Structure of Escherichia coli aspartate alpha-decarboxylase Asn72Ala: probing the role of Asn72 in pyruvoyl cofactor formation
Webb, M.E., Lobley, C.M., Soliman, F., Kilkenny, M.L., Smith, A.G., Blundell, T.L., Abell, C.(2012) Acta Crystallogr Sect F Struct Biol Cryst Commun 68: 414-417
- PubMed: 22505409 
- DOI: https://doi.org/10.1107/S1744309112009487
- Primary Citation of Related Structures:  
3TM7 - PubMed Abstract: 
The crystal structure of the Asn72Ala site-directed mutant of Escherichia coli aspartate α-decarboxylase (ADC) has been determined at 1.7 Å resolution. The refined structure is consistent with the presence of a hydrolysis product serine in the active site in place of the pyruvoyl group required for catalysis, which suggests that the role of Asn72 is to protect the ester formed during ADC activation from hydrolysis. In previously determined structures of activated ADC, including the wild type and other site-directed mutants, the C-terminal region of the protein is disordered, but in the Asn72Ala mutant these residues are ordered owing to an interaction with the active site of the neighbouring symmetry-related multimer.
Organizational Affiliation: 
University Chemical Laboratory, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, England. m.e.webb@leeds.ac.uk