Data Entry: Please note that the research database will be replaced by UNIverse by the end of October 2023. Please enter your data into the system https://universe-intern.unibas.ch. Thanks

Login for users with Unibas email account...

Login for registered users without Unibas email account...

 
A large hinge bending domain rotation is necessary for the catalytic function of Escherichia coli 5 `-nucleotidase
JournalArticle (Originalarbeit in einer wissenschaftlichen Zeitschrift)
 
ID 755156
Author(s) Schultz-Heienbrok, R.; Maier, T.; Strater, N.
Author(s) at UniBasel Maier, Timm
Year 2005
Title A large hinge bending domain rotation is necessary for the catalytic function of Escherichia coli 5 `-nucleotidase
Journal Biochemistry
Volume 44
Number 7
Pages / Article-Number 2244-2252
Abstract Two variants of Escherichia coli 5`-nucleotidase with disulfide bridges that were engineered to link the two domains of the protein were used to demonstrate that a large domain rotation is required for the catalytic mechanism of the enzyme. Kinetic analysis demonstrates that the variant trapped in the open form is almost inactive but can be activated up to 250-fold by reduction of the disulfide bridge. The second variant can adopt a closed but also a half-open conformation despite the presence of the cystine linkage. As a result of this flexibility, the mutant is still active in its oxidized state, although it shows a more pronounced substrate inhibition than the wild-type protein. A theoretical model is proposed that allows estimation of the flexibility of the proteins in the presence of the disulfide domain cross-link. Despite the unexpected residual flexibility of the trapped mutants, the enzymes could be used as conformational reporters in CD spectroscopy, revealing that the wild-type protein exists predominantly in an open conformation in solution. The kinetic, spectroscopic, and theoretical data are brought together to discuss the domain rotation in terms of the kinetic functioning of E. coli 5`-nucleotidase.
Publisher American Chemical Society
ISSN/ISBN 0006-2960 ; 1520-4995
edoc-URL http://edoc.unibas.ch/45831/
Full Text on edoc No
Digital Object Identifier DOI 10.1021/bi047989c
ISI-Number 000227075200002
Document type (ISI) Article
 
   

MCSS v5.8 PRO. 0.331 sec, queries - 0.000 sec ©Universität Basel  |  Impressum   |    
28/03/2024