Title:	Interaction of the mononucleotide UMP with a fluid phospholipid bilayer†
Authors:	Sasidharan, Sreeja Raghunathan, V.A. +4 Co-Authors
Issue Date:	28-Oct-2019
Publisher:	Royal Society of Chemistry
Citation:	Soft Matter, 2019, Vol.15, p8129
Abstract:	Interaction between mononucleotides and lipid membranes is believed to have played an important role in the origin of life on Earth. Studies on mononucleotide-lipid systems hitherto have focused on the influence of the lipid environment on the organization of the mononucleotide molecules, and the effect of the latter on the confining medium has not been investigated in detail. We have probed the interaction of the mononucleotide, uridine 5′-monophosphate (UMP), and its disodium salt (UMPDSS) with fluid dimyristoylphosphatidylcholine (DMPC) membranes, using small-angle X-ray scattering (SAXS), cryogenic scanning electron microscopy (cryo-SEM) and computer simulations. UMP adsorbs and charges the lipid membrane, resulting in the formation of unilamellar vesicles in dilute solutions. Adsorption of UMP reduces the bilayer thickness of DMPC. UMPDSS has a much weaker effect on interbilayer interactions. These observations are in very good agreement with the results of an all-atom molecular dynamics simulation of these systems. In the presence of counterions, such as Na+, UMP forms small aggregates in water, which bind to the bilayer without significantly perturbing it. The phosphate moiety in the lipid headgroup is found to bind to the hydrogens from the sugar ring of UMP, while the choline group tends to bind to the two oxygens from the nucleotide base. These studies provide important insights into lipid–nucleotide interactions and the effect of the nucleotide on lipid membranes.
Description:	Restricted Access.
URI:	http://hdl.handle.net/2289/7356
ISSN:	1744-683X 1744-6848 (Online)
Alternative Location:	http://dx.doi.org/10.1039/C9SM01257E
Copyright:	2019 Royal Society of Chemistry
Additional information:	Supplementary information Available
Appears in Collections:	Research Papers (SCM)

Items in RRI Digital Repository are protected by copyright, with all rights reserved, unless otherwise indicated.