its activity in the presence of Mg(2+), Mn(2+), K(+), while Fe(2+), Ni(2+), Zn(2+), Ag(+ )and Co(2+ ) decreased the activity. Ca(2+), however, did not cause any change in the activity. The enzyme was seen to have been totally inhibited by phenylmethylsulfonyl fluoride, therefore, proved to be a serine alkaline protease.

A novel alkaline protease from alkaliphilic Idiomarina sp. C9-1 with potential application for eco-friendly enzymatic dehairing in the leather industry

“…AprA exhibits higher optimal pH (10.5) and better stability under alkaline conditions than many previously reported alkaline proteases from Bacillus 4 , 6 , 8 , 9 , 15 , 16 , 27 , 33 , 51 , 56 – 61 , Vibrio 19 , Aspergillus 21 , 62 , 63 , Thermoactinomyces 24 , 26 , Streptomyces 25 , Thermus 28 , Pseudoalteromonas 41 , Alteromonas 42 , Stenotrophomonas 44 , Trametes 52 , Termitomyces 54 , Virgibacillus 64 , Caldicoprobacter 65 , Hirsutella 66 , Scopulariopsis 67 , and Penicillium 68 (Table S1 ). Furthermore, AprA also retains high activity and stability over a wide range of pH (7.0–11.5) and temperature (40–70 °C), several metal ions, surfactants and some oxidizing and reducing agents.…”

SHG10 keratinolytic alkaline protease from Bacillus licheniformis SHG10 DSM 28096: Robust stability and unusual non‐cumbersome purification

“…EMB9, and B. licheniformis 3C5, displaying perceivable activity at extremists pH(s) (10-12) and temperatures (60-75°C) [16,24,[39][40][41][42]. Like other proteases reported in the literature [25,[43][44][45]49], SHG10 keratinolytic protease exhibited similar profile for pH stability under wide range of pH (6-10) for extended hours. This pH stability profile would in turn impose an additional industrial value of this enzyme.…”

“…Like other alkaline proteases reported in the literature [9,11,25,38,44,49,51], SHG10 keratinolytic protease is a serine protease type as majority of its activity (86%) was lost in presence of 3 mM PMSF. In contrast, EDTA, a neutral protease inhibitor, did not impose an inhibitory effect on enzyme activity but stimulated the activity at a concentration of 10 mM.…”

Biochemical characteristics of a novel protease from the basidiomycete Amanita virgineoides

“…Some metal ions, such as Cd 2+ , Cu 2+ , Fe 3+ , and Hg 2+ ions, engendered a substantial loss of protease activity, but Mg 2+ , Ca 2+ , and K + ions augmented protease activity to some extent. Although metal ions may exert different effects on proteases from various resources, in general, Hg 2+ ions usually brought about loss in activity [11,40,41,46,49,50], and Mg 2+ , Ca 2+ , and K + ions were the most promising metal ions that could heighten protease activity [25,46,47,57]. In the current study, some intriguing results were observed from treatments under Pb 2+ , Mn 2+ , and Al 3+ .…”