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Visualization of ATP Synthase Dimers in Mitochondria by Electron Cryo-tomography
Published on: September 14, 2014
Anthranilate synthase subunit organization in Chromobacterium violaceum.
C A Carminatti1, I L Oliveira, D O S Recouvreux
1Departamento de Engenharia Química e Engenharia de Alimentos, Universidade Federal de Santa Catarina, Florianópolis, SC, Brasil. claudimir@intelab.ufsc.br
Genetics and Molecular Research : GMR
|October 25, 2008
Summary
Chromobacterium violaceum uses anthranilate synthase (AS) with alpha (TrpE) and beta (PabA) subunits for violacein production. Bioinformatics analysis identified catalytic and regulatory sites within these AS subunits.
Area of Science:
- Biochemistry
- Molecular Biology
- Bioinformatics
Background:
- Tryptophan is essential for protein synthesis and cellular growth.
- Chromobacterium violaceum synthesizes violacein, a pharmacologically relevant secondary metabolite, using tryptophan.
- The tryptophan pathway in C. violaceum involves anthranilate synthase (AS), an enzyme complex.
Purpose of the Study:
- To analyze the organization and structure of anthranilate synthase (AS) protein subunits from Chromobacterium violaceum.
- To identify the catalytic and regulatory sites within the AS subunits.
- To build protein models for the AS subunits.
Main Methods:
- Bioinformatics tools were employed for analysis.
- Molecular masses of AS subunits were calculated.
- Restraint-based homology modeling was used to build protein models, utilizing the AS enzyme from Salmonella typhimurium (PDB ID 1I1Q).
Main Results:
- Anthranilate synthase (AS) in C. violaceum is composed of alpha (TrpE) and beta (PabA) subunits, consistent with experimental data.
- Catalytic sites were identified involving both TrpE and PabA subunits.
- The TrpE subunit was identified as contributing to the allosteric site.
Conclusions:
- The study elucidates the subunit composition and functional sites of anthranilate synthase in Chromobacterium violaceum.
- Bioinformatic analysis provides a structural basis for understanding violacein biosynthesis.
- The identified protein models can aid further research into AS function and enzyme engineering.
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