Overexpression, purification, and characterization of MmgD from Bacillus subtilis strain 168.

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Rejwi Acharya (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/
Advisor
Jason Reddick

Abstract: Bacillus subtilis, a rod shaped gram-positive bacterium, is highly studied because of its capability of forming endospores when there is an inadequate supply of nutrients. Despite the lack of nutrients in the environment, this microorganism has to be able to generate energy to support sporulation. One operon expressed during sporulation is the mother cell metabolic (mmg) operon. The six open reading frames (ORFs) of the mmg operon are mmgABCDE and yqiQ. The first three genes are homologs of fatty acid metabolism enzymes and the last three are expected to encode part of the methyl citric acid cycle, which is a metabolic pathway that processes propionyl-CoA. In the absence of glucose, the preferred carbon source, this organism most likely makes use of other carbon sources, such as fatty acids and/ or propionates to fuel sporulation. Based on sequence homology the function of mmgD is similar by sequence to citrate synthase III. MmgD has been successfully cloned, overexpressed, and the purified MmgD enzyme from Bacillus subtilis strain 168 has demonstrated citrate synthase and methyl citrate synthase characteristics. MmgD showed slight preference for propionyl-CoA over acetyl-CoA. Besides activity determination and substrate preference, product formations of this enzyme have also been validated via 1H-proton NMR.

Additional Information

Publication
Thesis
Language: English
Date: 2009
Keywords
B. subtilis, Citrate synthase, Methylcitrate synthase, Sporulation
Subjects
Bacillus subtilis $x Genetics.
Bacillus subtilis $x Metabolism $x Genetic aspects.
Enzymes.