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:4.2.2.7 (
heparinase
)
1,270
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The serine protease,
prostate-specific antigen
(
PSA
), its protein substrates, semenogelin (Sg) I and II, and protein C inhibitor (PCI) have been described as components of human seminal plasma. PCI was found to inhibit the
PSA
-catalyzed degradation of insoluble coagula Sg I + II by forming a
PSA
-PCI complex. Digestion of seminal coagula with
PSA
released PCI and
PSA
-PCI complex from the coagula into a soluble phase, suggesting the presence of active PCI binding to the coagula. To investigate the molecular interaction of Sg with
PSA
and PCI, we purified Sg II from seminal coagula as a soluble form and found that Sg II is glycosylated with heterogeneous carbohydrate moieties. Sg II bound to the solid-phase complex of diisopropylfluorophosphate (iPr2FP) and
PSA
with an apparent dissociation constant (kd) of 41 nM and to PCI with a Kd of 28 nM. The binding of Sg II to iPr2P-
PSA
was not affected by PCI and that of Sg II to PCI was not affected by iPr2P-
PSA
, suggesting that Sg II forms a ternary complex with
PSA
and PCI. The bindings of Sg II to both iPr2P-
PSA
and PCI were influenced by pH, ionic strength, heparin, dextran sulfate, and divalent cations, particularly by Zn2+. Treatment of Sg II with
heparinase
, heparitinase, N-glycanase, or with O-glycanase following sialidase did not affect the binding of Sg II to iPr2P-
PSA
and PCI. These findings suggested that PCI bound to Sg in seminal vesicles regulates the
PSA
-catalyzed degradation of Sg in seminal plasma, and that the binding of PCI and
PSA
to Sg is modulated by several factors such as pH, ionic strength, divalent cations, and heparin-like substances in seminal plasma.
...
PMID:Characterization of semenogelin II and its molecular interaction with prostate-specific antigen and protein C inhibitor. 866 56