Multiple Forms of Glucosephosphate Isomerase in Maize

Erythrocyte membrane proteins in hereditary glucosephosphate isomerase deficiency.

Erythrocytes (approximately equal to 50% reticulocytes) obtained from a splenectomized patient with a thermolabile variant of glucosephosphate isomerase (GPI) deficiency showed a striking degree of crenation and decreased filterability through 3-micrometer Nuclepore filters (Nuclepore Corp., Pleasanton, Calif.). Membranes prepared by hypotonic lysis of such erythrocytes were found to contain a...

Thermostability characteristics of glucosephosphate and triosephosphate isomerase in erythrocytes from several species.

Significant differences in the thermostability of both glucosephosphate and triosephosphate isomerase were noted among a series of six primate and five nonprimate species. The enzyme structural differences among species, as assessed by thermostability profiling, was greater than expected from electrophoretic mobility patterns. Microheterogeneity of GPI, i.e. differences in thermostability withi...

Affinity labeling and characterization of the active site histidine of glucosephosphate isomerase. Sequence homology with triosephosphate isomerase.

N-Bromoacetylethanolamine phosphate was found to act as a specific affinity label for the active center of glucosephosphate isomerase. The inactivation process followed pseudo-first order kinetics, was irreversible and exhibited rate saturation kinetics with minimal half-lives of inactivation of 4.5 and 6.3 min for the enzyme isolated from human placenta and rabbit muscle, respectively. The pH ...

Glucosephosphate isomerase deficiency: evidence for in vivo instability of an enzyme variant with hemolysis.

Linkage analysis of the multilocus glucosephosphate isomerase isozyme system in sunfish (Centrarchidae, Teleostii).

The purpose of the present investigation is to determine whether the two duplicated glucosephosphate isomerase (EC 5.3.1.9) loci Gpi-A and Gpi-B reside on the same chromosome in teleostean fishes. Interspecific sunfish hybrids were employed for the cross because of the different species-specific electrophoretic mobilities of the allelic isozymes at each GPI locus and because of their genomic co...