Re: [ccp4bb] on resolution and explaination of the intersubunit bonds

2015-05-24 Thread James Holton
Formally, the "resolution" of any image is the minimum distance between two objects in the image that can be "resolved", or separated. Think of two Gaussian-shaped peaks that are 4 A apart. If you "blur" the image enough, eventually the two peaks merge into one, and there is no longer a val

Re: [ccp4bb] on b-factor

2015-05-24 Thread James Holton
A B factor is the result of a curve fit. It is a big, complicated 3D curve fit with internal couplings between parameters, but at the end of the day macromolecular model refinement is still a "curve fit". It is instructive to think of a linear slice through the map, because that way you have

Re: [ccp4bb] on b-factor

2015-05-24 Thread Artem Evdokimov
By data quality combined with data treatment and the correctness of the final model. B-factors can be radically affected by incorrectly modeled regions, as well as post-collection data treatment. Artem - Cosmic Cats approve of this message On Sun, May 24, 2015 at 12:49 AM, Smith Liu wrote: > D

Re: [ccp4bb] on resolution and explaination of the intersubunit bonds

2015-05-24 Thread Artem Evdokimov
The use of resolution as sole criterion for validity of observations is not advisable. Interactions are inferred from the coordinates of interacting residues which are determined by examination of local electron density features. If you cannot assign rotamers etc. based on your electron density, th

Re: [ccp4bb] SUMMARY: Equation Editor woes with Office 2011 for Mac

2015-05-24 Thread SIMON WESTRIP
It seems that LaTeXit already does this! I hope to be able to extract the source from any LaTeXit graphics that are included in e.g. Word documents as part of the document processing system used by IUCr journals, thus easing the route to publication. I am all considering producing a similar tool

[ccp4bb] on resolution and explaination of the intersubunit bonds

2015-05-24 Thread Smith Liu
Dear All, In order to acceptably explain the salt bridges, hydrophobic interactions and H-bonds among subunits in the crystal structure of a protein complex, is there a threshold resolution of the crystal, for example, if the crystal is poorer than 4A or 5A, the crystal structure solved cannot