Thursday, November 24, 2022

NMRlipids databank: First draft of the manuscript

The first draft of the manuscript describing the NMRlipids databank is now available in this repository (main text and SI). It contains descriptions of the databank structure (as discussed in the Current status and structure post) and quality evaluation (as discussed in the Form factor quality evaluation update post). In addition, applications of the NMRlipids databank are demonstrated by analysing lipid flip-flops and water anisotropic diffusion from all the 714 simulations that are currently in the databank.

I have an ambitious plan to submit the manuscript by the end of this year due to the upcoming end of my funding and grant application deadlines. Therefore, I would appreciate receiving comments about the manuscript relatively soon. The results about lipid flip-flops and anisotropic water diffusion that are currently in the manuscript are summarized below.

The project is organized in three GitHub repositories. The Databank repository contains the core databank, the DataBankManuscript repository contains the analyses and results for the manuscript, and the DataBankManuscriptText repository contains the manuscript text. You can add your comments to issues of any of these repositories or to this blog post.

Detection rare phenomena using NMRlipids databank: Cholesterol flip-flops Flip-flops between bilayer leaflets were observed for cholesterol, DCHOL (18,19-di-nor-cholesterol), DOG (1,2-dioleoyl-sn-glycerol), and SDG (1-stearoyl-2-docosahexaenoyl-sn-glycerol), but not for other lipids in the NMRlipids databank. For cholesterol we observed 635 flip-flop events in 78 different simulations. Therefore, we analyzed the how cholesterol flip-flop rate depends on membrane properties. Cholesterol flip-flop rates and their averages over fixed ranges of x-axis values are plotted as a function of membrane thickness, lateral density and order in Fig. 1. The results reveal a non-linear correlation between decreasing cholesterol flip-flop rate and membrane packing.