The influence of aliphatic amino acid side g roups on the acidity of Lysine by density functional theory

The peptides are an amazing class of compounds. Although t hey are all constructed from relativ ely simple building blocks (the a mino acids) , they exhibit a remarkable range of biolog ical properties ; because of their medicinal properties that the study of peptides has becom e one of th e most active area of current resear ch [۱]. Lysi ne is an esse ntial amino acid, which means that the human body cannot synthesize it and must obtain it through food source s. The con cepts of acidity (Ka , p Ka = -log Ka ) and proton transfer are essential to physic al and structural chemistry [۲]. Oftentimes pKa values can be measured quite easily experimentally; however, many times chemists are interested in the pKa values of mole cules that h ave not been synthesized or for which experime nts are not straightforward. For instance, amino acids that a re part of a polypeptide chain have pKa values that very based on their local enviro nment , which are difficult to dete rmine [۳]. In this stud y we perfor med a theoretical calculation for determination of side group exchange effects on the Lysine acidity.

کلیدواژه ها:

Lysine ، Acidity c onstant ، solvation free energies ، DFT