1. Natural and artificial mutants of the human 2,3-bisphosphoglycerate as a tool for the evaluation of structure-function relationships.
- Author
-
Garel MC, Lemarchandel V, Prehu MO, Calvin MC, Arous N, Rosa R, Rosa J, and Cohen-Solal M
- Subjects
- 2,3-Diphosphoglycerate, Amino Acid Sequence, Base Sequence, Bisphosphoglycerate Mutase biosynthesis, Cloning, Molecular, DNA genetics, Escherichia coli genetics, Gene Expression, Humans, Molecular Sequence Data, Plasmids, Structure-Activity Relationship, Bisphosphoglycerate Mutase genetics, Diphosphoglyceric Acids metabolism, Mutation, Phosphotransferases genetics
- Abstract
2,3-bisphosphoglycerate mutase is a multifunctional enzyme which catalyses in red blood cells the synthesis and the degradation of 2,3-bisphosphoglycerate, the allosteric effector of hemoglobin. In order to study the structure-function relationships in BPGM, an expression vector was constructed which yielded an active protein, but with a modified electrophoretic mobility, due to a non-blocked N-terminal residue. Using site directed mutagenesis, mutants were produced with shortened chains. Results indicated the importance of residues 252-256 for the function. A natural deficient mutant with the substitution 89 Arg----Cys was described. Artificial mutant with the same substitution reproduced the same defect, as well as mutants Arg----Gly and Arg----Ser, indicating the key role of Arg 89 in the enzymatic mechanism.
- Published
- 1990