来自戴尔有孢圆酵母CBS 2923的一种新型植酸酶对肌醇六磷酸的完全水解作用

Complete hydrolysis of myo-inositol hexakisphosphate by a novel phytase from Debaryomyces castellii CBS 2923.

作者信息

Ragon Mélanie, Aumelas André, Chemardin Patrick, Galvez Santiago, Moulin Guy, Boze Hélène

机构信息

Equipe Génie Microbiologique et Enzymatique, SUPAGRO-INRA, 2 place Viala, 34060, Montpellier Cedex 01, France.

出版信息

Appl Microbiol Biotechnol. 2008 Feb;78(1):47-53. doi: 10.1007/s00253-007-1275-3. Epub 2007 Nov 29.

DOI:10.1007/s00253-007-1275-3

PMID:18046551

Abstract

Debaryomyces castellii phytase was purified to homogeneity in a single step by hydrophobic interaction chromatography. Its molecular mass is 74 kDa with 28.8% glycosylation. Its activity was optimal at 60 degrees C and pH 4.0. The K (m) value for sodium phytate was 0.532 mM. The enzyme exhibited a low specificity and hydrolyzed many phosphate esters. The phytase fully hydrolyzed myo-inositol hexakisphosphate (or phytic acid, Ins P(6)) to inositol and inorganic phosphate. The sequence of Ins P(6) hydrolysis was determined by combining results from high-performance ionic chromatography and nuclear magnetic resonance. D. castellii phytase is a 3-phytase that sequentially releases phosphate groups through Ins (1,2,4,5,6) P(5), Ins (1,2,5,6) P(4), Ins (1,2,6) P(3), Ins (1,2) P(2), Ins (1 or 2) P(1), and inositol (notation 3/4/5/6/1 or 2).

摘要

通过疏水相互作用色谱法一步将卡氏德巴利酵母植酸酶纯化至均一。其分子量为74 kDa，糖基化程度为28.8%。其活性在60℃和pH 4.0时最佳。植酸钠的K（m）值为0.532 mM。该酶表现出低特异性，能水解多种磷酸酯。该植酸酶将肌醇六磷酸（或植酸，Ins P(6)）完全水解为肌醇和无机磷酸。通过结合高效离子色谱和核磁共振的结果确定了Ins P(6)的水解顺序。卡氏德巴利酵母植酸酶是一种3-植酸酶，通过Ins (1,2,4,5,6) P(5)、Ins (1,2,5,6) P(4)、Ins (1,2,6) P(3)、Ins (1,2) P(2)、Ins (1或2) P(1)和肌醇（表示法3/4/5/6/1或2）依次释放磷酸基团。