Theoretical study of arginine-carboxylate interactions

• Type: Article in International Scientific Journal
• Date: 1999

Authors

Melo, A (Author) FCUP; Ramos, MJ (Author) FCUP; Floriano, WB (Author) Other; Gomes, JANF (Author) FCUP; Leao, JFR (Author) Other; Magalhaes, AL (Author) FCUP; Maigret, B (Author) Other; Nascimento, MC (Author) Other; Reuter, N (Author) Other

Journal

Title: Journal of Molecular Structure: THEOCHEM

Vol. 463

Pages: 81-90

ISSN: 0166-1280

Publisher: Elsevier B.V.

Indexing

ISI Web of Knowledge - 36 Citations

Scopus - 39 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-001-4JT

DOI: 10.1016/s0166-1280(98)00396-0

Abstract (EN): The importance of the guanidinium-carboxylate interactions has sprung from the observed salt bridges often present in biological systems involving the arginine-glutamate or arginine-aspartate side chains. The strength of these interactions has been explained on the basis of a great coulombic energy gain, due to the closeness of two charges of opposite sign and the occurrence of H-bond interactions. However, in some environments proton transfer, from guanidinium to carboxylate, can occur with the consequent annihilation of charge. In this work, both ab-initio (6-31G** and MP2/6-31G**) and semi-empirical (AM1) calculations were performed in vacuo on appropriate models, methylguanidinium-acetate and methylguanidine-acetic acid to simulate the zwitterionic and the neutral forms, respectively. The results obtained indicate that, in solvent-free hydrophobic environments, the neutral form should be more stable than the zwitterionic one.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10