半导体矿物介导非光合微生物利用光电子新途径  

The utilization of solar energy by non-phototrophic microorganisms through semiconducting minerals

作　　者：鲁安怀[1] 李艳[1] 王鑫[1] 丁竑瑞[1] 曾翠平[1] 郝瑞霞[1] 王长秋[1] 

机构地区：[1]北京大学地球与空间科学学院,北京100871

出　　处：《微生物学通报》2013年第1期190-202,共13页Microbiology China

基　　金：国家973计划项目(No.2007CB815602);国家自然科学基金重点项目(No.41230103);国家自然科学基金面上项目(No.41272003)

摘　　要：自然界中微生物按其能量代谢途径主要分为两种:光能营养微生物和化能营养微生物。化能营养微生物作为非光能营养微生物长期被排除在以日光为能量来源的能量利用途径之外。本文介绍了一种新的微生物能量利用途径,即非光能营养微生物通过半导体矿物光催化作用来利用太阳能进行生长。实验室模拟体系中,金属氧化物、金属硫化物等天然半导体矿物在模拟日光激发下产生的光电子促进了化能自养与异养微生物的生长。研究结果表明微生物的生长与光子能量和光子数量密切相关,同时不同波长光辐照下的微生物生长情况与矿物的光吸收谱相吻合。这一能量利用途径的光能-生物能转化效率为0.13‰1.90‰。在含有天然半导体矿物与天然微生物的红壤体系中,进一步发现半导体矿物光催化能够明显改变环境微生物的种群结构。已有的研究揭示了一种新发现并极有可能长期在地球上存在的微生物能量利用途径,即通过自然界中半导体矿物日光催化作用产生的光电子能够促进非光能营养微生物的生长代谢活动。Phototropy and chemotrophy microorganisms compose the whole microbe world. As non-phototrophic microorganisms are excluded from phototrophy due to the lack of photo- tropic system. Here we introduce a novel pathway of microorganism energy utilization. The non-phototrophic microorganisms could get solar energy through semiconducting mineral photocatalysis. In simulated system, under simulated solar light semiconducting minerals, such as metal oxides and metal sulfides, generated photo electrons which could be used by non-phototrophic microorganisms to support their metabolisms. The growth of microorganism was closely related to photon quantity and energy and the microorganism growth and mineral light absorption spectra were fitted well under different light wavelengths. The overall energy ef- ficiency from photon to biomass was 0.13%o to 1.90%0. Further studies revealed that in natural soil systems, semiconducting mineral photocatalysis could influence the microbial population. This study provided the evidence to reveal a novel but long existed pathway in which the semiconducting mineral photocatalysis could stimulate the non-phototrophic microorganism metabolisms.

关 键 词：非光合微生物 天然半导体矿物 光电子 能量利用途径 

分 类 号：Q93[生物学—微生物学]