PMID:1095054
| Citation |
Masurekar, M and Brown, GM (1975) Partial purification and properties of an enzyme from Escherichia coli that catalyzes the conversion of glutamic acid and 10-formyltetrahydropteroylglutamic acid to 10-formyltetrahydropterol-gamma-glutamyglutamic acid. Biochemistry 14:2424-30 |
|---|---|
| Abstract |
An enzyme that catalyzes the conversion of L-glutamic acid and 10-formyl-H4folic acid (also known as 10-formyl-H4pteroylglutamic acid) to 10-formyl-H4pteroyl-gamma-glutamylglutamic acid has been purified by 74-fold from extracts of Escherichia coli. ATP, Mg-2+, and a monovalent cation (K+ or NH-4, but not Na+) are required for the enzyme to function. Radioactive and bioautographic analyses revealed the formation of a single product. This product was identified as 10-formyl-H-4pteroyl-gamma-glutamylglutamic acid from its spectral characteristics, its ability to be used effectively as a growth faster for Lactobacillus casei 7469, and from radioactive analysis that indicated the incorporation into the product of 1 mol glutamate/mol of 10-formyl-H-4pteroylglutamic acid utilized. The enzyme functions optimally at pH 9.0-9.8 and at 50 degrees. Its molecular weight is estimated at 42,000-43,000. The Km values are 180 muM for L-glutamic acid and less than 2 muM for (-) 10-formyl-H-4pteroylglutamic acid. The only other naturally occurring folate compounds with significant activity as substrate are H-4pteroylglutamic acid and 5,10-methylene-H-4pteroylglutamic acid; however, these compounds are not used as effectively (K-m values are 10-12 mu-M) as 10-formyl-H-4pteroylglutamic acid. |
| Links | |
| Keywords |
Adenosine Triphosphate/pharmacology; Ammonium Sulfate; Cations, Monovalent; Chromatography, DEAE-Cellulose; Chromatography, Gel; Escherichia coli/enzymology; Formic Acid Esters/metabolism; Glutamates/metabolism; Kinetics; Magnesium/pharmacology; Peptide Synthases/isolation & purification; Tetrahydrofolates/metabolism |
| edit table |
Significance
You can help EcoliWiki by summarizing why this paper is useful
Useful Materials and Methods
You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.
Annotations
<annotationlinks/>
EcoliWiki Links
Add links to pages that link here (e.g. gene, product, method pages)
References
See Help:References for how to manage references in EcoliWiki.