Monstadt G M, Holldorf A W
Institut für Physiologische Chemie, Ruhr-Universität Bochum, Germany.
Biochem J. 1991 Feb 1;273 ( Pt 3)(Pt 3):739-45. doi: 10.1042/bj2730739.
Arginine deiminase from the extreme halophilic archaebacterium Halobacterium salinarium was purified to homogeneity in a four-step procedure with a 310-fold enrichment. The enzyme consists of two identical subunits of 55 kDa; its native molecular mass is 105 kDa. The pI of 4.7 indicates that acidic nature of the protein, which is evidenced by its amino acid composition, which shows an excess of more than 15% of acidic amino acids. The N-terminal amino acid of the enzyme is lysine. Arginine deiminase from Halobacterium salinarium exhibits its highest catalytic activity in the presence of 3.5 M-NaCl, pH 7.6, and at 40 degrees C. The half-activity constant, Ks, for arginine is 3.1 mM. The enzyme is inhibited by ornithine.
采用四步纯化程序，将嗜盐古生菌盐生盐杆菌中的精氨酸脱亚氨酶纯化至同质，纯化倍数达310倍。该酶由两个相同的55 kDa亚基组成；其天然分子量为105 kDa。4.7的pI表明该蛋白质具有酸性性质，这一点由其氨基酸组成得到证实，其酸性氨基酸含量超过15%。该酶的N端氨基酸为赖氨酸。盐生盐杆菌的精氨酸脱亚氨酶在3.5 M NaCl、pH 7.6和40℃条件下表现出最高催化活性。精氨酸的半活性常数Ks为3.1 mM。该酶受鸟氨酸抑制。
