Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.26 (invertase)
 4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of four raw legume diets: field beans (Vicia faba) (RFB), navy beans (Phaseolus vulgaris) (RNB), soybeans (Glycine soja) (RSB) and bitter vetch (VICIA ervilia) (RBV), on disaccharidase activities in chick small intestine have been studied. Maltase and sucrase activities, which vary with age, were determined in 1 to 60 day old animals, RFB and RBV diets had no effect on maltase activity and only increased sucrase activity in 60 day old chicks. Both maltase and sucrase activities decreased in chicks on RSB diet, regardless of their age, and the decrease was even more pronounced in chicks on RNB diet. Contrarywise, chicks fed on autoclaved navy beans and soybeans showed a considerably higher activity of these disaccharidases.
 ...
PMID:Effect of raw legume diets on disaccharidase activity in the small intestine of chicks. 719 9

Raman optical activity (ROA) spectra have been measured for the proteins hen phosvitin, yeast invertase, bovine alpha-casein, soybean Bowman-Birk protease inhibitor, and rabbit Cd(7)-metallothionein, all of which have irregular folds in the native state. The results show that ROA is able to distinguish between two types of disorder. Specifically, invertase, alpha-casein, the Bowman-Birk inhibitor, and metallothionein appear to possess a "static" type of disorder similar to that in disordered states of poly(L-lysine) and poly(L-glutamic acid); whereas phosvitin appears to possess a more "dynamic" type of disorder similar to that in reduced (unfolded) lysozyme and ribonuclease A and also in molten globule protein states. In the delimiting cases, static disorder corresponds to that found in loops and turns within native proteins with well-defined tertiary folds that contain sequences of residues with fixed but nonrepetitive phi,psi angles; and dynamic disorder corresponds to that envisaged for the model random coil in which there is a distribution of Ramachandran phi,psi angles for each amino acid residue, giving rise to an ensemble of interconverting conformers. In both cases there is a propensity for the phi,psi angles to correspond to the alpha, beta and poly(L-proline) II (PPII) regions of the Ramachandran surface, as in native proteins with well-defined tertiary folds. Our results suggest that, with the exception of invertase and metallothionein, an important conformational element present in the polypeptide and protein states supporting the static type of disorder is that of the PPII helix. Long sequences of relatively unconstrained PPII helix, as in alpha-casein, may impart a plastic (rheomorphic) character to the structure.
Biopolymers 2001 Feb
PMID:Solution structure of native proteins with irregular folds from Raman optical activity. 1109 13