{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T04:38:25Z","timestamp":1789879105995,"version":"4.0.1"},"reference-count":17,"publisher":"Cambridge University Press (CUP)","issue":"2","license":[{"start":{"date-parts":[[2009,4,6]],"date-time":"2009-04-06T00:00:00Z","timestamp":1238976000000},"content-version":"unspecified","delay-in-days":10597,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Parasitology"],"published-print":{"date-parts":[[1980,4]]},"abstract":"<jats:title>Summary<\/jats:title><jats:p>Extracts of rhesus monkey erythrocytes infected with<jats:italic>Plasmodium knowlesi<\/jats:italic>were fractionated by polyacrylamide gel electrophoresis (PAGE) and several zones of endopeptidase activity were demonstrated by an imprint-digest method. The enzymes were active only under acid conditions; activity was detected at pH 3\u00b72 but not between pH 6\u00b74 and 8\u00b79 using haemoglobin, albumin or erythrocyte lysate as the substrate. Optimized PAGE conditions separated highly active parasite enzymes with<jats:italic>R<\/jats:italic><jats:sub><jats:italic>f<\/jats:italic><\/jats:sub>values of 73, 63 and 53 (\u00b1 7%), as well as a red cell endopeptidase,<jats:italic>R<\/jats:italic><jats:sub><jats:italic>f<\/jats:italic><\/jats:sub>44. Of two other minor bands of activity, one was associated with platelets.<\/jats:p>","DOI":"10.1017\/s0031182000000780","type":"journal-article","created":{"date-parts":[[2009,6,5]],"date-time":"2009-06-05T16:48:22Z","timestamp":1244220502000},"page":"323-330","source":"Crossref","is-referenced-by-count":23,"title":["Endopeptidases from<i>Plasmodium knowlesi<\/i>"],"prefix":"10.1017","volume":"80","author":[{"given":"E.","family":"Hempelmann","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R. J. 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