An integrated in silico approach to understand protein-protein interactions: human meprin-ß with fetuin-A.

ABSTRACT

Human meprin-ß, a zinc metalloprotease belonging to the astacin family, have been found to be associated with many pathological conditions like inflammatory bowel disease, fibrosis and neurodegenerative disease. The inhibition of meprin-ß by various inhibitors, both macromolecular and small molecules, is crucial in the control of several diseases. Human fetuin-A, a negative acute phase protein involved in inflammatory disease, has recently been identified as an endogenous inhibitor for meprin-ß. In this computational study, an integrated in silico approach was performed using existing structural information of meprin-ß coupled with ab initio modelling of human fetuin-A to predict a rational model of the complex through protein-protein docking. Further, the models were optimized and validated to generate an ensemble of conformations through extensive molecular dynamics simulation. Virtual alanine scanning mutagenesis was explored to identify hotspot residues on both proteins significant for protein-protein interaction (PPI). The results of the study provide structural insight into PPI between meprin-ß and fetuin-A which can be useful in designing molecules to modulate meprin-ß activity. Communicated by Ramaswamy H. Sarma.