Related Experiment Videos
Glutamate synthesis in Streptomyces coelicolor
1Department of Microbiology, Boston University School of Medicine, Massachusetts 02118.
Journal of Bacteriology
|May 1, 1989
Summary
Glutamate synthase (GOGAT) and glutamate dehydrogenase (GDH) are key for glutamate synthesis in Streptomyces coelicolor. GOGAT deficiency necessitates glutamate supplementation for growth on certain nitrogen sources, while dual GOGAT/GDH deficiency requires it universally.
Area of Science:
- Microbiology
- Biochemistry
- Molecular Biology
Background:
- Glutamate synthesis is crucial for microbial growth and nitrogen metabolism.
- Streptomyces coelicolor utilizes multiple pathways for glutamate production.
Purpose of the Study:
- To investigate the roles of glutamate synthase (GOGAT) and glutamate dehydrogenase (GDH) in Streptomyces coelicolor glutamate synthesis.
- To characterize the growth phenotypes of mutants deficient in GOGAT and/or GDH.
Main Methods:
- Enzyme activity assays for GOGAT and GDH in cell extracts.
- Growth studies of wild-type and mutant strains on various nitrogen sources.
- Genetic mapping of mutations.
Main Results:
- GDH activity was highest with high ammonium concentrations.
- GOGAT activity decreased with readily available glutamate.
- GOGAT-deficient mutants required glutamate for growth on specific nitrogen sources, unlike wild-type.
- Mutants lacking both GOGAT and GDH required glutamate for growth on all tested media.
- glt mutations linked to hisA1; gdh-5 mapped between proA1 and uraA1.
Conclusions:
- GOGAT and GDH play distinct but essential roles in glutamate biosynthesis in S. coelicolor.
- The specific nitrogen source influences the reliance on GOGAT versus GDH.
- Understanding these pathways is vital for manipulating nitrogen metabolism in Streptomyces.