Abstract
A study was made of the incorporation of methanol and bicarbonate into the cell constituents of denitrifying or aerobic methanol grown and autotrophic H2-O2-CO2grown Hyphomicrobium sp. 53-49. Cells were incubated with [14C]methanol or [14C]bicarbonate, and the distribution of the radioactivity in the nonvolatile constituents of ethanol extracts of cells was examined. When denitrifying grown cells were incubated with [14C]methanol, the major part of the radioactivity was fixed to serine as the first stable compound. Aerobic methanol grown cells also fixed [14C]methanol mainly to serine. These results suggest that methanol grown cells assimilate methanol by the serine pathway. Whendenitrifying or aerobic methanol grown cells were incubated with [14C]bicarbonate, malate was mainly observed as a nonvolatile compound in the initial period of the incubation. Autotrophic grown cells also fixed the major part of [14C]bicarbonate to malate. In this case, phosphoglyceric acid was found in the phosphorylated compounds area.