{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T17:30:52Z","timestamp":1791307852290,"version":"4.3.1"},"reference-count":52,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2014,10,31]],"date-time":"2014-10-31T00:00:00Z","timestamp":1414713600000},"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>A monomeric basic PLA2 (PhTX-II) of 14149.08 Da molecular weight was purified to homogeneity from Porthidium hyoprora venom. Amino acid sequence by  in tandem mass spectrometry revealed that PhTX-II belongs to Asp49 PLA2 enzyme class and displays conserved domains as the catalytic network, Ca2+-binding loop and the hydrophobic channel of access to the catalytic site, reflected in the high catalytic activity displayed by the enzyme. Moreover, PhTX-II PLA2 showed an allosteric behavior and  its enzymatic activity was dependent on Ca2+. Examination of PhTX-II PLA2 by CD spectroscopy indicated a high content of alpha-helical structures, similar to the known structure of secreted phospholipase IIA group suggesting a similar folding. PhTX-II PLA2 causes neuromuscular blockade in avian neuromuscular preparations with a significant direct action on skeletal muscle function, as well as, induced local edema and myotoxicity, in mice. The treatment of PhTX-II by BPB resulted in complete loss of their catalytic activity that was accompanied by loss of their edematogenic effect. On the other hand, enzymatic activity of PhTX-II contributes to this neuromuscular blockade and local myotoxicity is dependent not only on enzymatic activity. These results show that PhTX-II is a myotoxic Asp49 PLA2 that contributes with toxic actions caused by P. hyoprora venom.<\/jats:p>","DOI":"10.3390\/toxins6113077","type":"journal-article","created":{"date-parts":[[2014,10,31]],"date-time":"2014-10-31T10:32:28Z","timestamp":1414751548000},"page":"3077-3097","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["PhTX-II a Basic Myotoxic Phospholipase A2 from  Porthidium hyoprora Snake Venom,  Pharmacological Characterization and  Amino Acid Sequence by Mass Spectrometry"],"prefix":"10.3390","volume":"6","author":[{"given":"Salom\u00f3n","family":"Huancahuire-Vega","sequence":"first","affiliation":[{"name":"Department of Biochemistry, Institute of Biology, State University of Campinas (UNICAMP),  P.O. Box 6109, 13083-970 Campinas, SP, Brazil"},{"name":"Department of Biochemistry and Pharmacology, Faculty of Health Sciences, Medicine School, Union Peruvian University (UPeU), Lima 15, Peru"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luis","family":"Ponce-Soto","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Institute of Biology, State University of Campinas (UNICAMP),  P.O. Box 6109, 13083-970 Campinas, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sergio","family":"Marangoni","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Institute of Biology, State University of Campinas (UNICAMP),  P.O. Box 6109, 13083-970 Campinas, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2014,10,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"347","DOI":"10.1590\/S0036-46652013000500009","article-title":"Epidemiological profile of snakebite accidents in a metropolitan area of northeast Brazil","volume":"55","author":"Albuquerque","year":"2013","journal-title":"Rev. Inst. Med. Trop. Sao Paulo"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"617","DOI":"10.1590\/0037-8682-0130-2013","article-title":"Snakebite cases in the municipalities of the State of Para\u00edba, Brazil","volume":"46","author":"Oliveira","year":"2013","journal-title":"Rev. Soc. Bras. Med. Trop."},{"key":"ref_3","unstructured":"Campbell, J.A., and Lamar, W.W. (2004). 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