Numerical study on interactions of atmospheric plasmas and peptides by reactive molecular dynamic simulations.

Experimental observations have shown that peptides are chemically modified under plasma treatment, which impacts the function and lifetime of a protein. This paper investigates the interactions of reactive oxygen species (ROS) produced in atmospheric plasmas and peptides. Results show that the reactions typically start with the H abstraction from the side chain of amino acids. As the reactions continue, the introduction of O atoms is the most common reaction, and the formation of double C = C bonds, detachment of carboxyl groups, and cleavage of the ring are also observed. Moreover, the degree of oxidative modification of the peptides increases with increasing doses of ROS. This study reveals the formation and breaking of chemical bonds and the generation of new reactive groups in the structure of peptides under plasma treatment, which enables us to understand the mechanisms of plasma medicine deeply. [ABSTRACT FROM AUTHOR]