[SA_Scat] New MEMPROT release

[PEREZ Javier]

Dear all,
Please find recent news from our MEMPROT program.
Have a nice day !
Javier

MEMPROT is an application meant to build a space-filling model of a detergent corona around a transmembrane protein, based on SAXS data fitting.

Welcome to Memprot Release 2! In the new version, we are happy to present:

1. New features:

1.1. Crysol 3 support.
While Crysol 3 is *much* slower than Crysol 2, our initial tests suggest that it is significantly better for many proteins, especially transmembrane transporters and other proteins with big, long channels.
Choose the version of Crysol you want to use with Memprot with one simple switch!

1.2. Adaptive Shape Algorithms.
Two independent algorithms were implemented that make the surface of the detergent corona follow/mimic the surface of the transmembrane part of the protein. This enables attempts to model the corona around the proteins whose cross-section deviates significantly from an ellipsoid. Again the choice between different algorithms can be easily controlled by one simple variable

1.3. Various code optimisations.
Memprot 2 is faster and the speed of the calculations is now limited by Crysol (especially when using Crysol 3). You can see it by yourself - a set of rudimentary timers was implemented.

1.4. Rudimentary Manual.
We started working on documentation of Memprot so that all information about it can be found in a single, easily available place. In this iteration we laid the fundaments.

2. Bugfixes:

2.1. The option to limit the data by the qmin variable was not working properly in previous releases. It should now work correctly.
2.2. Output format in Crysol 2 changed slightly recently. Memprot has been adapted accordingly.

3. *Tentative* plans for future:

3.1. Steepest Descent minimization: save time by going straight to (hopefully global) minimum of Chi^2 space
3.2. Parallelization: save time by calculating many models at the same time on your local HPC cluster
3.3. Support for programs alternative to Crysol: Check if your model gives consistently good fits across different programs.
3.4. Improvements to Memprot Manual:

MEMPROT can be found on (also brand new) Soleil Website:
French:
https://www.synchrotron-soleil.fr/fr/lignes-de-lumiere/swing
English:
https://www.synchrotron-soleil.fr/en/beamlines/swing

Memprot is a young program! We will *VERY MUCH* appreciate any questions, comments, suggestions and bug reports! Please write to us:
Javier Pérez: javier.perez at synchrotron-soleil.fr<mailto:javier.perez at synchrotron-soleil.fr>
Maciej Baranowski: maciej.baranowski at synchrotron-soleil.fr<mailto:maciej.baranowski at synchrotron-soleil.fr>



Javier Pérez
Group leader - Beamline SWING
Synchrotron SOLEIL
Saint-Aubin - BP 48
91192 Gif sur Yvette Cedex
France
Tel : +33 (0)1 69 35 96 19 (office)
        +33 (0)1 69 35 97 53 (beamline)
javier.perez at synchrotron-soleil.fr<mailto:javier.perez at synchrotron-soleil.fr>
http://www.synchrotron-soleil.fr/portal/page/portal/Recherche/LignesLumiere/SWING