Obligate methylotrophy: evaluation of methyl formate as a C1 compound

Methyl formate, a C1 compound reportedly utilized by obligate methylotrophs, gave growth for Methylococcus capsulatus (Texas) but not for Methylosinus trichosporium (OB3b). Both organisms grew on methane, but only M. capsulatus (Texas) utilized methanol; neither organism could use formate as the sole carbon–energy source. Studies with M. capsulatus (Texas) showed that its growth rate on methyl formate was much slower than on methane or methanol, regardless of whether the cells were methane, methanol, or methyl formate grown. Methyl formate underwent "spontaneous" hydrolysis in uninoculated growth medium to yield formic acid and methanol, the latter serving as the actual growth substrate for M. capsulatus (Texas).