African Journal of Biotechnology Vol. 4 (7), pp. 639-645, July 2005          
ISSN 1684–5315 � 2005 Academic Journals

Full Length Research Paper

Rhodococcus opacus strain RW, a resorcinol-degrading bacterium from the gut of Macrotermes michaelseni

David Kamanda Ngugi^1Y, Muniru Khamis Tsanuo² and Hamadi Iddi Boga¹*

¹Botany Department, and ²Chemistry Department, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000 (00200) Nairobi, Kenya.

*Corresponding Author E-mail: [email protected].

^YCurrent Address: Max Planck Institute for Terrestrial Microbiology, Department of Biogeochemistry, Karl-von-Frisch-Strasse, D-35043 Marburg, Germany.

Accepted 14 May, 2005

The population of resorcinol degrading bacteria in the intestinal tract of fungi-cultivating termite, Macrotermes michaelseni, was estimated to be 6.8 � 10² cells/ml. A gram-positive bacterium designated RW, capable of degrading resorcinol, was isolated from the highest positive dilution. Isolate RW could also degrade phenol and benzoic acid aerobically, and anaerobically using nitrate as an electron acceptor. The isolate is a rod-shaped bacterium that exhibited evolutionary relatedness with the genus Rhodococcus, as determined by phenotypic traits and physiological tests, and a 16S rRNA gene sequence similarity value of 99.6% to the closest Rhodococcus opacus strain. On the basis of these results isolate RW is proposed as a new strain in the species R. opacus. The ability of the isolate to degrade resorcinol, phenol and benzoic acid makes it a potential candidate for use in bioremediation of environments contaminated by such or related compounds.

Key words: Rhodococcus opacus, resorcinol, Macrotermes michaelseni, termites, bioremediation, monoaromatic compounds.