The degradation of alkylphenols by Sphingomonas sp. strain TTNP3 – a review on seven years of research

Over the past seven years, we have been working with Sphingomonas sp. strain TTNP3, a bacterium capable of growing on numerous alkylphenolic compounds as a source of carbon and energy. We succeeded in elucidating an unusual pathway involving an attack at the quaternary alpha-carbon atom of the substrate, a position previously thought to be highly resistant to biodegradation. Combining analytical and bioanalytical methods, a good understanding of the reaction mechanisms, the enzymes catalysing them and the organization of the genes encoding them could be gained. First studies on the use of Sphingomonas sp. strain TTNP3 in wastewater treatment have been performed revealing promising results.

► Sphingomonas sp. strain TTNP3 degrades various alkylphenols via a type II ipso-substitution mechanism.
► The downstream degradation pathway is catalysed by enzymes encoded by a gene cluster unlike those found until now in sphingomonad strains.
► It could be shown that biological wastewater treatment can be enhanced applying the strain in a membrane bioreactor.