ISSN:
0006-3592
Keywords:
purification
;
inositol monophosphatase
;
lithium
;
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
myo-Inositol monophosphate phosphatase (IMPase) has been purified 888-fold to apparent homogeneity from procine brains. The purification procedure involves: homogenization, ammonium sulfate fractionation, and a number of ion-exchange and gel-filtration chromatography steps. The purified enzyme exhibited a final specific activity of 932 nmol · min-1 · mg-1. The molecular mass of the enzyme was estimated to be 29kDa by SDS poly-acrylamide gel electrophoresis and 58 ± 5 kDa by HPLC gel filtration in 10mM Tris-HCI, pH 7.4. Kinetic measurements have shown that the apparent Km value of the phosphatase for the utilization of inositol-1-phosphate and β-glycerol phosphate are 3.20 × 10-4 and 8 × 10-3 M, respectively. Similar to the same enzyme isolated from bovine brains, the porcine brain enzyme has been shown to be inhibited by lithium. The K1 was determined to be 6.38 × 10-4 M and the inhibition is uncompetitive. © 1995 John Wiley & Sons, Inc.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bit.260480517
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