Isolation and characterization of benzene-tolerant Rhodococcus opacus strains

Na Kyung-su

Kuroda Akio

Takiguchi Noboru

Ikeda Tsukasa

Ohtake Hisao

Kato Junichi

Journal of Bioscience and Bioengineering

Twenty-two benzene-utilizing bacteria were isolated from soil samples. Among them, three isolates were highly tolerant to benzene. They grew on benzene when liquid benzene was added to the basal salt medium at 10–90% (v/v). Taxonomical analysis identified the benzene-tolerant isolates as Rhodococcus opacus. One of the benzene-tolerant isolates, designated B-4, could utilize many aromatic and aliphatic hydrocarbons including benzene, toluene, styrene, xylene, ethylbenzene, propylbenzene, n-octane and n-decane as sole sources of carbon and energy. Strain B-4 grew well in the presence of 10% (v/v) organic solvents that it was capable of using as growth substrates. Genetic analysis revealed the benzene dioxygenase pathway is involved in benzene catabolism in strain B-4. A deletion-insertion mutant defective in the benzene dioxygenase large and small subunits genes (bnzA1 and bnzA2) was as tolerant to organic solvents as the wild-type strain B-4, suggesting that utilization or degradation of organic solvents is not essential for the organic solvent tolerance of R. opacus B-4.

solvent-tolerant bacterium

rhodococcus opacus

benzene-oxidizing bacterium

two-phase system

benzene dioxygenase gene mutation

Biology [ 460 ]

eng

日本生物工学会

Copyright (c) 2005 The Society for Biotechnology, Japan

[ISSN] 1389-1723

[NCID] AA11307678

[DOI] 10.1263/jbb.99.378

[PMID] 16233805

[DOI] http://dx.doi.org/10.1263/jbb.99.378 isVersionOf