10.1002/chem.201701591
Chemistry - A European Journal
COMMUNICATION
involved, namely N4, O2, N10 and O9*, with residues in the
vicinity (Figure 1 and Scheme S3). The interactions of O2 affect
the basicity of N4 since these two atoms are conjugated in the
same manner that O9* is conjugated with N10. An extended
network of the solvent structure in the crystal (Scheme S3)
appears to connect Asp339 OE1, through w253 and w254 with
both N4 and O9*. O2 and N10, in turn, form water-mediated
interactions with Glu88 through water molecules w249, w250
and w251, respectively. Additionally, O2 and N10 interact
through w249 with Asp283, a key residue that belongs to the
Keywords: Glycogen Phosphorylase • Acridone based Inhibitor
• X-ray crystallography • optical spectra • quantum chemistry
calculations •
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Acknowledgements
[22] K. P. Tan, T.B. Nguyen, S. Patel, R. Varadarajan, M. S. Madhusudhan
Nucl. Acids Res. 2013, 41, W242-W321
This work was supported by Heracleitus II (awarded to MM),
“BioStruct-X” (FP7/No. 283570) (for access to PETRA III
synchrotron, projects 1196 & 3976 to EDC), LASERLAB-
EUROPE (FP7 No. 284464) and “Progetto Bandiera” N-CHEM
(AV). We acknowledge EMBL P13/P14 PETRA III scientists for
help during data collection (EDC) and Prof. M. A. Miranda for
initial discussions (TG).
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39, W242-248
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