Sphingomonads involved in the biodegradation of xenobiotic polymers

Sphingomonads involved in the microbial degradation of xenobiotic polymers are introduced. The metabolism of polyethylene glycol was the primary focus of the study. Several others, including polyvinyl alcohol, polyethylene and polyaspartate were also studied. It is suggested that these xenobiotic polymers are metabolized by intracellular enzymes located in the periplasmic space or bound to membranes, indicating that transport of these polymers through outer membranes is requisite for their metabolism. Involvement of specific membrane structures of sphingomonads such as unusual sphingolipids is suggested for membrane transport of xenobiotic compounds, especially hydrophobic materials.