FREQUENCY OF DIPEPTIDES AND ANTIDIPEPTIDES

Oliviero Carugo

doi:10.5936/csbj.201308001

Abstract

Although it is reasonable to expect that the frequency of a generic dipeptide XY in proteins is the same of its counterpart YX, on the basis of an accurate statistical analysis of a large number of protein sequences, it appears that some dipeptides XY are considerably more frequent than their mirror images YX, referred to as antidipeptides. Given that it has been verified that this unexpected anisotropic frequency of occurrence is unbiased by the type of protein sequences that are analyzed, it is possible to conclude that this is a genuine phenomenon. Nevertheless, it was impossible to find the mechanism underlying this unexpected phenomenon, which does not seem to be related to diverse conformational propensities, to the different conformational flexibility of the peptide/antidipeptide pair, to dissimilar accessibility to the solvent or to gene random mutations.

Highlights

Proteins are made by 20 types of a-amino acids, which have from its counterpart BA
We considered structural different shapes, dimensions, structures, physicochemical properties features, like secondary structure, accessibility to the solvent or
On the other hand, we examined the amino acid properties have been used to predict a variety of protein possibility that random nucleotide mutations of the genes might cause features, ranging from subcellular location [4] to protein-protein the prevalence of one of the members of the dipeptide-antidipeptide interfaces [5]

Summary

Introduction

Proteins are made by 20 types of a-amino acids, which have from its counterpart BA. On the other hand, we examined the amino acid properties have been used to predict a variety of protein possibility that random nucleotide mutations of the genes might cause features, ranging from subcellular location [4] to protein-protein the prevalence of one of the members of the dipeptide-antidipeptide interfaces [5].

Results

Conclusion