Isolation of a bacterial consortium able to degrade the fungicide thiabendazole: the key role of a Sphingomonas phylotype

Appl Microbiol Biotechnol. 2017 May;101(9):3881-3893. doi: 10.1007/s00253-017-8128-5. Epub 2017 Feb 2.


Thiabendazole (TBZ) is a fungicide used in fruit-packaging plants. Its application leads to the production of wastewaters requiring detoxification. In the absence of efficient treatment methods, biological depuration of these effluents could be a viable alternative. However, nothing is known regarding the microbial degradation of the recalcitrant and toxic to aquatics TBZ. We report the isolation, via enrichment cultures from a polluted soil, of the first bacterial consortium able to rapidly degrade TBZ and use it as a carbon source. Repeated efforts using various culture-dependent approaches failed to isolate TBZ-degrading bacteria in axenic cultures. Denaturating gradient gel electrophoresis (DGGE) and cloning showed that the consortium was composed of α-, β- and γ-Proteobacteria. Culture-independent methods including antibiotics-driven selection with DNA/RNA-DGGE, q-PCR and stable isotope probing (SIP)-DGGE identified a Sphingomonas phylotype (B13) as the key degrading member. Cross-feeding studies with structurally related chemicals showed that ring substituents of the benzimidazole moiety (thiazole or furan rings) favoured the cleavage of the imidazole moiety. LC-MS/MS analysis verified that TBZ degradation proceeds via cleavage of the imidazole moiety releasing thiazole-4-carboxamidine, which was not further transformed, and the benzoyl moiety, possibly as catechol, which was eventually consumed by the bacterial consortium as suggested by SIP-DGGE.

Keywords: Fruit-packaging industry; Pesticide biodegradation; SIP-DGGE; Sphingomonas; Thiabendazole; Wastewaters.

MeSH terms

  • Bacteria / classification*
  • Bacteria / genetics
  • Bacteria / metabolism*
  • Biotransformation
  • Carbon / metabolism
  • Chromatography, Liquid
  • Cloning, Molecular
  • Denaturing Gradient Gel Electrophoresis
  • Fungicides, Industrial / metabolism*
  • Metabolic Networks and Pathways
  • Microbial Consortia*
  • Sequence Analysis, DNA
  • Soil Microbiology
  • Tandem Mass Spectrometry
  • Thiabendazole / metabolism*


  • Fungicides, Industrial
  • Carbon
  • Thiabendazole