Abstract

The rat uterine secretory enzyme glycerylphosphorylcholine (GPC) diesterase (EC 3.1.4.2) had been purified and characterized previously with respect to its mol. wt., size, amino acid, carbohydrate composition and estrogen inducible properties. This enzyme is observed to have exclusive specificity for GPC and exhibits characteristic hyperbolic kinetics with Ca2+ in an ethyleneglycolbis N'N'N'N' tetraacetic acid (EGTA) buffered system. Ca2+ reduces Km of the enzyme for GPC from 0.65 to 0.25 mM. The Km for GPC of the partially purified enzyme is found to be 0.35 mM without addition of calcium which indicates the presence of a positive modulator of the enzyme in this fraction. Based on this rationale, a protein activating factor for the enzyme was isolated from this fraction which has a native size of 18 KD as observed on Sephacryl S-200 chromatography and strikingly stimulates enzyme activity at around 0.55 microM.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.