Adenosine kinase from Schistosoma mansoni: structural basis for the differential incorporation of nucleoside analogues

Romanello, L.; Bachega, J.F.R.; Cassago, A.; Brandão-Neto, J.; DeMarco, R.; Garratt, R.C.; Pereira, H.D.

doi:10.1107/S0907444912044800

Figure 4
Stereoview of a standard OMIT map (F_o - F_c) at 3 [sigma]

for AMP (a) and tubercidin (b) in the ATP-binding site (molecule A). The average B factor for tubercidin is very high (61.62 Å²) as a result of very loose contacts within the ATP-binding site, leading to less well defined electron density.