MICROBIAL DESULFURIZATION OF DIBENZOTHIOPHENE - A SULFUR-SPECIFIC PATHWAY

Rhodococcus rhodochrous strain IGTS8 metabolizes dibenzothiophene, a model compound for organic sulfur in fossil fuels, in a sulfur-specific manner. Two routes of desulfurization have been identified. Under growth conditions, the intermediates are dibenzothiophene sulfoxide, dibenzothiophene sulfone, 2'-hydroxybiphenyl-2-sulfonate, and 2,2'-dihydroxybiphenyl. Stationary phase cells produce 2-hydroxybiphenyl as the desulfurized product and use the 2'-hydroxybiphenyl-2-sulfinate, rather than the sulfonate, as the key intermediate.