Seyfried M, Daniel R, Gottschalk G
Institut fur Mikrobiologie der Georg-August-Universitat, Gottingen, Germany.
J Bacteriol. 1996 Oct;178(19):5793-6. doi: 10.1128/jb.178.19.5793-5796.1996.
The genes encoding coenzyme B12-dependent glycerol dehydratase of Citrobacter freundii were cloned and overexpressed in Escherichia coli. The B12-free enzyme was purified to homogeneity. It consists of three types of subunits whose N-terminal sequences are in accordance with those deduced from the open reading frames dhaB, dhaC, and dhaE, coding for subunits of 60,433 (alpha), 21,487 (beta), and 16,121 (gamma) Da, respectively. The enzyme complex has the composition alpha2beta2gamma2. Amino acid alignments with the subunits of the recently sequenced diol dehydratase of Klebsiella oxytoca (T. Tobimatsu, T. Hara, M. Sakaguchi, Y. Kishimoto, Y. Wada, M. Isoda, T. Sakai, and T. Toraya, J. Biol. Chem. 270:7142-7148, 1995) revealed identities between 51.8 and 70.9%.
弗氏柠檬酸杆菌中编码依赖辅酶B12的甘油脱水酶的基因被克隆并在大肠杆菌中过表达。不含B12的酶被纯化至同质。它由三种类型的亚基组成,其N端序列与从开放阅读框dhaB、dhaC和dhaE推导的序列一致,分别编码60433(α)、21487(β)和16121(γ)Da的亚基。酶复合物的组成为α2β2γ2。与最近测序的产酸克雷伯菌二醇脱水酶的亚基进行氨基酸比对(T. Tobimatsu、T. Hara、M. Sakaguchi、Y. Kishimoto、Y. Wada、M. Isoda、T. Sakai和T. Toraya,《生物化学杂志》270:7142 - 7148,1995年),发现同源性在51.8%至70.9%之间。