Mendz G L, Hazell S L, Burns B P
School of Biochemistry and Molecular Genetics, University of New South Wales, Kensington, Australia.
J Gen Microbiol. 1993 Dec;139(12):3023-8. doi: 10.1099/00221287-139-12-3023.
The transport and incorporation of D-glucose into the human pathogen Helicobacter pylori was investigated employing radioactive tracer analysis and 1H and 13C nuclear magnetic resonance spectroscopy. The bacterium was found to utilize D-glucose contrary to the accepted view that it cannot catabolize carbohydrates. Under the experimental conditions employed, the rate of transport of [14C]glucose was 3.24 mmol min-1 (g protein)-1, and the rate of incorporation into the cellular mass was 1.06 mumol h-1 (g protein)-1. The utilization of [13C]glucose showed biphasic characteristics with a slower initial period followed by a phase with a rate of utilization at least an order of magnitude faster. The apparent rates of decline of glucose levels during both phases varied between strains and depended on the growth conditions of the bacteria prior to harvesting. The main product of glucose catabolism was identified as lactate. These findings provide new perspectives into the physiology of H. pylori and have implications for the active search to develop appropriate therapies for the micro-organism.
采用放射性示踪分析以及氢-1和碳-13核磁共振光谱法,对D-葡萄糖在人类病原体幽门螺杆菌中的转运及掺入情况进行了研究。结果发现,该细菌能够利用D-葡萄糖,这与普遍认为它无法分解代谢碳水化合物的观点相悖。在所采用的实验条件下,[14C]葡萄糖的转运速率为3.24 mmol·min-1·(g蛋白质)-1,掺入细胞物质的速率为1.06 μmol·h-1·(g蛋白质)-1。[13C]葡萄糖的利用呈现双相特征,初期较慢,随后是一个利用速率至少快一个数量级的阶段。两个阶段葡萄糖水平的表观下降速率因菌株而异,并取决于收获前细菌的生长条件。葡萄糖分解代谢的主要产物被鉴定为乳酸。这些发现为幽门螺杆菌的生理学提供了新的视角,并对积极寻找针对该微生物的合适治疗方法具有启示意义。