Stereochemical Analysis of Glycerophospholipids by Vibrational Circular Dichroism

Abstract

The stereochemistry of glycerophospholipids (GPLs) has been of interest for its roles in the evolution of life and in their biological activity. However, because of their structural complexity, no convenient method to determine their configuration has been reported. In this work, through the first systematic application of vibrational circular dichroism (VCD) spectroscopy to various diacylated GPLs, we have revealed that their chirality can be assigned by the sign of a VCD exciton couplet generated by the interaction of two carbonyl groups. This paper also presents spectroscopic evidence for the stereochemistry of GPLs isolated from bacteria, eukaryotes, and mitochondria.

Advances and unresolved challenges in the structural characterization of isomeric lipids

“…This approach is routinely employed for probing the secondary structure of proteins, and binding of lipids to proteins [92], however the sample must be pure and solvent absorption effects must be taken into account when interpreting the resulting CD spectrum. An extension of this approach is Vibrational Circular Dichroism (VCD) which has been used to probe the chirality of glycerophospholipids, exploiting the VCD activity arising from the interaction of the two carbonyl groups on the fatty acyl chains [93].…”

Towards the Limits of Vibrational Circular Dichroism Spectroscopy: VCD Spectra of Some Alkyl Vinylethers

“…When such situations occur, vibrational circular dichroism (VCD) may prove a powerful and relatively easy tool to assess absolute configurations and even support relative configurations determined with other methods. Successful applications of VCD in this field are, among others, absolute configuration determination of alkanes, terpenes, and glycerophospholipids …”

“…Successful applications of VCD in this field are, among others, 13 absolute configuration determination of alkanes, 14 terpenes, 15,16 and glycerophospholipids. 17 Taking advantage of our relatively vast collection of chiral molecules spanning several classes of organic compounds, we decided to undertake a chiroptical analysis of vinyl ethers. These compounds are used as monomers for the preparation of chiral polyvinylethers, that is, polyethylenes appended with chiral ether pendants.…”

Synthesis of Phosphatidylcholines Possessing Functionalized Acids at sn-2, and 13C–14N and 13C–31P Couplings in Their 13C NMR Spectra

“…However, such couplings were not presented in latter publications dealing with PCs possessing two pure acid components at sn-1 and -2 positions. 15b,16c, 19 One might infer that the close signals reflected the difference between structurally similar acid components and diastereomers. 20 To address to the inconsistency, we measured 13 C NMR spectra of structurally homogeneous PCs 3h,i,j as well as diastereomeric PCs 3a-g in CD 3 OD.…”