Distribution characteristics and diversities of cbb and coxL genes in paddy soil profiles from southern China  

作　　者：Wentao PENG Yan WANG Xiuxiu ZHU Liufeng XU Juan ZHAO Zhongli CUI Hui CAO 

机构地区：[1]College of Life Sciences/Key Laboratory of Agricultural Environmental Microbiology,Ministry of Agriculture and Rural Affairs,Nanjing Agricultural University,Nanjing 210095(China) [2]Rubber Research Institute,Chinese Academy of Tropical Agricultural Sciences,Haikou 571101(China)

出　　处：《Pedosphere》2021年第6期954-963,共10页土壤圈（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.42077026 and 41371262)。

摘　　要：The Calvin-Benson-Bassham cycle and Wood-Ljungdahl pathway are two well-known ones in the six carbon sequestration pathways,but the current knowledge of their occurrence in different layers of agricultural soil profiles is poor.In this study,the diversities of three genes encoding ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubis CO),i.e.,genes encoding the green-like(cbbLG)and red-like(cbbLR)forms of Rubis COⅠ and encoding Rubis COⅡ(cbbM),and the gene encoding carbon monoxide dehydrogenase large subunit(coxL)from five paddy soils in southern China were investigated by real-time quantitative polymerase chain reaction,restriction fragment length polymorphism(RFLP)analysis,and clone library.The abundances of the four genes ranged from 10^(7) to 10^(9) copies g^(-1) soil,and the cbbLR gene outnumbered the other three genes in all soil samples,suggesting important roles they play in carbon dioxide(CO_(2))fixation.In addition,it was found that the copy numbers of cbbLR and cbbLG decreased with increasing soil depth,while the copy numbers of cbbM and coxL decreased in the shallow depths but increased with increasing soil depth.The results of RFLP showed a larger Shannon index(H)in the deeper soil layers among the four gene clone libraries,indicating that the community diversity in these soil layers was greater.The cbbLG gene had relatively low diversity(at genus level),and most of the sequences were classified as Sideroxydans and Thiobacillus.In contrast,the highly diverse groups were found in the other three gene clone libraries(cbbLR,cbbM,and coxL),most of which were distantly related to known sequences,even forming separate clusters.In summary,this study provides a new insight into CO_(2) fixers along agricultural soil profiles by comparing four bacterial genes.

关 键 词：Calvin-Benson-Bassham cycle carbon dioxide fixation carbon monoxide dehydrogenase ribulose-1 5-bisphosphate carboxylase/oxygenase 

分 类 号：S154.3[农业科学—土壤学]