Open AccessPurification and characterization of a novel enzyme, L ‐ threo ‐3‐hydroxyaspartate dehydratase, from Pseudomonas sp. T62
Author(s) -
Wada Masaru,
Matsumoto Tomoko,
Nakamori Shigeru,
Sakamoto Mitsuru,
Kataoka Michihiko,
Liu JiQuan,
Itoh Nobuya,
Yamada Hideaki,
Shimizu Sakayu
Publication year - 1999
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1999.tb08720.x
Subject(s) - dehydratase , enzyme , hydroxylamine , biochemistry , pyridoxal phosphate , stereochemistry , lyase , biology , chemistry , cofactor
L ‐ threo ‐3‐Hydroxyaspartate dehydratase ( L ‐ threo ‐3‐hydroxyaspartate hydro‐lyase), which exhibited specificity for L ‐ threo ‐3‐hydroxyaspartate ( K m =0.74 mM, V max =37.5 μmol min −1 (mg protein) −1 ) but not for D ‐ threo or D,L ‐ erythro ‐3‐hydroxyaspartate, was purified from a cell‐free extract of Pseudomonas sp. T62. The activity of the enzyme was inhibited by hydroxylamine and EDTA, which suggests that pyridoxal 5′‐phosphate and divalent cations participate in the enzyme reaction. The NH 2 ‐terminal amino acid sequence showed significant similarity to the Saccharomyces cerevisiae YKL218c gene product, a hypothetical threonine dehydratase. However, the purified enzyme showed no threonine dehydratase activity.