Dynamics of a mobile loop at the active site of Escherichia coli asparaginase
HP Aung, M Bocola, S Schleper, KH Röhm - Biochimica et Biophysica Acta …, 2000 - Elsevier
Asparaginase II from Escherichia coli is well-known member of the bacterial class II
amidohydrolases. Enzymes of this family utilize a peculiar catalytic mechanism in which a
pair of threonine residues play pivotal roles. Another common feature is a mobile surface
loop that closes over the active site when the substrates is bound. We have studied the
motion of the loop by stopped-flow experiments using the fluorescence of tryptophan
residues as the spectroscopic probe. With wild-type enzyme the fluorescence of the only …
amidohydrolases. Enzymes of this family utilize a peculiar catalytic mechanism in which a
pair of threonine residues play pivotal roles. Another common feature is a mobile surface
loop that closes over the active site when the substrates is bound. We have studied the
motion of the loop by stopped-flow experiments using the fluorescence of tryptophan
residues as the spectroscopic probe. With wild-type enzyme the fluorescence of the only …