Nucleoside diphosphate kinase from psychrophilic sp. AS-131 isolated from Antarctic Ocean

Yonezawa, Yasushi*; Nagayama, Aiko*; Tokunaga, Hiroko*; Ishibashi, Matsujiro*; Arai, Shigeki; Kuroki, Ryota; Watanabe, Keiichi*; Arakawa, Tsutomu*; Tokunaga, Masao*

Nucleoside diphosphate kinase isolated from psychrophilic sp. AS-131 (ASNDK) was expressed in and purified to homogeneity. Comparing to mesophilic NDK isolated from , ASNDK exhibited highly elevated thermolability: (1) expression at 37C as a denatured insoluble form, and (2) 30C lower optimum temperature of enzymatic activity. The subunit structure of ASNDK was suggested to be dimer, as in NDKs isolated from moderate halophiles.