Amide hydrogen/deuterium exchange (H/D exchange) coupled with mass spectrometry has been widely used to analyze the interface of protein-protein interactions, protein conformational changes, protein dynamics and protein-ligand interactions. H/D exchange on the backbone amide positions has been utilized to measure the deuteration rates of the micro-regions in a protein by mass spectrometry(1,2,3...

A miniaturized pepsin reactor was prepared inside a fused-silica capillary (i.d. 75 microm) by coating a pepsin-containing gel on a photopolymerized porous silica monolith. The pepsin-encapsulated film was prepared by a sol-gel method. The sol-gel reaction was optimized so that the sol solution containing pepsin forms a thin film on the photopolymerized sol-gel (PSG) monolith that was initially...

Anthocyanins are effective antioxidants but they have also been proposed to have other biological activities independent of their antioxidant capacities that produce health benefits. Examples range from inhibition of cancer cell growth in vitro, induction of insulin production in isolated pancreatic cells, reduction of starch digestion through inhibition of a-glucosidase activity, suppression o...

Platelet destruction in chronic immune thrombocytopenic purpura (ITP) is due either to antibody against platelet-associated antigen(s) that attaches by the antigen-specific Fab portion of the molecule or to platelet-bound immune complexes that bind nonspecifically to a platelet Fc receptor. Since pepsin digestion destroys the Fc fragment, the effect of this agent on platelet binding should allo...

In vitro digestion products of proteins were compared among beef, pork, chicken, and fish. Gastric and jejunal contents from the rats fed these meat proteins were also compared. Cooked pork, beef, chicken, and fish were homogenized and incubated with pepsin alone or followed by trypsin. The digestion products with molecular weights of less than 3000 Da were identified with MALDI-TOF-MS and nano...

Purified streptococcal M protein vaccines often produce non-type-specific immunotoxic reactions in the skin or the blood of humans. In an attempt to free the type-specific M antigen (TSM) of such non-type-specific (NTSM) immunotoxic properties, purified M protein preparations were subjected to brief periods (5 to 10 min) of enzymatic digestion in dilute solutions of pepsin (20 mug/ml) at pH 5.0...

1. Evidence has been found that Northrop's phenomenon (so called by us) is produced in the digestion of casein or hemoglobin brought about by trypsin, papain, and pepsin either crude or crystalline in the presence of gelatin. 2. Anson's and Kunitz' methods permit the measure of proteolytic activity of any protease on casein or hemoglobin substrate in the presence of gelatin, even in very small ...

This study aimed to understand the structural devolution of 10% w/w rennet-induced (RG) and transglutaminase-induced acid (TG) gels in H2O D2O under vitro gastric conditions with without pepsin. The real-time structure at a nano- (e.g. colloidal calcium phosphate (CCP) micelle) micro- (gel network) level was determined using ultra-small (USANS) small-angle neutron scattering (SANS) electron mic...

Pepsin has been employed successfully in conjunction with other proteolytic enzymes for the degradation and structural determination of insulin (1, 2), corticotropin (3), ribonuclease (4), and tobacco mosaic virus (5). Because of the difference in specificity between this enzyme and chymotrypsin (6), it was thought that pepsin would hydrolyze some bonds not attacked by chymotrypsin and perhaps ...