Myrmecophytic Acacia species produce food bodies (FBs) to nourish ants of the Pseudomyrmex ferrugineus group, with which they live in an obligate mutualism. We investigated how the FBs are protected from exploiting nonmutualists. Two-dimensional gel electrophoresis of the FB proteomes and consecutive protein sequencing indicated the presence of several Kunitz-type protease inhibitors (PIs). PIs...

pyruvate kinase is a key enzyme in glycolytic pathway that catalyzes the transphosphorylation between phosphoenolpyruvate and adp to yield atp and pyruvate. geobacillus stearothermophillus has a stable pyruvate kinase with determined crystal structure that composed of four separate domains. given that limited proteolysis experiments can be successfully used to probe conformational features of p...

An aspartic proteinase was isolated from American lobster gastric fluid. The purified cathepsin D runs as a single band on native-PAGE displaying proteolytic activity on a zymogram at pH 3.0, with an isoelectric point of 4.7. Appearance of the protein in SDS-PAGE, depended on the conditions of the gel electrophoresis. SDS treatment by itself was not able to fully unfold the protein. Thus, in SD...

Fish viscera have wide biotechnological potential as a source of digestive enzymes, especially proteinases. The biological diversity of fish species provides a wide array of enzymes with unique properties. Fish digestive proteolytic enzymes most commonly found include pepsin and trypsin. Those enzymes from fish viscera may have the advantages for the applications in the food industry since thei...

There is a simultaneous increase of both trypsinlike proteolytic activity and the number of granules in the convoluted granular tubules (CGT) of the rat submandibular gland (SMG) during postnatal development.1 Development and maintenance of the CGT granules and proteolytic activity are partially dependent on sex hormones, pituitary secretions, and thyroxine.14 Recently, five trypsinlike enzymes...

Bromelain is a complex mixture of proteinases typically derived from pineapple stem. Similar proteinases are also present in pineapple fruit. Beneficial therapeutic effects of bromelain have been suggested or proven in several human inflammatory diseases and animal models of inflammation, including arthritis and inflammatory bowel disease. However, it is not clear how each of the proteinases wi...

Total enzyme activity of whole viscera, and partial characterization of acidic proteases from Monterey sardine viscera are presented. Major proteolytic activity in alkali (pH 10) and minor activity in acid (pH 3) were detected. From purified acidic proteases, six fractions with high activity were selected. One fraction (42) showed one band on SDS–PAGE and two bands on isoelectrofocusing, with p...

The tarnished plant bug, Lygus hesperus Knight, is a pest that causes considerable economic losses to vegetables, cotton, canola, and alfalfa. Detailed knowledge of its digestive physiology will provide new opportunities for a sustainable pest management approach to control this insect. Little is known about the different protease class contributions to the overall digestion of a specific prote...

Correspondence to: Dr N Vergnolle, Mucosal Inflammation Research Group, Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Calgary, 3330 Hospital Drive NW Calgary, Alberta, Canada T2N4N1; [email protected] _________________________ O f all the body systems, the gastrointestinal tract is the most exposed to proteinases. Under physiological conditions, digestive pr...