Details

Autor(en) / Beteiligte

• Dao, Anh T.N.
• Smits, Miriam
• Dang, Ha T.C.
• Brouwer, Abraham
• de Boer, Tjalf E.

Titel

Elucidating fungal Rigidoporus species FMD21 lignin-modifying enzyme genes and 2,3,7,8-tetrachlorodibenzo-p-dioxin degradation by laccase isozymes

Ist Teil von

• Enzyme and microbial technology, 2021-06, Vol.147, p.109800-109800, Article 109800

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2021

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• •The lignin modifying enzyme genes of Rigidoporus sp. FMD21 belong to three groups: laccase, manganese peroxidase and versatile peroxidase.•The more chlorine halogenation of the dibenzodioxin backbone, the lower binding affinity between dioxin and laccases.•ABTS displayed two-stage oxidation by heterologously expressed laccases which differed from natural FMD21 laccases.•2,3,7,8-tetrachlorodibenzo-p-dioxin was degraded by 50 % by three out of five tested FMD21 natural laccase isozymes. White-rot fungus Rigidoporus sp. FMD21 is a lignin-modifying enzyme producing fungus that can degrade dioxin. Extracellular enzymes from FMD21 include laccase and manganese peroxidase which are promising enzymes for myco-remediation because of their wide substrate specificity and mild catalysis conditions. The FMD21 genome was sequenced using Ion Torrent technology and consists of 38.98 Mbps with a GC content of 47.4 %. Gene prediction using Augustus with Basidiomycota reference setting resulted in 8245 genes. Functional gene annotations were carried out by using several programs and databases. We focused on laccase and ligninolytic peroxidase genes, which are most likely involved in the degradation of aromatic pollutants. The genome of FMD21 contains 12 predicted laccase genes (10 out of 12 predicted as full length) and 13 putative ligninolytic peroxidases which were annotated as MnP or versatile peroxidases. Four predicted laccases showed a higher than 65 % binding chance to 2,3,7,8-TCDD with the highest at 72 % in in silico docking analysis. Heterologous expressed laccases showed activity towards three tested substrates included ABTS, guaiacol and 2,6-DMP. ABTS displayed two-stage oxidation which differed from natural FMD21 laccases. 2,3,7,8-TCDD was degraded by 50 % after two weeks of enzymatic treatment by three out of five laccase isozymes which were natural laccases secreted by FMD21. In this study, we provide direct evidence for the 2,3,7,8-TCDD biodegradation capability of fungal laccases.