Attractive interactions between side chains of histidine-histidine and histidine-arginine-based cationic dipeptides in water.
Molecular dynamics simulations of histidine-based dipeptides in water show that a protonated histidine side chain group has a propensity for forming like-charged contact pairs with another protonated histidine or with arginine. This effect is of similar strength to that in previously observed arginine-arginine pairing. Even stronger contact pairs are formed in singly protonated or deprotonated dihistidine, where stacking of aromatic rings is not weakened by Coulomb repulsion between the side chains. Similar pairing behavior is also observed in a mixed solution of imidazole and imidazolium chloride.
Introduction: The Nef accessory protein is an attractive antigenic candidate in the development of HIV-1 DNA- or protein-based vaccines. The most crucial disadvantage of DNA and protein-based vaccines is their low immunogenicity, which can be improved by cell-penetrating peptides (CPPs) as effective carrier molecules. Methods: In this study, the HIV-1 Nef protein was generated in the Escherichi...متن کامل
Secondary Structure Effects on the Acidity of Histidine and Lysine-Based Peptides Model; A Theoretical Study
In this study, the effect of the secondary structure of the protein on the acid strength of three structures of random (R), alpha helix (α) and beta sheet (b) were investigated theoretically. These structures are related to the cationic amino acids of histidine and lysine in the polypeptide chain of eight-glycine residue. Computational methods at the HF, B3LYP, X3LYP and M05-2X levels in t...متن کامل
In the present work, an extensive theoretical calculation study on Histidine-Histidine dipeptide in gas phase is done by using DFT method with Gaussian 98 program. Through investigations on the molecular geometries of this molecule it is found that there is six rings in the molecules not two rings. The presence of four intramolecular hydrogen bonds is responsible for the formation of additional...متن کامل
Evidence for the Essential Arginine and Histidine Residues in Catalytic Activity of Glucose 6-Phosphate Dehydrogenase from Streptomyces aureofaciens
Glucose 6-phosphate dehydrogenase (G6PD) was purified from Streptomyces aureofaciens and inactivated with butanedione and diethylpyrocarbonate. Incubation of the enzyme with butanedione resulted in a rapid activity loss (80%) within 5 min, followed by a slow phase using a molar ratio to enzyme concentration of 100. Fluorescence studies showed a conformational change in the butanedione-modified ...متن کامل
The peptide-based porous 3D framework, ZnCar, has been synthesized from Zn(2+) and the natural dipeptide carnosine (β-alanyl-L-histidine). Unlike previous extended peptide networks, the imidazole side chain of the histidine residue is deprotonated to afford Zn-imidazolate chains, with bonding similar to the zeolitic imidazolate framework (ZIF) family of porous materials. ZnCar exhibits permanen...متن کامل