Parvibaculum lavamentivorans converts linear alkylbenzenesulphonate surfactant to sulphophenylcarboxylates, α,β-unsaturated sulphophenylcarboxylates and sulphophenyldicarboxylates, which are degraded in communities

摘要

Aims: The aims were to test whether Parvibaculum lavamentivorans~T degraded commercial linear alkylbenzenesulphonate (LAS) surfactant via ω-oxygenation and β-oxidation to sulphophenylcarboxylates (SPCs), whether the organism was widespread and reisolable, and whether the degradative community used the 4-sulphocatechol 1,2-dioxygenase to cleave the aromatic ring from LAS. Methods and Results: Heterotrophic P. lavamentivorans~T converted LAS (side chain length C_(10)-C_(13)) to SPCs (C_4-C_(13)), α,β-unsaturated SPCs (C_4-C_(13)) and sulphophenyldicarboxylates (SPdCs) (at least C_8-C_(12)). Identifications came from high performance liquid chromatography (HPLC) separation, an electrospray interface and mass spectrometry. No evidence for other paths was found. The degradation of LAS in trickling filters inoculated with environmental samples always showed transient SPC intermediates (HPLC) and the presence of the P. lavamentivorans morphotype in the community. One new isolate was obtained. A community able to mineralize LAS contained 4-sulphocatechol-1,2-dioxygenase at high specific activity. Conclusions: Parvibaculum lavamentivorans~T degrades commercial LAS via ω-oxygenation, oxidation and chain shortening through β-oxidation to yield a wide range of SPCs. The latter are degraded in bacterial communities which contain organisms like P. lavamentivorans, and which utilize sulphocatechol dioxygenase for ring cleavage. Significance and Impact of the Study: There is one widespread pathway to degrade LAS. Any traces of LAS and larger amounts of SPCs in the effluent from sewage works are exposed to degradative organisms in acclimated and pristine environments. These degradative reactions can now be studied in pure cultures.