Journal article

Novel Inhibitor Cystine Knot Peptides from Momordica charantia

Wen-Jun He, Lai Yue Chan, Richard J Clark, Jun Tang, Guang-Zhi Zeng, Octavio L Franco, Cinzia Cantacessi, David J Craik, Norelle L Daly, Ning-Hua Tan

PLoS ONE | PUBLIC LIBRARY SCIENCE | Published : 2013

Abstract

Two new peptides, MCh-1 and MCh-2, along with three known trypsin inhibitors (MCTI-I, MCTI-II and MCTI-III), were isolated from the seeds of the tropical vine Momordica charantia. The sequences of the peptides were determined using mass spectrometry and NMR spectroscopy. Using a strategy involving partial reduction and stepwise alkylation of the peptides, followed by enzymatic digestion and tandem mass spectrometry sequencing, the disulfide connectivity of MCh-1 was elucidated to be CysI-CysIV, CysII-CysV and CysIII-CysVI. The three-dimensional structures of MCh-1 and MCh-2 were determined using NMR spectroscopy and found to contain the inhibitor cystine knot (ICK) motif. The sequences of th..

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University of Melbourne Researchers

Grants

Awarded by National Basic Research Program of China


Awarded by National New Drug Innovation Great Project of China


Awarded by National Natural Science Foundation of China


Awarded by Natural Science Foundation of Yunnan Province


Funding Acknowledgements

This work was supported by the National Basic Research Program of China (2013CB127505, 2009CB522300), the National New Drug Innovation Great Project of China (2011ZX09307-002-02), the National Natural Science Foundation of China (21202174, U1032602, 91013002, 30725048), the foundation of Chinese Academy of Sciences (Hundred Talents Program), and the Natural Science Foundation of Yunnan Province (2012GA003). WJH is a recipient of a fellowship from the China Scholarship Council. NLD was supported by a Queensland Smart State Fellowship and is currently an ARC Future Fellow. DJC is a National Health and Medical Research Council Professorial Research Fellow. OLF is supported by Conselho Nacional de Desenvolvimento Cientifico e Tecnologico, Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior and Fundacao de Apoio a Pesquisa do Distrito Federal. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.