title: Phylogenetic diversity of nitrogen fixation genes in the intestinal tract of Reticulitermes chinensis Snyder.
abstract: Wood-feeding termites live on cellulolytic materials that typically lack of nitrogen sources. It was reported that symbiotic microbes play important roles in the maintenance of a normal nitrogen contents in termite by different metabolisms including nitrogen fixation. In this study, the diversity of nitrogen-fixing organisms in the symbiotic intestinal microflora of Reticulitermes                 chinensis Snyder was investigated with culture independent method. Fragments of the nifH genes, which encode dinitrogenase reductase, were directly amplified from the DNA of the mixed microbial population in the termite gut with four sets of primers corresponding to the conserved regions of the genes. Clones were randomly selected and analyzed by RFLP. Sequence analysis revealed that a large number of nifH sequences retrieved from the termite gut were most closely related to strict anaerobic bacteria such as clostridia and spirochetes, some of the others were affiliated with proteobacteria, bacteroides, or methanogenic archaea. The results showed that there was a remarkable diversity of nitrogenase genes in the gut of Reticulitermes                 chinensis Snyder.
authors.affiliation: Hubei Key Laboratory of Genetic Regulation and Integrative Biology, College of Life Sciences, Central China Normal University, 152 Luoyu Avenue, Wuhan, People's Republic of China.
authors.forename: Xin
authors.initials: X
authors.lastname: Du
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Li
authors.forename: Yin
authors.initials: Y
authors.lastname: Wang
authors.forename: Jianxin
authors.initials: J
authors.lastname: Peng
authors.forename: Huazhu
authors.initials: H
authors.lastname: Hong
authors.forename: Hong
authors.initials: H
authors.lastname: Yang
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D044822:Biodiversity; D007422:Intestines / Q000382:microbiology*; D020049:Isoptera / Q000382:microbiology*; D008969:Molecular Sequence Data; D009586:Nitrogen Fixation; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D013559:Symbiosis
chemical_list: D001426:Bacterial Proteins; D010088:Oxidoreductases; C029130:nitrogenase reductase