Scholle R R, Coyne V E, Maharaj R, Robb F T, Woods D R
J Bacteriol. 1987 Jun;169(6):2685-90. doi: 10.1128/jb.169.6.2685-2690.1987.
A halotolerant collagenolytic Vibrio alginolyticus strain isolated from salted hides had intracellular sucrase activity and did not secret sucrase into the medium. The strain actively transported sucrose by a sucrose-inducible, Na+-independent process. A 10.4-kilobase DNA fragment of V. alginolyticus DNA was cloned into Escherichia coli. The recombinant E. coli(pVS100) could utilize sucrose as a sole carbon source. In contrast to V. alginolyticus, the recombinant E. coli produced both intra- and extracellular sucrase activities. Up to 20% of the total sucrase activity was in the supernatant. Sucrase synthesis in E. coli(pVS100) was inducible and was subject to glucose repression, which was relieved by cyclic AMP. Sucrose was actively transported by a sucrose-inducible, Na+-independent system in E. coli(pVS100). Sucrose uptake was inhibited by the addition of a proton conductor. The maximum velocity and apparent Km values of sucrose uptake for the V. alginolyticus strain and E. coli(pVS100) were 130 nmol/mg of protein per min and 50 microM and 6 nmol/mg of protein per min and 275 microM, respectively.
从盐渍兽皮中分离出的一株耐盐溶胶原性溶藻弧菌具有细胞内蔗糖酶活性，且不向培养基中分泌蔗糖酶。该菌株通过蔗糖诱导的、不依赖钠离子的过程主动转运蔗糖。将溶藻弧菌的一个10.4千碱基的DNA片段克隆到大肠杆菌中。重组大肠杆菌（pVS100）能够利用蔗糖作为唯一碳源。与溶藻弧菌不同，重组大肠杆菌同时产生细胞内和细胞外蔗糖酶活性。总蔗糖酶活性中高达20%存在于上清液中。大肠杆菌（pVS100）中的蔗糖酶合成是可诱导的，且受到葡萄糖阻遏，环磷酸腺苷可解除这种阻遏。在大肠杆菌（pVS100）中，蔗糖通过蔗糖诱导的、不依赖钠离子的系统主动转运。添加质子导体可抑制蔗糖摄取。溶藻弧菌菌株和大肠杆菌（pVS100）摄取蔗糖的最大速度和表观米氏常数分别为每分钟每毫克蛋白质130纳摩尔和50微摩尔以及每分钟每毫克蛋白质6纳摩尔和275微摩尔。
