Role of heterotrophic bacteria in complete mineralization of trichloroethylene by Methylocystis sp. strain M.
Biodegradation experiments with radioactively labeled trichloroethylene showed that 32% of the radioactive carbon was converted to glyoxylic acid, dichloroacetic acid and trichloroacetic acid and that the same percentage was converted to CO2 and CO after 140 h of incubation by a pure culture of a type II methane-utilizing bacterium, Methylocystis sp. strain M, isolated from a mixed culture, MU-81, in our laboratory. In contrast, these water-soluble (14C)trichloroethylene degradation products were completely or partially degraded further and converted to CO2 by the MU-81 mixed culture. This phenomenon was attributed to the presence of a heterotrophic bacterium (strain DA4), which was identified as Xanthobacter autotrophicus, in the MU-81 culture. The results indicate that the heterotrophic bacteria play an important role in complete trichloroethylene degradation by methanotrophs.
Uchiyama
H
H
National Institute for Environmental Studies, Onogawa, Japan.
Nakajima
T
T
Yagi
O
O
Nakahara
T
T
D001673:Biodegradation, Environmental; D002250:Carbon Radioisotopes; D008772:Methylococcaceae / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D008903:Minerals / Q000378:metabolism*; D014241:Trichloroethylene / Q000378:metabolism*
D002250:Carbon Radioisotopes; D008903:Minerals; D014241:Trichloroethylene