Desulfurization of thianthrene by a Gordonia sp. IITR100

Thianthrene (TA) was desulfurized by an isolated strain, Gordonia sp. IITR100. The reaction is accompanied with the formation of TA-sulfoxide, TA-sulfone and 2-phenylsulfanylphenol. The formed 2-phenylsulfanylphenol undergoes further oxidation to o-hydroxyphenyl phenylsulfone that accumulates as an end product. Metabolism of TA to TA-sulfone can also occur by E. coli-DszC i.e. E. coli cells that were harboring the gene coding for the enzyme dibenzothiophene desulfurase C. When presented to E. coli-DszC in a binary combination with dibenzothiophene, TA metabolism was completely inhibited. Metabolism of TA–TA-sulfone by E. coli-DszC, as well as the nature of metabolites formed by IITR100, suggests that the desulfurization pathway for TA is similar to that of the thiophenic compounds. This is first report on the desulfurization of thianthrene, and has implications on biodesulfurization when multiple sulfur compounds are present together.