Purification and characterization of dissimilatory nitrate reductase from a denitrifying halophilic archaeon, Haloarcula marismortui

FEBS Letters

Sakurai, Takeshi¹  Yoshimatsu, Katsuhiko²  Fujiwara, Taketomo² 

[1]Division of Life Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan

[2]Department of Biology and Geosciences, Faculty of Science, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan

关键词: Nitrate reductase;    Denitrification;    Halophilic archaeon;    Molybdenum;    Haloarcula marismortui;   

DOI  :  10.1016/S0014-5793(00)01321-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Dissimilatory nitrate reductase was purified from a denitrifying halophilic archaeon, Haloarcula marismortui, to an electrophoretically homogeneous state. The purified enzyme was inferred to be a homotetramer composed of a 63 kDa polypeptide. The electron paramagnetic resonance spectrum of the purified enzyme revealed typical rhombic signals which were ascribed to Mo(V) in the Mo–molybdopterin complex. Like the bacterial membrane-bound (Nar-) enzyme, the purified enzyme supported the catalysis of chlorate. The enzyme was activated in extreme saline conditions and the values of k _cat and K _m toward nitrate were 145 s⁻¹ and 79 μM, respectively, in the presence of 2.0 M NaCl.

【 授权许可】

Unknown