Int.J.Curr.Microbiol.App.Sci (2019) 8(6): 3160-3171 3160 Original Research Article https://doi.org/10.20546/ijcmas.2019.806.378 Computational Interaction Analysis of Cyprinus carpio Trypsin1 and Kunitz Type Soybean Protease Inhibitor Gulshan Kumar * , Munish Kumar, Gyandeep Gupta and Ranjeeta Kumari Division of Genetics and Biotechnology, ICAR- Central Institute of Fisheries Education, Versova - 400 061, Mumbai, India *Corresponding author ABSTRACT Introduction Aquaculture is the fastest growing food producing sector in the world. Global per capita fish availability has reached 20kg, which is achieved by the significant increase in the aquaculture production both from freshwater and brackish water (SOFIA, 2016). The Asian continent is predominant in aquaculture production, which includes many species like carps, catfishes, shellfish, pangasius, tilapia etc. The three Indian major carp (IMCs), namely catla (Catla. catla), rohu (Labeo. rohita) and mrigal (Cirrhinus. mrigala) contribute the bulk of production to the extent of 70 to 75% of the total freshwater fish production, followed by exotic carps comprising silver carp, grass carp and common carp forming the second important group contributing to the balance 25 to 30% (FAO, 2018). Among exotic carps, the Cyprinus carpio is the important cyprinid International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 8 Number 06 (2019) Journal homepage: http://www.ijcmas.com Common carp (Cyprinus carpio) is highly important culturable species in freshwater and cultured throughout the globe. Its farming require formulated feed with balance protein and energy. Most of the time fish meal is used as a protein source, but it is not acceptable from sustainability point of view. The replacement of fish meal by plant based protein source is advised. The limitation of plant based ingredients like soybean meal is the presence of anti-digestive factors in the form of several protease inhibitors. Kunitz type soybean protease inhibitor (SPI) is the most abundant protease inhibitor in soybean meal and it reduces the digestibility of feed. The data regarding molecular interaction and binding affinity of SPI with proteases is available in mammalian organism like pig but in fishes it has not been studied in detail. So the present study was conducted to gain insight into the protein-protein interaction and binding affinity of common carp trypsin (ccTrypsin1) and SPI using computational modelling. The sequence and 3D structure of ccTrypsin1 is highly similar to its mammalian counterpart pig. The protein-protein interaction analysis using knowledge based docking approach showed that the interaction was more or less similar like porcine trysin with SPI. The predicted binding affinity (-9.2 kcal/mol) and dissociation constant (1.9E-0.7) showed strong interaction between the interactor governed by strong attractive forces like electrostatic forces. Keywords Cyprinus carpio, Aquaculture, Protease inhibitor, Trypsin, Soybean meal, computational modelling Accepted: 24 May 2019 Available Online: 10 June 2019 Article Info