Presenter Status

Undergraduate Student, Department of Chemistry and Biochemistry

Second Presenter Status

Assistant Professor, Department of Chemistry

Third Presenter Status

Graduate Student, Department of Chemistry

Preferred Session

Poster Session

Start Date

25-10-2019 2:00 PM

Presentation Abstract

In the production of commodity chemicals through microbial synthesis, the use of renewable sugars as a raw material is increasingly common. However, this generates competition between its use in the chemical industry and the food industry. Therefore, developing alternative biosynthetic pathways involving other renewable feedstocks to replace starch-derived feedstocks is crucial. CgX, a tautomerase native to Corynebacterium glutamicum, catalyzes the hydration and subsequent decarboxylation of acetylenecarboxylic acid (ACA), a compound that can be produced from methane gas and carbon dioxide, both abundant greenhouse gases. The products formed from the CgX (wild-type)-catalyzed reaction of ACA results in a mixture of malonic semialdehyde and acetaldehyde. Six amino acids have been identified as the catalytic residues. The research project involves monitoring the formation of products and building product profiles, in addition to kinetic characterization, of various mutants of CgX. In addition to the six critical amino acids, Q5 site-directed mutagenesis will be used to generate other mutants of CgX. In this presentation, the synthesis methodology and the products formed, as determined by NMR, will be discussed. In addition, results from kinetic studies using coupled enzyme assay will be presented.

Acknowledgments

This material is based upon work supported by the National Science Foundation under Grant No. (CHE-1851776). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Many thanks to Professor Karen Draths and Amaya Sirinimal for their critical role and support and to Michigan State University Department of Chemistry for this opportunity.

COinS
 
Oct 25th, 2:00 PM

P-20 Characterization of CgX Tautomerase and Mutants with Acetylenecarboxylic Acid

In the production of commodity chemicals through microbial synthesis, the use of renewable sugars as a raw material is increasingly common. However, this generates competition between its use in the chemical industry and the food industry. Therefore, developing alternative biosynthetic pathways involving other renewable feedstocks to replace starch-derived feedstocks is crucial. CgX, a tautomerase native to Corynebacterium glutamicum, catalyzes the hydration and subsequent decarboxylation of acetylenecarboxylic acid (ACA), a compound that can be produced from methane gas and carbon dioxide, both abundant greenhouse gases. The products formed from the CgX (wild-type)-catalyzed reaction of ACA results in a mixture of malonic semialdehyde and acetaldehyde. Six amino acids have been identified as the catalytic residues. The research project involves monitoring the formation of products and building product profiles, in addition to kinetic characterization, of various mutants of CgX. In addition to the six critical amino acids, Q5 site-directed mutagenesis will be used to generate other mutants of CgX. In this presentation, the synthesis methodology and the products formed, as determined by NMR, will be discussed. In addition, results from kinetic studies using coupled enzyme assay will be presented.