Modeling human glucose-6-phosphate dehydrogenase mutations using C. elegans GSPD-1

Area of Science:

• Biochemistry
• Genetics
• Model Organisms

Background:

• Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked disorder causing hemolytic anemia due to reduced NADPH.
• This condition results from genetic mutations affecting G6PD enzyme function.

Purpose of the Study:

• To investigate the biochemical effects of mutations in the C. elegans G6PD ortholog, GSPD-1.
• To evaluate GSPD-1 as a model organism for studying human G6PD deficiency.

Main Methods:

• Performed steady-state enzyme kinetics on wild-type and mutant GSPD-1 enzymes.
• Utilized protein homology modeling to analyze mutation effects on enzyme structure.

Main Results:

• The R252L mutant showed a 10-fold increase in K_M for glucose-6-phosphate and reduced specific activity (11% of wild-type).
• The D60N mutant exhibited decreased specific activity (59% of wild-type) and potential conformational changes.
• Homology modeling indicated R252L causes significant active site residue shifts, while D60N may affect an outer loop.

Conclusions:

• GSPD-1 serves as a viable model for human G6PD deficiency research.
• The C. elegans model allows for potential in vivo studies of G6PD deficiency treatments.