Is the Amino Acid HIS458 and ASP/ASN206 of Laccase from 𝑇. 𝑉𝑒𝑟𝑠𝑖𝑐𝑜𝑙𝑜𝑟 and 𝑇. 𝐻𝑖𝑟𝑠𝑢𝑡𝑎 Crucial for the Decolorization of Polycyclic Aromatic Textile Dyes? An 𝐼𝑛 𝑆𝑖𝑙𝑖𝑐𝑜 Investigation

The development of the textile industry produced a vast array of dye variations. Textile dyes are widely used, easily synthesized, chemically stable, and poisonous. The most harmful category of synthetic dyes, which are also frequently found in wastewater as hazardous industrial pollutants, are highly mutagenic and carcinogenic to both people and animals, which highlights the necessity of decolorization. In this study, eleven polycyclic aromatic textile dyes- Acid Blue 225, Disperse Blue 3, Reactive Blue 19, Acid Blue 74, Basic Red 9, Direct Blue 71, Acid Red 27, Acid Orange 52, Acid Orange 6, Reactive Blue 221, and Reactive Black 5 of Azo, Anthraquinone, Indigoid, and Rosaniline molecular class which were previously identified as potential target for laccase of T. Versicolor and T. Hirsuta was reinvestigated to identify the amino acids that are crucial for bond formation. Biovia Discovery studio and DoGSiteScorer online tool were used to identify active site residues, and AutoDockVina to calculate docking scores. Among eleven dyes, Direct blue 71, Acid red 27, Acid blue 225, and Reactive blue 19 were found to be more prone to bond formation with the laccase of T. Versicolor with binding affinities -8.1, -7.4, -7.2, and -7.2 kcal/mol, and T. Hirsuta with -8.1, -8.5, -7.9, and -7.5 kcal/mol compared to other dyes. From the structural analysis, HIS458 of both laccases was found to be crucial for efficient electron transfer.

Is the Amino Acid HIS458 and ASP/ASN206 of Laccase from 𝑇. 𝑉𝑒𝑟𝑠𝑖𝑐𝑜𝑙𝑜𝑟 and 𝑇. 𝐻𝑖𝑟𝑠𝑢𝑡𝑎 Crucial for the Decolorization of Polycyclic Aromatic Textile Dyes? An 𝐼𝑛 𝑆𝑖𝑙𝑖𝑐𝑜 Investigation Keywords:

Laccase , Decolorization , Molecular docking analysis , T. Versicolor , T. Hirsuta , Loop region 1-4 , HIS458