Possible Interaction: Trypsin and Calcium Supplement

“By inhibition of protein synthesis with cycloheximide (2 microg/ml) the influence of trypsin on the anti-adhesive effect of CA 125 was significantly prolonged.”

“ Trypsin or gingipain-R also induced an increase in intracellular calcium concentration, and caused reciprocal cross desensitization.”

“These experiments further suggest that binding of Ca to E″ or removal of the NH2-terminal residues of the enzyme by trypsin induces a conformational change in the protein and makes the active site of the enzyme accessible to various metal ions rendering the enzyme active.”

“ Calcium (2 mM) increased by 10- to 1000-fold the trypsin and thrombin concentrations required to degrade Factor XIII to a 19-kDa peptide.”

“The results show that platelet and endothelial thrombospondins are both partially protected from trypsin digestion in the presence of calcium but have different trypsin and thermolysin fragmentation patterns.”

“Calcium was also found to affect the peptide pattern produced by limited tryptic digestion of thrombospondin, with some portions of the molecule being resistant to trypsin in the presence of calcium.”

“ Trypsin , triethanolamine, and heparin bind calcium ; therefore, their use is to be avoided.”

“ Calcium ion enhances conversion of trypsinogen to trypsin in pancreatic juice in many ways.”

“However, the addition of small amounts of calcium markedly enhances the conversion of trypsinogen to trypsin by trypsin.”

“…,Ca … trypsin or chymotrypsin, and a 50% reduction of the rate occurred at about 10-3 M. The effects of Ca on both tryptic and chymotryptic … suggestion is made that Ca acts to affect an equilibrium between two forms of fibrinogen, the one susceptible, the other inhibitory, to proteolysis.”

“It was shown in a preceding paper (6) that 0.01 M Ca++ produced a 25 per cent increase in the activity of trypsin towards synthetic substrates and this was interpreted in terms of an equilibrium between active and inactive trypsin that was shifted by Ca++.”