Metabolic cooperation of Gordonia sp. strain MTCC 4818 and Arthrobacter sp. strain WY in the utilization of butyl benzyl phthalate: effect of a novel co-culture in the degradation of a mixture of phthalates

Degradation of butyl benzyl phthalate (BBP) by a co-culture of Gordonia sp. strain MTCC 4818 and Arthrobacter sp, strain WY was investigated. In the degradation of BBP by the co-culture, the limitations of the individual species in metabolizing BBP were overcome, leading to the development of a consortium capable of complete utilization of this ester. In the degradation of BBP by the co-culture, the presence of multiple esterases was demonstrated in both species by activity staining of non-denaturing gels, indicating their roles in the degradation process. The esterases were found to be inducible, with unique or broad substrate specificities towards BRP and its monoesters. Moreover, a number of catabolic enzymes other than esterases identified in the metabolism of BBP-degraded intermediates facilitated the co-culture-mediated degradation process. The versatility of the co-culture was further established by the rapid and complete degradation of a mixture of phthalate esters of environmental concern.