{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T01:40:50Z","timestamp":1780623650630,"version":"3.54.1"},"reference-count":45,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,3,28]],"date-time":"2025-03-28T00:00:00Z","timestamp":1743120000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Scientific and Technological Project of Henan Province","award":["232102320330"],"award-info":[{"award-number":["232102320330"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The enzymatic hydrolysis of lignocellulose is often hindered by the glucose-mediated inhibition of \u03b2-glucosidases, a major bottleneck in industrial cellulose degradation. Identifying novel glucose-tolerant \u03b2-glucosidases is essential for enhancing saccharification efficiency. In this study, we cloned and heterologously expressed a novel \u03b2-glucosidase, RpBgl8, from the termite Reticulitermes perilucifugus in Escherichia coli. Sequence and structural analyses classified RpBgl8 as a glycoside hydrolase family 1 enzyme. The purified enzyme exhibited optimal activity at 45 \u00b0C and pH 7.0, with broad stability across pH 4.0\u20138.0. Notably, RpBgl8 demonstrated high tolerance to lignocellulose-derived inhibitors and organic solvents, maintaining 100% activity in 15% ethanol. Furthermore, RpBgl8 exhibited outstanding glucose tolerance, retaining 100% activity at 2.5 M glucose and 82% activity at 4.0 M glucose\u2014outperforming most previously reported \u03b2-glucosidases. A structural analysis revealed a narrow, hydrophobic substrate pocket, with residue F124 at the glycone-binding site critical for minimizing glucose accumulation. The F124W mutation significantly reduced glucose tolerance, confirming that hydrophobic interactions at the active site mitigate inhibition. These findings establish RpBgl8 as a promising candidate for high-solid biomass processing and simultaneous saccharification and fermentation applications, highlighting termites as underexplored sources of biocatalysts with unique industrial potential.<\/jats:p>","DOI":"10.3390\/ijms26073118","type":"journal-article","created":{"date-parts":[[2025,3,28]],"date-time":"2025-03-28T06:06:35Z","timestamp":1743141995000},"page":"3118","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Biochemical and Structural Characterization of a Highly Glucose-Tolerant \u03b2-Glucosidase from the Termite Reticulitermes perilucifugus"],"prefix":"10.3390","volume":"26","author":[{"given":"Guotao","family":"Mao","sequence":"first","affiliation":[{"name":"College of Life Sciences, Henan Agricultural University, Zhengzhou 450046, China"},{"name":"The Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture and Rural Affairs, Henan Agricultural University, Zhengzhou 450046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ming","family":"Song","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Henan Agricultural University, Zhengzhou 450046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hao","family":"Li","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Henan Agricultural University, Zhengzhou 450046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junhan","family":"Lin","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Henan Agricultural University, Zhengzhou 450046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kai","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Henan Agricultural University, Zhengzhou 450046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qian","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Henan Agricultural University, Zhengzhou 450046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zengping","family":"Su","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Henan Agricultural University, Zhengzhou 450046, China"},{"name":"The Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture and Rural Affairs, Henan Agricultural University, Zhengzhou 450046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9733-0836","authenticated-orcid":false,"given":"Hongsen","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Henan Agricultural University, Zhengzhou 450046, China"},{"name":"The Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture and Rural Affairs, Henan Agricultural University, Zhengzhou 450046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lijuan","family":"Su","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Henan Agricultural University, Zhengzhou 450046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hui","family":"Xie","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Henan Agricultural University, Zhengzhou 450046, China"},{"name":"The Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture and Rural Affairs, Henan Agricultural University, Zhengzhou 450046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andong","family":"Song","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Henan Agricultural University, Zhengzhou 450046, China"},{"name":"The Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture and Rural Affairs, Henan Agricultural University, Zhengzhou 450046, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Mankar, A.R., Pandey, A., Modak, A., and Pant, K.K. 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