Gibbs M D, Elinder A U, Reeves R A, Bergquist P L
Centre for Gene Technology, School of Biological Sciences, University of Auckland, New Zealand.
FEMS Microbiol Lett. 1996 Jul 15;141(1):37-43. doi: 10.1111/j.1574-6968.1996.tb08360.x.
A gene encoding a beta-mannanase (manA) has been cloned from an obligately anaerobic extreme thermophile, Caldicellulosiruptor strain Rt8B.4, which is most closely related to Caldicellulosiruptor saccharolyticus (formerly Caldocellum saccharolyticum). The gene codes for a multidomain enzyme with a C-terminal beta-mannanase domain which was amplified by the polymerase chain reaction and cloned into a temperature-inducible expression vector in Escherichia coli. Sequence comparisons have shown that the Man domain of Rt8B.4 ManA is related to a thermophilic Dictyoglomus mannanase and a mesophilic mannanase from a Bacillus species. It appears to be unrelated to the beta-mannanase domain of C. saccharolyticus, implying acquisition of the genes from unrelated sources by the two bacteria.
已从专性厌氧极端嗜热菌热纤维梭菌菌株Rt8B.4中克隆出一个编码β-甘露聚糖酶（manA）的基因，该菌株与嗜糖热纤维梭菌（原解纤维素嗜热栖热菌）关系最为密切。该基因编码一种多结构域酶，其C端β-甘露聚糖酶结构域通过聚合酶链反应进行扩增，并克隆到大肠杆菌的温度诱导表达载体中。序列比较表明，Rt8B.4 ManA的Man结构域与嗜热网团菌甘露聚糖酶和芽孢杆菌属的嗜温甘露聚糖酶相关。它似乎与嗜糖热纤维梭菌的β-甘露聚糖酶结构域无关，这意味着这两种细菌从无关来源获得了这些基因。
