{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T16:58:10Z","timestamp":1791910690642,"version":"4.3.4"},"reference-count":57,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2016,2,2]],"date-time":"2016-02-02T00:00:00Z","timestamp":1454371200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>Animal venom (e.g., scorpion) is a rich source of various protein and peptide toxins with diverse physio-\/pharmaco-logical activities, which generally exert their action via target-specific modulation of different ion channel functions. Scorpion venoms are among the most widely-known source of peptidyl neurotoxins used for callipering different ion channels, such as; Na+, K+, Ca+, Cl\u2212, etc. A new peptide of the chlorotoxin family (i.e., Bs-Tx7) has been isolated, sequenced and synthesized from scorpion Buthus sindicus (family Buthidae) venom. This peptide demonstrates 66% with chlorotoxin (ClTx) and 82% with CFTR channel inhibitor (GaTx1) sequence identities reported from Leiurus quinquestriatus hebraeus venom. The toxin has a molecular mass of 3821 Da and possesses four intra-chain disulphide bonds. Amino acid sequence analysis of Bs-Tx7 revealed the presence of a scissile peptide bond (i.e., Gly-Ile) for human MMP2, whose activity is increased in the case of tumour malignancy. The effect of hMMP2 on Bs-Tx7, or vice versa, observed using the FRET peptide substrate with methoxycoumarin (Mca)\/dinitrophenyl (Dnp) as fluorophore\/quencher, designed and synthesized to obtain the lowest Km value for this substrate, showed approximately a 60% increase in the activity of hMMP2 upon incubation of Bs-Tx7 with the enzyme at a micromolar concentration (4 \u00b5M), indicating the importance of this toxin in diseases associated with decreased MMP2 activity.<\/jats:p>","DOI":"10.3390\/toxins8020036","type":"journal-article","created":{"date-parts":[[2016,2,3]],"date-time":"2016-02-03T01:48:18Z","timestamp":1454464098000},"page":"36","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Structure-Activity Relationship of Chlorotoxin-Like Peptides"],"prefix":"10.3390","volume":"8","author":[{"given":"Syed","family":"Ali","sequence":"first","affiliation":[{"name":"International Center for Chemical and Biochemical Sciences (ICCBS), HEJ Research Institute of Chemistry, University of Karachi, Karachi-75270, Pakistan"},{"name":"Interfaculty Institute of Biochemistry (IIB), University of Tuebingen, Hoppe-Seyler Str. 4, Tuebingen D-72076, Germany"},{"name":"Venom Evolution Laboratory, School of Biological Sciences, University of Queensland, Brisbane, QLD 4072, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2449-4653","authenticated-orcid":false,"given":"Mehtab","family":"Alam","sequence":"additional","affiliation":[{"name":"International Center for Chemical and Biochemical Sciences (ICCBS), HEJ Research Institute of Chemistry, University of Karachi, Karachi-75270, Pakistan"},{"name":"Interfaculty Institute of Biochemistry (IIB), University of Tuebingen, Hoppe-Seyler Str. 4, Tuebingen D-72076, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Atiya","family":"Abbasi","sequence":"additional","affiliation":[{"name":"International Center for Chemical and Biochemical Sciences (ICCBS), HEJ Research Institute of Chemistry, University of Karachi, Karachi-75270, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eivind","family":"Undheim","sequence":"additional","affiliation":[{"name":"Venom Evolution Laboratory, School of Biological Sciences, University of Queensland, Brisbane, QLD 4072, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6661-1283","authenticated-orcid":false,"given":"Bryan","family":"Fry","sequence":"additional","affiliation":[{"name":"Venom Evolution Laboratory, School of Biological Sciences, University of Queensland, Brisbane, QLD 4072, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hubert","family":"Kalbacher","sequence":"additional","affiliation":[{"name":"Interfaculty Institute of Biochemistry (IIB), University of Tuebingen, Hoppe-Seyler Str. 4, Tuebingen D-72076, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wolfgang","family":"Voelter","sequence":"additional","affiliation":[{"name":"Interfaculty Institute of Biochemistry (IIB), University of Tuebingen, Hoppe-Seyler Str. 4, Tuebingen D-72076, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,2,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1016\/j.actatropica.2008.05.021","article-title":"Epidemiology of scorpionism: A global appraisal","volume":"107","author":"Chippaux","year":"2008","journal-title":"Acta Tropica"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1046\/j.1432-1327.1999.00625.x","article-title":"Scorpion toxins specific for Na+-channels","volume":"264","author":"Possani","year":"1999","journal-title":"Eur. 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