{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T05:09:56Z","timestamp":1768280996451,"version":"3.49.0"},"reference-count":41,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,12,7]],"date-time":"2021-12-07T00:00:00Z","timestamp":1638835200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001321","name":"National Research Foundation","doi-asserted-by":"publisher","award":["64788"],"award-info":[{"award-number":["64788"]}],"id":[{"id":"10.13039\/501100001321","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Glutathione transferases (GSTs) are the main detoxification enzymes in schistosomes. These parasitic enzymes tend to be upregulated during drug treatment, with Schistosoma haematobium being one of the species that mainly affect humans. There is a lack of complete sequence information on the closely related bovis and haematobium 26-kDa GST isoforms in any database. Consequently, we engineered a pseudo-26-kDa S. bovis\/haematobium GST (Sbh26GST) to understand structure\u2013function relations and ligandin activity towards selected potential ligands. Sbh26GST was overexpressed in Escherichia coli as an MBP-fusion protein, purified to homogeneity and catalyzed 1-chloro-2,4-dinitrobenzene-glutathione (CDNB-GSH) conjugation activity, with a specific activity of 13 \u03bcmol\/min\/mg. This activity decreased by ~95% in the presence of bromosulfophthalein (BSP), which showed an IC50 of 27 \u00b5M. Additionally, enzyme kinetics revealed that BSP acts as a non-competitive inhibitor relative to GSH. Spectroscopic studies affirmed that Sbh26GST adopts the canonical GST structure, which is predominantly \u03b1-helical. Further extrinsic 8-anilino-1-naphthalenesulfonate (ANS) spectroscopy illustrated that BSP, praziquantel (PZQ), and artemisinin (ART) might preferentially bind at the dimer interface or in proximity to the hydrophobic substrate-binding site of the enzyme. The Sbh26GST-BSP interaction is both enthalpically and entropically driven, with a stoichiometry of one BSP molecule per Sbh26GST dimer. Enzyme stability appeared enhanced in the presence of BSP and GSH. Induced fit ligand docking affirmed the spectroscopic, thermodynamic, and molecular modelling results. In conclusion, BSP is a potent inhibitor of Sbh26GST and could potentially be rationalized as a treatment for schistosomiasis.<\/jats:p>","DOI":"10.3390\/biom11121844","type":"journal-article","created":{"date-parts":[[2021,12,7]],"date-time":"2021-12-07T20:23:21Z","timestamp":1638908601000},"page":"1844","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Engineering a Pseudo-26-kDa Schistosoma Glutathione Transferase from bovis\/haematobium for Structure, Kinetics, and Ligandin Studies"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2749-5635","authenticated-orcid":false,"given":"Neo","family":"Padi","sequence":"first","affiliation":[{"name":"Protein Structure-Function and Research Unit, School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Braamfontein, Johannesburg 2050, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8713-2799","authenticated-orcid":false,"given":"Blessing Oluebube","family":"Akumadu","sequence":"additional","affiliation":[{"name":"Protein Structure-Function and Research Unit, School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Braamfontein, Johannesburg 2050, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Olga","family":"Faerch","sequence":"additional","affiliation":[{"name":"Protein Structure-Function and Research Unit, School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Braamfontein, Johannesburg 2050, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chinyere","family":"Aloke","sequence":"additional","affiliation":[{"name":"Protein Structure-Function and Research Unit, School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Braamfontein, Johannesburg 2050, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1171-8195","authenticated-orcid":false,"given":"Vanessa","family":"Meyer","sequence":"additional","affiliation":[{"name":"Functional Genomics and Immunogenetics Laboratory, School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Braamfontein, Johannesburg 2050, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ikechukwu","family":"Achilonu","sequence":"additional","affiliation":[{"name":"Protein Structure-Function and Research Unit, School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Braamfontein, Johannesburg 2050, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Sangweme, D.T., Midzi, N., Zinyowera-Mutapuri, S., Mduluza, T., Diener-West, M., and Kumar, N. 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