Digestion of 7S antibodies with papain and pepsin results in the formation of fragments which retain biological activity. I t has been demonstrated by Porter that papain in the presence of cysteine splits the molecule into three fragments of about equal size with a sedimentation coefficient of 3.5S and a molecular weight of approximately 50,000 (1). Digestion of the 7S gamma globulin with pepsi...

Consumption of kiwifruit is reported to relieve symptoms of functional gastrointestinal (GI) disorder. The effect may be related to the proteases in kiwifruit. This in vitro study aimed to measure protein hydrolysis due to kiwifruit protease under gastric and duodenal conditions. A sequence of experiments incubated meat protein, with and without kiwifruit, with varying concentrations of pepsin ...

A pepsin antibody fragmentation procedure was trialed and optimised. The procedure used was a modified version of that described in Current Protocols in Immunology. Pilot digestions using a range of pepsin concentrations and incubation times were completed at pH 4.0 and pH 4.5. The digestion products were examined by Phastgel electrophoresis, and the combination of pepsin concentration, incubat...

Kinoshita, Mine, Eisuke Kume, Shigeki Igarashi, Nobuko Saito, and Hiroshi Narita. Role of salivary mucin in the protection of rat esophageal mucosa from acid and pepsin-induced injury. Am. J. Physiol. 277 (Gastrointest. Liver Physiol. 40): G796–G800, 1999.—The mucosal defensive mechanisms of the esophagus against acid and pepsin remain to be elucidated. In the present study, we investigated the...

A strategy for the proteolytic fragmentation of human IgM has been developed. This method is called "cold pepsin digestion" because of its unique feature of achieving restricted peptic cleavages at 4 degrees and pH 4.0. Cold pepsin digestion has been applied successfully to produce an Fv fragment from 14 human IgM proteins. The Fv fragment consists of the heavy chain variable domain (VH) and th...

Limited pepsin digestion of human plasma albumin at pH 3.5 and 0 degrees in the presence of octanoate caused cleavage at residue 307 of the albumin molecule to yield two fragments. Thw two fragments corresponding to the NH2- and the COOH-terminal halves of the molecule were isolated in yields of about 15%. The COOH-terminal fragment is a mixture in which about 85% of the molecules had an additi...

Pepsin is common digestive enzyme used for fish digestion in the laboratory to collect trematode metacercariae. In a field study, to survey the infected fish is needed a huge yield of pepsin and it is very expensive. Therefore, our purpose of this study was to investigate the candidate enzyme from pineapple juice which has a digestive enzyme called bromelain, a mixture of proteolytic enzymes, t...

Capturem Pepsin was developed for rapid and efficient digestion of antibodies—with a room-temperature protocol (Figure 1)—designed for downstream proteomics analysis. Pepsin is an acidic protease with utility in a wide variety of applications, most notably in antibody sample preparation for characterization by mass spectrometry (MS). The specificity (Keil, B. 1992) and activity of digestion are...

One of the most striking peculiarities of enzyme action is the fact that the activity of the enzyme is limited to a definite range of acidity. If the solution is more or less acid than this the enzyme is practically inactive. SSrensen 1 showed that for a number of enzymes the determiuing factor was the hydrogen ion concentration and not the total acidity of the solution. In attempting to accoun...

7S sheep antibody is similar to 7S rabbit antibody, insofar as it too can be digested with pepsin to yield a 5S fragment still capable of precipitating homologous antigen. The 5S fragment from rabbit as well as sheep antibody is capable of fixing guinea pig complement. However, this fixation differs from the fixation by 7S antibody, since preformed antibody-antigen aggregates containing either ...