[Chimera-users] Molmap incorporation of B-factors

[Oliver Clarke]

Hi all,

For the purposes of model validation, I’d like to analyze local correlation of my model with the experimental map (and color it on either/both the model or map). I figured the easiest way to do this is to use molmap to generate a synthetic map, then use vop local correlation to generate a correlation map which I can use to color either the model or map (using scolor or “Values at Atom Positions”). 

This works fine, and generates informative looking pictures, I just wanted to clarify exactly what molmap is doing, to make sure I understand it. 

Am I correct in thinking molmap does not use a per-atom temperature factor (or alter the width of the gaussian depending on the atomic B-factor)? 

Because if this is the case I guess the way I am doing things will exaggerate how bad the model is in regions where the B-factor is high and the density weak (which is not the worst thing in the world - better than having an unrealistically rosy view of one’s model!). 

Would it be possible to incorporate atomic B-factors into molmap calculations for Chimera 2? Or does anyone know of an external program that will perform a similar calculation (I know I can generate RSCC plots in Phenix which must be doing this internally, but I rather like displaying it on the model and map for ease of interpretation).

Cheers,
Oliver.