Mixed-SAM surfaces monitoring CTX-protein, part II: Analysis using molecular dynamics simulations.
Molecular dynamics simulations are performed to study the physical mechanism of cobra cardiotoxin (CTX) proteins adsorption on alkanethiol self-assembled monolayers (SAMs) composed of S(CH(2))(5)CH(3) and S(CH(2))(9)CH(3). The binding energy of the CTX protein to the SAM surface of different mixing ratios of alkanethiol chains is calculated. The results show that the affinity of CTX to SAM reaches a maximum value when the ratio S(CH(2))(5)CH(3):S(CH(2))(9)CH(3) is 1:1, which agrees with the measurements of atomic force microscope obtained in Part I of our dual paper. Moreover, the binding energy is found to be linearly proportional to the CTX-SAM contact area. The hydrophobicity on CTX residues, the flexibility of SAMs and the behavior of water molecules near the SAM surface are examined to understand how these parameters affect the adsorption of a CTX protein on SAM surfaces. In addition, the importance of modeling water molecules explicitly in the study of protein adsorption is demonstrated by applying different solvent models.
Hung
Shih-Wei
SW
Department of Engineering and System Science, National Tsing Hua University, Hsinchu, 30013, Taiwan. d947107@oz.nthu.edu.tw
Hsiao
Pai-Yi
PY
Chieng
Ching-Chang
CC
D000327:Adsorption; D004179:Cobra Cardiotoxin Proteins / Q000737:chemistry*; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D056004:Molecular Dynamics Simulation; D018583:Pliability; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013499:Surface Properties; D014867:Water
D004179:Cobra Cardiotoxin Proteins; D013438:Sulfhydryl Compounds; D014867:Water