Graph Theoretical Analysis of Endomorphin

“Graph theoretical analysis” [6] is a significant field of biological networks. Nowadays it gives a new direction to worldwide research. A Pt-graph of a protein or peptide is introduced by us rooted in some properties (physical and chemical) and amino acids’ adjacency equivalent to each protein or peptide. Here we analyze the Pt-graph of Endomorphin. We have some observations relating to their relations among the properties (physical and chemical). The Pt-graph of Endomorphin is a connected graph. The average degree of the Pt-graph is 1.5. The hydrophobic amino acids like Proline (P) and Tryptophan (W) have received the highest value of all measures of centrality. The hydrophobic and aromatic amino acids, Tyrosine (Y) and Phenylalanin (F) received the lowest values of all measures of centrality. It will help in the study of drug design and the evolution of proteins or peptides.