^(13)C标记磷脂脂肪酸分析在土壤微生物生态研究中的应用  

Application of ^(13)C-labeled PLFA analysis in soil microbial ecology studies

作　　者：李增强[1,2] 赵炳梓[1] 张佳宝[1] 

机构地区：[1]中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室,南京210008 [2]中国科学院大学,北京100049

出　　处：《中国生态农业学报》2016年第4期470-477,共8页Chinese Journal of Eco-Agriculture

基　　金：国家自然科学基金项目(41271311);国家科技支撑计划项目(2012BAD05B0203);中国科学院科技服务网络计划(STS计划)项目(KFJ-SW-STS-142-3;KFJ-EW-STS-083-2;KFJ-EW-STS-055-1)资助~~

摘　　要：磷脂脂肪酸(PLFA)是微生物细胞膜的重要组成成分,不同微生物群落可通过不同生化途径合成不同的PLFA,因此可选择某些PLFA作为微生物群落结构变化的生物标志物。PLFA与稳定性同位素^(13)C标记(^(13)C-PLFA)技术结合,不仅能够确定原位土壤环境中微生物群落组成,而且能够定向发掘土壤生态系统中参与碳源代谢过程的微生物群落,提供复杂群落中土壤微生物相互作用的信息,具有广阔的应用前景。其基本原理为:将富集^(13)C稳定同位素的基质加入土壤中,土壤中的某些微生物群落利用基质^(13)C合成PLFA,提取并纯化土壤微生物的PLFA,利用气相色谱-燃烧-同位素比例质谱(GC-C-IRMS)测定其^(13)C丰度,通过对比分析,从而获取微生物群落组成与其功能的直接信息。本文在介绍了^(13)C-PLFA原理的基础上,综述了该技术在光合同化碳的根际微生物利用、土壤有机质分解的激发效应、甲烷氧化、有机污染物降解、外源简单碳源和外源复杂碳源的微生物利用等方面的应用,对此项技术的优缺点进行了分析并展望了其未来应用。Analysis of phospholipid fatty acids（PLFA） is an effective non-culture-based technique for information on living soil microbial community. PLFA is an important component of microbial cell membranes. Microbes can synthesize this special PLFA through various biochemical pathways hence some PLFA can be used as biomarker for a microbial community. When coupled with stable isotope ^（13）C-labeled（^（13）C-PLFA） technique, PLFA can be used to identify in situ structures of soil microbial communities. This can also be used to explore soil microbial functional communities responsible for metabolic processes of soil carbon sources in soil ecosystem, thus providing abundant information about microbial interactions in complex communities. This technique has the potential for wide future applications. The principle of ^（13）C-PLFA technique is as follows： 1） adding ^（13）C-rich substrates to the soils assimilated by some members of the soil microbial community; 2） extracting and purifying PLFA from soil substrate mixtures; 3） determining 13 C value of PLFA using gas chromatography combustion isotope ratio mass spectrometry（GC-C-IRMS）; and 4） deriving required information by comparative analysis. This study introduced the principle of ^（13）C-PLFA technique and reviewed the applications of ^（13）C-PLFA in the fields of photosynthetic carbon utilization by rhi-zosphere microorganisms, priming effects of soil organic matter decomposition and mineralization, microbial oxidation of methane, degradation of organic pollutants and microbial utilization of exogenous simple and complicated carbon sources. The limitations and application potentials of this technique were also discussed. It was concluded that ^（13）C-PLFA method was an excellent way of providing insight into the relations between microbial community composition and soil biogeochemical cycle.

关 键 词：磷脂脂肪酸 稳定性同位素标记技术 土壤微生物 群落结构 微生物功能 

分 类 号：S154.3[农业科学—土壤学]