The extracellular cysteine protease from Streptococcus pyogenes is a virulence factor that plays a significant role in host-pathogen interaction. Streptococcal protease is expressed as an inactive 40-kDa precursor that is autocatalytically converted into a 28-kDa mature (active) enzyme. Replacement of the single cysteine residue involved in formation of the enzyme active site with serine (C192S...

A second extracellular protease from myxobacter strain AL-1 has been purified to homogeneity and named protease II; the enzyme crystallizes as fine needles. The extracellular, cell wall lytic protease reported previously from the same organism is now designated protease I. Protease II exhibits a pH optimum of 8.5 to 9.0 and is stable from pH 3.0 to 9.0. The enzyme is heat stable at 50 C for 18 ...

Proteases are catabolic enzymes that catalyze the complete hydrolysis of protein. They constitute one of the most important groups of industrial enzymes, accounting for nearly 60% of the total worldwide enzyme sale1. Keratinolytic protease is a specific protease that has immense commercial importance. It acts on keratin of the hides thus can be used in dehairing2. This enzyme along with proteas...

The recognition of lysine-type peptidoglycans (PG) by the PG recognition complex has been suggested to cause activation of the serine protease cascade leading to the processing of Spätzle and subsequent activation of the Toll signaling pathway. So far, two serine proteases involved in the lysine-type PG Toll signaling pathway have been identified. One is a modular serine protease functioning as...

A protease producing microorganism was isolated from soil collected from a detergent industry and identified as Bacillus species. Isolate K-30 produced thermostable alkaline protease utilizing rice bran. The optimum conditions for protease activity was 55°C at pH 9 with 4% inoculum in the medium containing 1% rice bran after 96 h of incubation. Beef extract, tryptone and yeast extract were good...

Active acid protease was found in serum-free spent medium of human pancreatic carcinoma cell line HPC-YT. These cells have been maintained for over 215 generations in a serum-free, chemically defined medium. Acid protease was partially purified about 3000-fold by Mono Q ion-exchange chromatography, pepstatin-aminohexyl-Sepharose affinity chromatography, hydroxylapatite affinity chromatography, ...

A new protease was found in mitochondria of bone marrow cells. The protease was purified from human bone marrow cells by using the following methods: disruption of cells by sonication; buffer extraction; column chromatography using DEAE-cellulose, Sephadex G-75, and CM-cellulose. It was then crystallized in the presence of polyethylene glycol. The crystallized enzyme is homogeneous as judged by...

Because of its stringent sequence specificity, the catalytic domain of the nuclear inclusion protease from tobacco etch virus (TEV) is a useful reagent for cleaving genetically engineered fusion proteins. However, a serious drawback of TEV protease is that it readily cleaves itself at a specific site to generate a truncated enzyme with greatly diminished activity. The rate of autoinactivation i...

An alkaline protease producing strain was isolated from the sample collected from a slaughter house in Krishnagiri (District), T.N., India identified as Bacillus subtilis. Optimization of process parameters, surfactants as stimulants and strain improvement by UV for increased production of protease was carried out. Further the enzyme was partially purified and characterized. The most important ...

Protease activity has been demonstrated in culture supernatants of Clostridium tetani at various stages of fermentation. Gel chromatography of the concentrated filtrates revealed the presence of three enzymatically active fractions eluting at separate positions off the column. The smallest protease was found to "nick" the single chain intracellular tetanus toxin, producing the extracellular, tw...