In:
Science, American Association for the Advancement of Science (AAAS), Vol. 341, No. 6148 ( 2013-08-23), p. 899-903
Abstract:
Many studies have implicated a role for conformational motions during the catalytic cycle, acting to optimize the binding pocket or facilitate product release, but a more intimate role in the chemical reaction has not been described. We address this by monitoring active-site loop motion in two protein tyrosine phosphatases (PTPs) using nuclear magnetic resonance spectroscopy. The PTPs, YopH and PTP1B, have very different catalytic rates; however, we find in both that the active-site loop closes to its catalytically competent position at rates that mirror the phosphotyrosine cleavage kinetics. This loop contains the catalytic acid, suggesting that loop closure occurs concomitantly with the protonation of the leaving group tyrosine and explains the different kinetics of two otherwise chemically and mechanistically indistinguishable enzymes.
Type of Medium:
Online Resource
ISSN:
0036-8075
,
1095-9203
DOI:
10.1126/science.1241735
Language:
English
Publisher:
American Association for the Advancement of Science (AAAS)
Publication Date:
2013
detail.hit.zdb_id:
128410-1
detail.hit.zdb_id:
2066996-3
detail.hit.zdb_id:
2060783-0
SSG:
11
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