Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.4.16.2 (
PCP
)
3,761
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The effect of the ADP receptor antagonists ATP and adenosine 5'-(beta, gamma-methylene)triphosphate (AMP-
PCP
), and the ADP-utilizing enzyme systems creatine phosphokinase/creatine phosphate (CPK/CP) and pyruvate kinase/phosphoenol pyruvate (PK/
PEP
) on platelet deposition onto type I collagen was examined. An in vitro perfusion system was used, which allowed continuous visualization of the deposition of fluorescently labelled platelets. This system also provide well-controlled rheology, precise quantification of deposition, and allowed the use of heparinized whole human blood (3 u/ml). Heparinization at this level permits the local generation of thrombin near surface platelet aggregates. The contribution of ADP is thus studied with the combined effects of thrombin, thromboxane A2, and other aggregating agents present. Results from these studies indicate that ATP was capable of inhibiting deposition by 60% at 1 microM and 90% at 5 microM (whole blood conc.). AMP-
PCP
inhibited deposition in a dose dependent manner with a Ki of approximately 80 microM and a maximum inhibition of 60%. Inhibition by CPK/CP was measured at 20, 40, and 60 u/ml, with approximately 45% inhibition achieved for the latter two concentrations. PK/
PEP
at 60 u/ml resulted in 70% inhibition. These results support a role for ADP in mediating platelet recruitment in thrombus growth on collagen. Previous work utilizing animal bleeding times supports this conclusion; the present study demonstrates that this role is not dependent upon endothelial or vasoconstrictive effects. Intraplatelet cAMP levels were raised with respect to controls upon exposure to ATP at 8.3 microM (p less than 0.025), and 15 microM (p less than 0.005), as well as AMP-
PCP
at 42-500 microM (p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:ADP receptor antagonists and converting enzyme systems reduce platelet deposition onto collagen. 132 10
Various food proteins including, e.g. gluten, collagen and casein are rich in L-proline residues. Due to the cyclic structure of proline, these proteins are well protected from enzymatic degradation by typical digestive enzymes. Proline-specific peptidases (PsP) belong to different families of hydrolases acting on peptide bonds (EC 3.4.x.x). They occur in various organisms including bacteria, fungi, plants and insects. Based on their biochemical characteristics, PsP type enzymes are further grouped into different subclasses of which prolyl aminopeptidases (EC 3.4.11.5, PAP), prolyl carboxypeptidases (EC 3.4.17.16,
PCP
) and prolyl oligopeptidases/prolyl endopeptidases (EC 3.4.21.26, POP/
PEP
) are of major interest for applications in food biotechnology. This mini review summarises the biochemical assays employed for these subclasses of PsP and their structural properties and the reaction mechanisms. A special focus was set on PsP derived from fungi and insects and important industrial applications in the field of food biotechnology. The degradation of gluten and collagen as well as the hydrolysis of bitter peptides are discussed.
...
PMID:Prolyl-specific peptidases for applications in food protein hydrolysis. 2623 67