Magnesium and calcium cation–ligand interactions within the pseudopotential approach. II. Cation–GABA interactions

✍ Scribed by I. Ortega Blake; A. Leś

• Publisher: John Wiley and Sons
• Year: 1981
• Tongue: English
• Weight: 730 KB
• Volume: 19
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/qua.560190309

✦ Synopsis

Abstract

We performed ab initio pseudopotential and CNDO calculations on γ‐aminobutyric acid (GABA) and its Ca^2+^ and Mg^2+^ clathrates. We were particularly interested in the rotational barrier existing between two extreme conformers of GABA and its modification upon metal complexing. We found that the pseudopotential method predicts a coordination of the ions to GABA and that this coordination inverts the rotational barrier observed for the isolated molecule. We also looked into the adequacy of CNDO for the study of this type of coordination and found several shortcomings in its predictions. The biological implications of these findings are discussed and a hypothesis on the role of a GABA–Ca^2+^ complex is presented.