| dc.description.abstract | Methanotrophic bacteria are methane oxidizing bacteria. Some methanotrophs able of fix nitrogen using nitrogenase enzyme. Nitrogenase is composed of two multisubunit metallo protein. Component I contains the active site to nitrogen reduction, encoded by the nifD and nifK genes. Methanotrophic isolates of BGM 3 and BGM 9 had high ammonium accumulation cultured in Nitrate Mineral Salts (NMS) free nitrogen medium. nifD gene fragmens from BGM 3 and BGM 9 were amplified and sequenced. Sequences analyzed using bioinformatics tools such as Blast-N, Blast-X, Expasy Translate Tools, Conserved Domain (CDD) and Scan PROSITE. Phylogenetic construction made using MEGA 4 software. Sequence analysis showed that the nifD sequences of BGM 3 and BGM 9 most closely related to nifD fragmen of Xanthobacter autotropicus PY2. The Identity values of nifD sequences was 92% and 91% respectively. nifD genes from these isolates encode FeMo protein, which was 4Fe4S and 2Fe2S clusters. The nifD gene of BGM 3 and BGM 9 suspected to have same ancestor with the nifD gene of Xanthobacter autotropicus PY2 and Bradyhizobium japonicum USDA 110. | en |
