Cho H Y, Kim Y W, Kim T J, Lee H S, Kim D Y, Kim J W, Lee Y W, Leed S, Park K H
Research Center for New Bio-Materials in Agriculture and Department of Food Science and Technology, Seoul National University, Suwon, South Korea.
Biochim Biophys Acta. 2000 May 23;1478(2):333-40. doi: 10.1016/s0167-4838(00)00037-6.
An additional amylase besides the typical alpha-amylase was detected in the cytoplasm of Bacillus subtilis SUH4-2, an isolate from Korean soil. The corresponding gene encoded a maltogenic amylase, which hydrolyzed cyclodextrin or starch to maltose and glucose; pullulan to panose; acarbose to glucose and acarviosine-glucose. Maltogenic amylase of B. subtilis SUH4-2 transferred sugar molecules to form various branched oligosaccharides upon the hydrolysis of substrates. The enzyme existed in a monomer-dimer equilibrium with a molar ratio of 3:2 in 50 mM KH(2)PO(4)-NaOH buffer (pH 7.0). The maltogenic amylase is most likely to be associated with carbohydrate metabolism in the cytoplasm, since the nucleotide sequence of the gene was highly homologous to the yvdF gene of B. subtilis 168, which is located in a gene cluster involved in maltose/maltodextrin utilization.
从韩国土壤中分离得到的枯草芽孢杆菌SUH4-2的细胞质中检测到一种除典型α-淀粉酶之外的淀粉酶。相应基因编码一种生麦芽糖淀粉酶，该酶可将环糊精或淀粉水解为麦芽糖和葡萄糖；将支链淀粉水解为潘糖；将阿卡波糖水解为葡萄糖和阿洛糖-葡萄糖。枯草芽孢杆菌SUH4-2的生麦芽糖淀粉酶在水解底物时会转移糖分子以形成各种分支寡糖。在50 mM KH(2)PO(4)-NaOH缓冲液（pH 7.0）中，该酶以摩尔比为3:2的单体-二聚体平衡状态存在。生麦芽糖淀粉酶很可能与细胞质中的碳水化合物代谢相关，因为该基因的核苷酸序列与枯草芽孢杆菌168的yvdF基因高度同源，yvdF基因位于参与麦芽糖/麦芽糊精利用的基因簇中。
