Abstract
C Joulian, BKC Patel, B Ollivier, JL Garcia and PA Roger
Laboratoire de Microbiologie IRD, Universite de Provence -- ESIL, Case 925, 163 Avenue de Luminy, 13288 Marseille cedex 9, France
A rod (0.3--0.4 microm x 3--10 microm) to filamentous (up to 40 microm) non-motile methanogenic bacterium, designated strain FPi(T) (T=type strain), was isolated from ricefield soil in the Philippines. The strain uses H(2)+CO(2) or formate for growth and produces CH(4). Optimum growth temperature is 40 degrees C; no growth is observed at 15 degrees C or 45 degrees C. Optimum pH for growth is 7; no growth is observed at pH 5.5 or 9.0. Strain FPi(T) is halotolerant and grows at NaCl concentrations of 0--25 g l(-1). The G+C content of its DNA is 31 mol%. Based on 16S rRNA gene sequence analysis, the isolate was identified as a new species of the genus Methanobacterium: Methanobacterium oryzae sp. nov. The type strain is FPi(T) (=DSM 11106(T)).