Discovery and application of halogenases for medicinal chemistry
openNIGMS - National Institute of General Medical Sciences
Project Summary
Halogen atoms (F–, Cl–, Br–, and I–) are incredibly versatile components of both naturally produced and
synthetic compounds. Over half of the pharmaceuticals on the market in the United States contain at least
one halogen atom, and likely many more compounds involve halogen atoms in their synthesis. Chemical
methods for installing halogen atoms typically generate one or more undesired side products and require
reagents that have adverse effects for human and environmental health. Methods improving both
halogenation selectivity and sustainability are therefore highly desired. My lab approaches these general
needs by studying enzymes to complement synthetic chemical methods. Specifically, we focus on
halogenases capable of installing halogen atoms onto organic compounds with precise selectivity in an
environmentally-benign manner. In the area of medicinal chemistry, halogenases have the potential to
transform the landscape of environmentally-conscious catalysis, but shortcomings related to enzyme
stability, scope of substrate preference, and reaction kinetics have limited their broad application thus far.
To combat these known limitations, my group combines bioinformatics, natural product biosynthetic logic,
and enzymology to identify novel enzymes in publicly available genomic data with biocatalytic potential.
Using these techniques, we have identified a new family of halogenases that is phylogenetically unrelated
to known halogenases and possesses superior kinetic properties, enhanced stability, and broad substrate
scope. Within this family exist two distinct chemoselectivity preferences where one subsection of the family
targets indole-containing molecules such as the amino acid L-tryptophan and the other selectively installs
halogen atoms onto terminal alkynes to generate haloalkynes, a reaction that was previously unknown in
enzyme chemistry. The initial discovery of these powerful biocatalysts inspires the focus of this proposal,
which places emphasis on expanding our fundamental understanding of the biochemistry of this new
halogenase family and developing both scalable and high throughput biocatalytic platforms to leverage the
potential of these enzymes in medicinal chemistry. In the period of the next five years, we aim to break new
ground in halogenation chemistry and biocatalysis, develop robust and generalizable methodologies to apply
to other enzyme systems in our lab, and identify the next phase of biocatalytic innovation in our program
through natural product discovery. Through the highly interdisciplinary research described in this proposal,
members of the Lukowski lab are trained in enzymology, natural products chemistry, biosynthesis, analytical
chemistry, biocatalysis, organic chemistry, microbiology, synthetic biology, marine science, and
bioinformatics, enabling challenging problems to be tackled and preparing the next generation of
researchers for careers in industry, academia, government, and the private sector.
Up to $424K
health research