Wylie J L, Worobec E A
Department of Microbiology, University of Manitoba, Winnipeg, Canada.
J Bacteriol. 1995 Jun;177(11):3021-6. doi: 10.1128/jb.177.11.3021-3026.1995.
Using interposon mutagenesis, we have generated strains of Pseudomonas aeruginosa which lack or overexpress the substrate-selective OprB porin of this species. A marked decrease or increase in the initial uptake of glucose by these strains verified the role of OprB in facilitating the diffusion of glucose across the outer membrane of P. aeruginosa. However, we also demonstrated that the loss or overexpression of OprB had a similar effect on the uptake of three other sugars able to support the growth of this bacterium (mannitol, glycerol, and fructose). This effect was restricted to carbohydrate transport; arginine uptake was identical in mutant and wild-type strains. These results indicated that OprB cannot be considered strictly a glucose-selective porin; rather, it acts as a central component of carbohydrate transport and is more accurately described as a carbohydrate-selective porin.
利用转座子诱变技术，我们构建了铜绿假单胞菌菌株，这些菌株缺失或过表达该菌种的底物选择性孔蛋白OprB。这些菌株对葡萄糖的初始摄取量显著减少或增加，证实了OprB在促进葡萄糖跨铜绿假单胞菌外膜扩散中的作用。然而，我们还证明，OprB的缺失或过表达对其他三种能够支持该细菌生长的糖类（甘露醇、甘油和果糖）的摄取具有类似影响。这种影响仅限于碳水化合物运输；突变株和野生型菌株对精氨酸的摄取是相同的。这些结果表明，不能严格地将OprB视为葡萄糖选择性孔蛋白；相反，它是碳水化合物运输的核心组成部分，更准确地说应被描述为碳水化合物选择性孔蛋白。
