[ccp4bb]: Waters.......??

[raji <raji@lamar.colostate.edu>]

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Hello Everyone,
I am learning to add waters to my structure. My structure is at 2A resolution. 
I can see Fo-Fc peaks upto 3.5 sigma (also see 2Fo-Fc) in my density in 
regions very close to the sidechains of amino acid like lys, arg, glu, asp. 
There is often a water molecule within H-bonding distance to the observed 
peak.
I suspect that these peaks are waters. However, the distance between the peak 
and the N-/O-atom is about 2A, lesser than what I expected. What is the min. 
distance for it to be a water ? The density provides a continuous H-bonding 
chemistry and so I think it may be a water.
How does one deal with these peaks ??? 
Pl. share your suggestions/comments.
Thank you very much.
Raji

Rajeswari Edayathumangalam
Dept. of Biochemistry & Molecular Biology
Colorado State University
Fort Collins, CO 80523 USA