Centennial Honors College
Western Illinois University
Undergraduate Research Day 2014
Poster Presentation
Cloning of a Putative L-3-hydroxyacyl-CoA Dehydrogenase from Micrococcus
Luteus WIUJH20
Antoinee Watson-Taylor
Faculty Mentors: Lisa Wen and Jenq-Kuen Huang
Chemistry
Enzymes are biological catalysts that carry out chemical reactions in all living
organisms. Thus, enzymes play important roles in maintaining health and vitality. The
present research is aimed at understanding how enzyme works by studying two
enzymes: secondary alcohol dehydrogenase (2°-ADH) and L-3-hydroxyl-CoA
dehydrogenase (L-3-HAD). Alcohol dehydrogenases are enzymes that break down
alcohols and catalyze interconversion between alcohols and aldehydes or ketones. L-3HADs are enzymes involved in the fatty acid oxidation pathway. Through the amino acid
sequences alignment study of 2°-ADH from Micrococcus luteus WIUJH20 (M.
luteusWIUJH20) with those in the Protein Database, it was discovered that the 2°-ADH
has 89% sequence identity with the annotated L-3-HAD from M. luteus NCTC2665.
However, we have ruled out that the annotated L-3-HAD doesn’t belong to L-3-HADs
family by kinetics studies of the purified 2°-ADH. The two enzymes are different in their
selection of reactants/substrates. Therefore, the L-3-HAD and 2°-ADH are excellent
model systems for studying structure-function relationship of the enzymes and probing
the amino acid residues within the enzymes that are responsible for achieving such
specificity. Such study requires production of large amounts of each enzyme obtained
from M. luteusWIUJH20 to make comparison significant.
The short-term objective of this research is to isolate the gene encoding L-3-HAD from
M. luteus WIUJH20 by molecular cloning approach to produce large quantity of L-3HAD. The long-term goal of this project is to understand how enzymes react specifically
to their substrates. This poster presentation will include strategies for the gene cloning
and preliminary results.