Abstract:
:Recent measurements have demonstrated enzyme activity at hydrations as low as 3%. This raises the question of whether hydration-induced enzyme flexibility is important for activity. Here, to address this, picosecond dynamic neutron scattering experiments are performed on pig liver esterase powders at 0%, 3%, 12%, and 50% hydration by weight and at temperatures ranging from 120 to 300 K. At all temperatures and hydrations, significant quasielastic scattering intensity is found in the protein, indicating the presence of anharmonic, diffusive motion. As the hydration increases, a temperature-dependent dynamical transition appears and strengthens involving additional diffusive motion. The implication of these results is that, although the additional hydration-induced diffusive motion in the protein detected here may be related to increased activity, it is not required for the enzyme to function.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Kurkal V,Daniel RM,Finney JL,Tehei M,Dunn RV,Smith JCdoi
10.1529/biophysj.104.058677subject
Has Abstractpub_date
2005-08-01 00:00:00pages
1282-7issue
2eissn
0006-3495issn
1542-0086pii
S0006-3495(05)72775-2journal_volume
89pub_type
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