After the publication of the Study of Plant Cyclic Peptide which produced an important summary in Chemical Reviews (2006, 106: 840, impact factor ranks first in Chemistry), which received the first prize of Yunnan Natural Science (2006), researcher TAN Ninghua was awarded funding from the National Outstanding Youth Fund to expand the study direction from finding plant cyclic peptide to researching the structure and function of plant cyclic peptide.
After nearly two years’ effort, they achieved many outstanding results. In the following study, 5 types of structure and compositions of 17 plant cyclic peptides of Violaceae, Cucurbitaceae, Rhamnaceae, Caryophyllaceae, Euphorbiaceae, Rubiaceae, Compositae, Rutaceae and Lamiaceae in the aspect of Plant Cyclic Peptide discovery, obtained 80 Cyclic Peptide, including 2 new frameworks, 30 new cyclic peptides; founded a new method of TLC rapid detection for Violaceae-type cyclic peptide (Ring protein) (that is, improve the methods of thin-layer coloration for the ring protein by Coomassie blue light G-250, (Chinese Science Bulletin, 2008, 53: 1671), chromatographic separation and structural research methods (collected in the new edition “Chinese Herbs Extraction Method”); separated 40 ring protein from 5 kinds of plants, half of which are new protein, obtained the first crystal structure of ring protein cooperated with professor David Craik, University of Queensland, Australia (Journal of Biological Chemistry, 2009, 284: 10672); the methods of using radix pseudostell cyclic peptide B as the medicine quality control of herb radix pseudostell was used by 2010 version of "Chinese Pharmacopoeia".
In the active cyclic peptide discovery and mechanism research, they screened the activities of more than 40 cyclic peptides, including more than 30 models of anti-tumor, anti-virus, anti-bacterial, immune, diabetes and hemolytic, finding that most screened cyclic peptide are with anti-tumor activity and discovered two sign molecular, that is, anti-tumor activity RA-V and the new anti-HSV-1 RA-V and new immune activity AS1; completed the analysis of 2 kinds of active cyclic peptide structure-activity; constructed 3D databases of 500 cyclic peptides; developed the study of conformation theory and cyclic peptide biosynthesis exploration of 3 cyclic peptides as well as their analogues.
