Prospecting of Anti-Cancer Peptides (ACPs) from proteome of muscle tissue from Indian walking catfish, Clarias magur (Hamilton 1822) by Mass spectrometry and in silico approaches

Abstract

The freshwater walking catfish Clarias magur (Hamilton, 1822) is one of the most popular aquaculture fishes in Indian and the Asian subcontinent because of its nutritional value and great taste. Muscle proteome of C. magur was studied. Muscle tissue is of significance in fishes due to presence of high protein content and poly unsaturated fatty acids (PUFA) proved to have medicinal and therapeutic value. Fishes procured were acclimatised and muscle tissue was studied. Briefly, muscle protein extract prepared from C. magur, by homogenizing muscle tissue in 50 mMTris buffer with protease inhibitor for downstream processing, digested with trypsin in solution, reduced with dithiothreitol (DTT) and alkylated with iodoacetamide (IAA) for LC/MS analysis. The peptides were separated on Waters Synapt G2 Q-TOF equipped with Electro-Spray ionisation (ESI) for DATA independent acquisition for MS analysis. The raw data was processed by Protein Lynx Global Server (PLGS) software. Peptide tolerance limit was set at 50 ppm with minimum fragment match of 2 peptides for proteins. In silico approach was used to retrieve ACPs from muscle proteome derived from LC/MS by BIOPEP, Anti-CP and iDACP online servers. Out of a total of 468 peptides, 60 peptides showed anti-cancer peptide (ACPs) activity. Out of 19 non-allergenic peptides as analysed by AlerPred software, one peptide was toxic as revealed by ToxinPred software. The peptides were ranked with 0.9884 being highest and 0.0341 being the lowest by Peptide Ranker tool. This study reports C. magur derived anti-cancer bioactive peptides as a natural, less toxic anti-cancer therapeutic source exhibiting anti-cancer activity by activating apoptosis in mitochondria slaying cancer cells.