| Changing the metal ion selectivity of rabbit muscle enolase by mutagenesis: effects of the G37A and G41A mutations. | |
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MedLine Citation:
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PMID: 15752688 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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During the reaction catalyzed by enolase, a mobile loop, residues 36-45, closes over the active site. In order to probe the role of this loop movement in catalysis, the glycines at positions 37 and 41 of rabbit muscle enolase (beta beta) have been mutated to alanines. The mutant forms-G37A and G41A-of enolase are both active, but have altered selectivity for divalent cations. G37A, when assayed with Mg(2+), has 12% the activity of the wild type. However, it is twice as active as wild type when assayed with Mn(2+), Zn(2+), or Co(2+). G41A has 4% the activity of the wild type with Mg(2+), is more active than wild type with Co(2+), and slightly less active than wild type with Mn(2+) and Zn(2+). The kinetic isotope effect for both mutants is greater than that of the wild type with all 4 divalent cations. These results indicate that the flexibility of this loop has subtle effects on catalytic activity. |
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Authors:
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Mary Judith Kornblatt |
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Publication Detail:
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Type: Journal Article; Research Support, Non-U.S. Gov't Date: 2004-12-31 |
Journal Detail:
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Title: Biochimica et biophysica acta Volume: 1748 ISSN: 0006-3002 ISO Abbreviation: Biochim. Biophys. Acta Publication Date: 2005 Apr |
Date Detail:
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Created Date: 2005-03-08 Completed Date: 2005-04-28 Revised Date: 2006-11-15 |
Medline Journal Info:
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Nlm Unique ID: 0217513 Medline TA: Biochim Biophys Acta Country: Netherlands |
Other Details:
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Languages: eng Pagination: 20-5 Citation Subset: IM |
Affiliation:
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Enzyme Research Group, Department of Chemistry and Biochemistry, Concordia University, Montreal, Quebec, Canada H4B 1R6. judithk@vax2.concordia.ca |
Export Citation:
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| MeSH Terms | |
Descriptor/Qualifier:
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Animals Circular Dichroism Glycine / metabolism Ions / chemistry* Metals / chemistry* Muscle, Skeletal / enzymology* Mutagenesis, Site-Directed Phosphopyruvate Hydratase / chemistry*, genetics*, metabolism Protein Structure, Secondary Rabbits |
| Chemical | |
Reg. No./Substance:
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0/Ions; 0/Metals; 56-40-6/Glycine; EC 4.2.1.11/Phosphopyruvate Hydratase |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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