{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T07:26:36Z","timestamp":1789802796173,"version":"4.0.1"},"reference-count":41,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,8,7]],"date-time":"2025-08-07T00:00:00Z","timestamp":1754524800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["2211060"],"award-info":[{"award-number":["2211060"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["GR012320 GA11562-166761-101"],"award-info":[{"award-number":["GR012320 GA11562-166761-101"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Hydrophobins are small, surface-active protein biosurfactants secreted by filamentous fungi with potential applications in industries such as pharmaceuticals, sanitation, and biomaterials. Additionally, hydrophobins are known to stabilize enzymatic processing of biomass for improved catalytic efficiency. In this study, Pichia pastoris was used to recombinantly express hydrophobin HFBI from Trichoderma reesei, a well-characterized fungal system used industrially for bioethanol production. Iterative optimization was performed on both the induction and purification of HFBI, ultimately producing yields of 86.6 mg\/L HFBI and elution concentrations of 48 \u03bcM HFBI determined pure by SDS-PAGE, over a five-day methanol-fed batch shake flask induction regiment followed by a single unit operation multimodal cation exchange purification. This final purified material represents an improvement over prior approaches to enable a wider range of potential applications for biosurfactants.<\/jats:p>","DOI":"10.3390\/microorganisms13081845","type":"journal-article","created":{"date-parts":[[2025,8,8]],"date-time":"2025-08-08T08:09:35Z","timestamp":1754640575000},"page":"1845","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Optimizing Scaled up Production and Purification of Recombinant Hydrophobin HFBI in Pichia pastoris"],"prefix":"10.3390","volume":"13","author":[{"given":"Mason A.","family":"Kinkeade","sequence":"first","affiliation":[{"name":"Department of Chemical Engineering, University of Virginia, Charlottesville, VA 22903, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aurora L.","family":"Pagan","sequence":"additional","affiliation":[{"name":"Germanna Community College, Fredericksburg, VA 22408, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6135-8677","authenticated-orcid":false,"given":"Bryan W.","family":"Berger","sequence":"additional","affiliation":[{"name":"Germanna Community College, Fredericksburg, VA 22408, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Berger, B.W., and Sallada, N.D. 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