Molecular diversity analysis of rumen methanogenic Archaea from goat in eastern China by DGGE methods using different primer pairs.

AIMS To screen a pair of primers suitable for denaturing gradient gel electrophoretic (DGGE) analysis of ruminal methanogenic Archaea and to detect the archaeal communities in the rumen of goat. METHODS AND RESULTS Nine primer pairs for 16S rDNA of methanogenic Archaea, including six for directed polymerase chain reaction (PCR) and three for nested PCR were first evaluated by PCR amplification of the total DNA from rumen fluids and bacteria. The DGGE analysis of rumen fluids was then conducted with three primer sets (344fGC/915r, 1106fGC/1378r and 519f/915rGC) of the nine pairs tested. Good separation and quality of patterns were obtained in DGGE analysis with primer pairs 1106fGC/1378r and 519f/915rGC. A total of 40 DNA fragments were excised from the DGGE gels and their sequences were determined. All fragments belonged to methanogenic Archaea while primer pair 519f/915rGC had better amplification ranges than the other two primer pairs. CONCLUSIONS The procedure of DGGE analysis with primer pair 519f/915rGC was more suitable for investigating methanogenic archaeal community in the rumen. The dominant methanogenic Archaea in the rumen of goat was Methanobrevibacter sp. and an unidentified methanogenic Archaea. SIGNIFICANCE AND IMPACT OF THE STUDY One pair of primers suitable for DGGE analysis of ruminal methanogenic Archaea was obtained and the molecular diversity of ruminal methanogenic Archaea in goat was investigated by PCR-DGGE.