Structure-function relationship of trichosanthin.

Y B Ke; J K Chen; H L Nie; X H He; X Y Ke; Y H Wang

doi:10.1016/s0024-3205(96)00676-5

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PubMed · 9042374

Structure-function relationship of trichosanthin.

Y B Ke·J K Chen·H L Nie·X H He·X Y Ke·Y H Wang

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Abstract

Trichosanthin (TCS), a 27 kDa ribosome inactivating protein extracted from the root tuber of Trichosanthes plant, was subjected to limited chymotrypsin digestion and three peptide fragments designated TCS-F1 72-247, TCS-F2 100-247, and TCS-F3 133-247 were generated. The RNA-N-glycosidase and cytotoxic activities of the TCS fragments were compared with that of inact TCS. TCS-F1 and TCS-F2 were biologically active, while TCS-F3 was completely inactive. Dose-dependent studies showed that TCS-F1 and TCS-F2 were less potent in their trophoblast cytotoxicity than intact TCS, however, full biological effect could still be obtained with a higher dosage. Based on the known three-dimensional structure of TCS, we postulate that the putative active site of TCS is located at amino acid residues 110 to 174.

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Chymotrypsin Electrophoresis, Polyacrylamide Gel Isoelectric Focusing Peptide Fragments Peptide Mapping Structure-Activity Relationship Trichosanthin Journal Article

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Y B Ke, J K Chen, H L Nie, X H He, X Y Ke, Y H Wang. 1997. Structure-function relationship of trichosanthin.. https://doi.org/10.1016/s0024-3205(96)00676-5

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