Methanobacterium oryzae sp. nov., a novel methanogenic rod isolated from a Philippines ricefield.

Abstract

A rod (0 3-0 4 µmi3-10 µm) to filamentous (up to 40 µm) non-motile methanogenic bacterium, designated strain FPi T (T l type strain), was isolated from ricefield soil in the Philippines. The strain uses H 2 MCO 2 or formate for growth and produces CH 4 . Optimum growth temperature is 40 SC ; no growth is observed at 15 SC or 45 SC. 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 N1 . The GMC 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 (l DSM 11106 T ).

Methanobacterium congolense sp. nov., from a methanogenic fermentation of cassava peel.

“…With its optimum growth temperature of 37-42 mC, it is clearly distinct from the thermophilic species of Methanobacterium and Methanothermobacter, which also generally have a DNA base compositions greater than 40 mol % GjC (Boone et al, 1993 ;Wasserfallen et al, 2000). Strain C T differs from the mesophilic species Methanobacterium alcaliphilum (Worakit et al, 1986), Methanobacterium espanolae (Patel et al, 1990), Methanobacterium ivanovii (Jain et al, 1987), Methanobacterium uliginosum (Ko$ nig, 1984 and Methanobacterium oryzae (Joulian et al, 2000) in its ability to utilize 2-propanol or 2-butanol as hydrogen donors for the reduction of CO # to produce methane. The optimum pH for growth of strain C T (pH 7n2) is also quite different from those of Methanobacterium alcaliphilum (pH 8n1-9n1), Methanobacterium uliginosum (pH 6n0-8n5) and Methanobacterium espanolae (pH 5n6-6n2).…”

The Paleoproterozoic snowball Earth: A climate disaster triggered by the evolution of oxygenic photosynthesis

“…Moreover, cyanobacteria cannot be identified solely by a filamentous form. Many nonoxygenic bacteria are also filamentous, including some mat-forming green nonsulfur and purple sulfur bacteria (58,59) and a methanogenic archeon (60). The wide variety of filamentous prokaryotes highlights a problem in identifying fossil microbes lacking clear evidence of cell differentiation based on morphology: Any given form has probably arisen many times in Earth history, both in extant and extinct organisms.…”

Methanogenic archaeal communities in rice roots grown in flooded soil pots: Estimation by PCR-DGGE and sequence analyses

“…etc. had been isolated or identified by sequence analysis of environmental DNA from rice field soils (Asakawa et al 1993;Asakawa and Hayano 1995;Kudo et al 1997;GroBkopf et al 1998a;Joulian et al 1998Joulian et al , 2000Chin et al 1999a, b;Dianou et al 200 1;Mizukami et al 2001). In contrast, infOlmation about their communities in rice roots is limited at present.…”