Enterokinase is an enzyme secreted by the mucosa of the small intestine and is responsible for the conversion of trypsinogen to its active product, trypsin. Its key role in initiating the formation of proteolytic enzymes from their inactive precursors is illustrated in Fig. 1. When the pancreatic zymogens reach the duodenum, trypsin is formed by the action of enterokinase on trypsinogen and thi...

Enterokinase (enteropeptidase, EC 3.4.4.8) has been purified from porcine duodenal extracts by chromatography on DEAE-cellulose, carboxymethyl cellulose, Sephadex G-100, and Sephadex G-200. The final product was found to be homogeneous by a number of tests. Its specific activity against trypsinogen (nanomoles of trypsinogen activated per 30 min per mg) was 6550, which represented a 650-fold pur...

INTRODUCTION. WHILE previous work of the writer, upon the heat inactivation of trypsin, was in progress, it was shown by Waldschmidt-Leitz and Purr [1929] that trypsin itself is not an individual enzyme, but that it may be resolved into two components-a proteinase and a carboxypolypeptidase. It was found by these authors that the proteinase, although completely inactive alone, is capable, when ...

A method is described for the purification of porcine enterokinase by affinity chromatography with p-aminobenzamidine as the ligand. Purification was completed by immunoadsorption with antisera raised to components binding non-biologically to the gel. The final enterokinase preparation was 2.3 times more active than the most active preparation previously described.

Enterokinase is an enzyme secreted by the mucosa of the small intestine and is responsible for the conversion of trypsinogen to its active product, trypsin. Its key role in initiating the formation of proteolytic enzymes from their inactive precursors is illustrated in Fig. 1. When the pancreatic zymogens reach the duodenum, trypsin is formed by the action of enterokinase on trypsinogen and thi...

Previously, we found that expression by translational fusion of the polyhedrin (Polh)-green fluorescence protein (GFP) led to the formation of granular structures, and that these fluorescent granules were easily precipitated by high-speed centrifugation. Here, we developed an easy, fast, mass purification system using this baculovirus expression system (BES). An enhanced GFP (EGFP) fused with t...

Ethanol-associated fatty liver was induced in rats fed a nutritionally deficient liquid diet containing 36% of total calories as ethanol. Control rats received the same diet with sucrose substituted isocalorically for ethanol. After 40 days, hepatic lipid content of the ethanol-maintained animals was four-fold greater than controls and ultrastructural changes in hepatocytes were well establishe...

Intestinal enterokinase deficiency in 2 sibs in described. A boy failed to gain weight and had vomiting, diarrhoea, oedema, hypoproteinaemia, and anaemia in early infancy. His duodenal juice contained very low or absent proteolytic enzyme activity, which increased markedly after addition of enterokinase. He was treated with pancreatic extract and gained weight rapidly. At 44 months of age he is...

The optimization of enterokinase fermentation was performed with a recombinant Saccharomyces cerevisiae. The maximum enterokinase yield and specific yield were obtained when the ratio of yeast extract to bacto peptone was 5:5. However, the fraction of plasmid-containing cells was approximately 65% for most nitrogen source ratios. From batch cultures, the minimum DOT level was found to be a key ...

Cleavage and activation of hemagglutinin (HA) by trypsin-like proteases in influenza A virus (IAV) are essential prerequisites for its successful infection and spread. In host cells, some transmembrane serine proteases such as TMPRSS2, TMPRSS4 and HAT, along with plasmin in the bloodstream, have been reported to cleave the HA precursor (HA0) molecule into its active forms, HA1 and HA2. Some try...