Purification and characterization of alkaline protease from Alcaligenes faecalis

Abstract

Extracellular alkaline protease from the alkalophilic bacterium Alcaligenes faecalis was purified by a combination of ion-exchange and size-exclusion chromatographic methods, and its properties were examined. The purified enzyme had a specific activity of 563.8 micromol of tyrosine/min per mg of protein and gave a single band on native PAGE and SDS/PAGE with a molecular mass of 67 kDa. Gelatin zymogram also revealed one clear zone of proteolytic activity which corresponded to the band obtained with native PAGE and SDS/PAGE. The enzyme had an optimal pH of 9.0 and exhibited its highest activity at 55 degrees C. The enzyme activity was inhibited by PMSF, suggesting the presence of serine residues at the active site. The enzyme had a K(m) of 1.66 mg/ml and a V(max) of 526 units/min per mg of protein with casein as the substrate.

Production and Characterization of Bacteriocin Produced by Lactobacillus Viridescence(NICM 2167)

“…Bacteriocin production from Lactobacillusviridescence (NCIM 2167) is novel source which has not been investigated so far. (Drapeau et al 1972;Brunder et al 1997;Anwar and Saleemuddin 1998;Thangam and Rajkumar 2002;Bhagwat et al 2015).Thus it clearly shows that only few proteases could break down the bacteriocin as per their specificity towards respective bacteriocin. Amongst Escherichia coli showed the better results, hence it is used for further studies.Bacteriocin from culture supernatant showed the total activity of 6.2×10 8 AU/mL (Table2).…”

Regeneration of static-load-degenerated articular cartilage extracellular matrix by vitamin C supplementation

“…The protease activity in the CM and FRM fractions of chondrocyte-synthesized matrix was assayed by casein hydrolysis as described by Thangam and Rajkumar (2002). Casein was used as a substrate for the assay of cartilage proteases in earlier studies (Tortorella and Arner 1997;Treadwell et al 1986).…”

A Serine Protease Gene from the Firefly, Pyrocoelia rufa: Gene Structure, Expression, and Enzyme Activity

“…Proteases are important industrial enzymes accounting for nearly 60% of total world wide enzyme market (Seong et al 2004). Proteases from various sources have been exploited biotechnologically: in the leather industry as an unhairing agent; in the commercial development of laundry detergents; in the removal of toxic reagents used in the pharmaceutical industry; and in the improvement of biological control agents through genetic engineering (Kim et al 1999, Chung et al 2001, Thangam & Rajkumar 2002, Seong et al 2004). Thus, the great economic value of proteases still gives an impetus to search for ones with novel properties.…”