Identification and in silico characterization of a thermophilic GH10 xylanase from hot spring metagenomes

This study sought to identify xylanases by mining metagenomic reads from high-temperature environments across multiple geographic regions. It also aimed to conduct an in-silico characterization of a promising thermophilic GH10 xylanase, analyzing its sequence, structural features, and dynamic properties. BLASTp results indicated that potentially thermophilic xylanases from different hot spring environments share high sequence similarity with xylanases from diverse phyla, including Cyanobacteria, Dictyoglomi, Bacteroidota, Bacillota, Pseudomonadota, and Acidobacteriota. Additionally, eighteen complete xylanase sequences with melting temperatures above 65 °C showed instability index values below 40 (ranging from 22.32 to 39.13) and aliphatic index values greater than 72 (ranging from 72.04 to 95.54). Molecular docking analysis revealed that the catalytic residues E164 and E270 of HSWMetXyn15 participated in noncovalent interactions within the HSWMetXyn15-X₇ docked complex. Molecular dynamics simulations indicated stable behavior of both HSWMetXyn15 and the HSWMetXyn15-X₇ complex. Structural analysis confirmed that HSWMetXyn15 belongs to the GH10 family and differs from the reference xylanase XynAS9 in several secondary structural elements. Moreover, P77 and E78 may contribute to the thermal stability of HSWMetXyn15 through their involvement in local noncovalent interactions. Therefore, the favorable structural and dynamic properties of HSWMetXyn15 compared with the reference xylanase XynAS9 highlight its potential as a promising candidate for high-temperature industrial applications, including biofuel production, animal feed processing, paper and pulp manufacturing, and food processing.