Bacterial type I modular polyketide synthases (PKSs) are complex, multifunctional enzymes that synthesize structurally diverse and medicinally relevant natural products. Given their modular organization, the manipulation of type I PKSs holds tremendous promise for the generation of novel macrolide antibiotics that are not easily accessible by standard chemical synthetic approaches. To fully harness this potential, however, a thorough evaluation of a variety of PKS systems is needed. To this end, the experiments described within this proposal seek to interface chemical synthesis with rigorous kinetic analysis and structural biology in an effort to enhance our understanding of specificity and catalysis of the pikromycin PKS system. In addition to providing detailed information regarding the kinetics of individual PKS modules, this work will also begin to uncover substrate specificity differences between the pikromycin and erythromycin (DEBS) PKS systems. Furthermore, a detailed understanding of the specificity of the pikromycin thioesterase domain will be achieved via x-ray co-crystallization studies. ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
5F32GM075641-02
Application #
7222730
Study Section
Special Emphasis Panel (ZRG1-F04A-D (20))
Program Officer
Marino, Pamela
Project Start
2006-05-01
Project End
2008-04-30
Budget Start
2007-05-01
Budget End
2008-04-30
Support Year
2
Fiscal Year
2007
Total Cost
$48,796
Indirect Cost
Name
University of Michigan Ann Arbor
Department
Pharmacology
Type
Schools of Pharmacy
DUNS #
073133571
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109
Mortison, Jonathan D; Kittendorf, Jeffrey D; Sherman, David H (2009) Synthesis and biochemical analysis of complex chain-elongation intermediates for interrogation of molecular specificity in the erythromycin and pikromycin polyketide synthases. J Am Chem Soc 131:15784-93
Kittendorf, Jeffrey D; Sherman, David H (2009) The methymycin/pikromycin pathway: a model for metabolic diversity in natural product biosynthesis. Bioorg Med Chem 17:2137-46
Kittendorf, Jeffrey D; Beck, Brian J; Buchholz, Tonia J et al. (2007) Interrogating the molecular basis for multiple macrolactone ring formation by the pikromycin polyketide synthase. Chem Biol 14:944-54
Akey, David L; Kittendorf, Jeffrey D; Giraldes, John W et al. (2006) Structural basis for macrolactonization by the pikromycin thioesterase. Nat Chem Biol 2:537-42
Giraldes, John W; Akey, David L; Kittendorf, Jeffrey D et al. (2006) Structural and mechanistic insights into polyketide macrolactonization from polyketide-based affinity labels. Nat Chem Biol 2:531-6
Kittendorf, Jeffrey D; Sherman, David H (2006) Developing tools for engineering hybrid polyketide synthetic pathways. Curr Opin Biotechnol 17:597-605