Nattokinase (Subtilisin NAT, NK) is a bacterial serine protease with high fibrinolytic activity. To probe their roles on protease activity and substrate specificity, three residues of S3 site (Gly(100), Ser(101) and Leu(126)) were mutated by site-directed mutagenesis. Kinetics parameters of 20 mutants were measured using tetrapeptides as substrates, and their fibrinolytic activities were determ...

The evolution of digestive proteases during larval development of Rhynchophorus ferrugineus (Olivier, 1790) has been studied. A progressive increase of protease activity has been found. The optimum pH for proteolytic activity against azocasein was determined. Caseinograms revealed an active complex of alkaline proteases from the early stages of the development. From the apparent molecular masse...

The gene (trprl) encoding alkaline serine protease (Aprl; subtilase) from Atteremonas sp. strain O-7 was cloned and sequenced. The nucleotide sequence of tu7rl has been identified. The deduced arnino acid sequence indicated that uprl codes for a precursor of 715 amino acids and the precursor is composed of four regions including a signal peptide, an N-terminal pro-region, a mature protease regi...

Asthma, a common disorder that affects >250 million people worldwide, is defined by exaggerated bronchoconstriction to inflammatory mediators including acetylcholine (ACh), bradykinin and histamine-also termed airway hyper-responsiveness. Nearly 10% of people with asthma have severe, treatment-resistant disease, which is frequently associated with immunoglobulin-E sensitization to ubiquitous fu...

The gene (aprI) encoding alkaline serine protease (AprI; subtilase) from Alteromonas sp. strain O-7 was cloned and sequenced. The nucleotide sequence of aprI has been identified. The deduced amino acid sequence indicated that aprI codes for a precursor of 715 amino acids and the precursor is composed of four regions including a signal peptide, an N-terminal pro-region, a mature protease region ...

Previously, we isolated an ATP-dependent proteolytic pathway in muscle, liver, and reticulocytes that requires ubiquitin and the enzymes which conjugate ubiquitin to proteins. We report here that skeletal muscle contains another soluble alkaline energy-dependent (but ubiquitin-independent) proteolytic activity. The cleavage of non-ubiquitinated protein substrates by the partially purified prote...

A highly sensitive and specific radioimmunoassay has been developed for Pseudomonas aeruginosa alkaline protease. Production of alkaline protease was found to be strain variable and medium dependent.

Alkaline crude enzymes from the viscera of the Tunisian barbel (Barbus callensis) were extracted and characterized. Proteolytic crude extract from barbel viscera was active and stable in alkaline solution. The optimum pH and temperature were 11.0 and 55 °C, respectively, using casein as a substrate. The crude alkaline protease was extremely stable in the pH range of 5.0-12.0. Zymography activit...

Alkaline crude enzymes from the viscera of the Tunisian barbel (Barbus callensis) were extracted and characterized. Proteolytic crude extract from barbel viscera was active and stable in alkaline solution. The optimum pH and temperature were 11.0 and 55 °C, respectively, using casein as a substrate. The crude alkaline protease was extremely stable in the pH range of 5.0-12.0. Zymography activit...

A novel enzyme-responsive hydrogel drug delivery system was developed with the potential to treat inflammation locally. Human neutrophil elastase (HNE) is a serine protease secreted by neutrophils which are the first cells recruited to inflammatory sites. We exploited this cell-secreted enzyme as a biological cue for controlled release. HNE sensitive peptide linkers were immobilized within poly...