Fatty Acid Kinase Structure and Function Relationships

Hannah Gross, Brian Weinzirl, Maxwell Bachochin, Brittany Dobrowski, and Robert Barber, Department of Biological Sciences, University of Wisconsin-Parkside, Room 375 Greenquist Hall, 900 Wood Rd, Kenosha, WI 53141-2000

Assorted short chain and medium chain fatty acids are end products of dietary fiber fermentation by intestinal microbiota. These fatty acids are known to exert multiple beneficial effects on mammalian energy metabolism, such as being a valuable carbon and energy source for colonocytes as well as boosting immune responses. Understanding the enzymes involved in the production and utilization of fatty acids is important for deciphering these beneficial effects and the underlying metabolic principles among gut microbiota. One pathway for fatty acid metabolism relies on the concerted efforts of two distinct enzymes, a fatty acid kinase and an acyltransferase. Our laboratory is examining a variety of natural enzyme variants of fatty acid kinases in an effort to understand nuances in substrate specificity among disparate enzymes. Biochemical and computational analyses have been performed for fatty acid kinases from Rhodobacter sphaeroides, Desulfovibrio vulgaris str. Hildenborough, and Bacteroides vulgatus, which exhibit amino acid substitutions predicted to be involved in fatty acid binding. In vitro studies using purified enzymes, which have been heterologously produced in Escherichia coli, have determined kinetic constants for a variety of fatty acid substrates among these different enzymes, as well as produced interesting results regarding substrate protection and thermostability. In silico protein structure model building along with computational ligand binding studies have contributed substantial insight regarding our interpretation of these biochemical results. In particular, identification of amino acids contributing to oligomerization and surface loops involved in substrate binding has generated an improved view of the acyl-binding pocket of these enzymes as well as enhanced perspective concerning the evolution of their novel metabolic roles within these bacteria.

Additional Abstract Information

Presenter: Hannah Gross

Institution: University of Wisconsin - Parkside

Type: Poster

Subject: Biology

Status: Approved

Time and Location

Session: Poster 3
Date/Time: Mon 4:30pm-5:30pm
Session Number: 3162