Primary Studies On The Symbiotic Archaea In The Gut Of Wood-feeding Lower Termites Reticulitermes Chinensis

The gut of wood-feeding lower termite harbors a remarkable density and diversity of symbiotic flagellates,bacteria and archaea, which play important roles in the cellulose digestion of the host. The symbiotic archaea in the gut of wood-feeding lower termite, Reticulitermes chinensis Snyder, was observed in situ by the NIKON UV epifluorescence microscopy (F420). The phylogeny of the symbiotic archaea of Reticulitermes chinensis Snyder was examined by a strategy that does not rely on cultivation of the resident microorganisms. The results are reported as follows:1.There are lots of F420 autofluorescent cells on the luminal surfaceof hindgut (paunch region) epithelium of Reticulitermes chinensis Snyder.The main morphology of methanogens on the hindgut epithelium were short rods,the rest of them were long curved rods.2.The r phylogenetic diversity of the symbiontic methanogensinhabiting the gut of Reticulitermes chinensis Snyder was analyzed without cultivation. Small Subunit ribosomal RNA (ssr RNA) genes were directly amplified from the DNA extraction of the termite gut by polymerase chain reaction (PCR) using archaeal specific primers. PCR products were ligated into the T-easy vector (Promega),and transformed to E.coli DH5αcells.Randomly picked clones were checked for their insert size by vector-targeted PCR. The restriction fragment length polymorphism analysis was performed using Msp I restriction enzyme digestion.The RFLP analysis revealed the diversity of the archaeal community in the gut of Reticulitermes chinensis Snyder. Clones represent different ribotypes were sequenced. The nucleotide sequences of the 16S rDNA were compared with those of the known methanogens, and the phylogenetic tree was constructured. Phylogenetic analysis indicated that the termite symbiontic methanogens belonged to the Methanobrevibacter genus in the Methanobacteriaceae family of the order Methanobacteriales.