Enzymatic Hydrolytic Dehalogenation of Chlorinated Aromatic Compounds

NSF Award Search · 01002526DB NSF RESEARCH & RELATED ACTIVIT · $555,000 · view on nsf.gov ↗

Abstract

With the support of the Chemistry of Life Processes program in the Division of Chemistry, Professor Holz from the Colorado School of Mines will investigate the enzymatic biodegradation of the fungicide chlorothalonil and the herbicide atrazine, two halogenated aromatic hydrocarbons, which are highly toxic and carcinogenic. Their removal is challenging because they are chemically stable, resistant to degradation, and lipophilic. Nevertheless, some enzymes can catalyze their degradation to less-toxic analogs. The project focuses on understanding the mechanism of enzymatic biodegradation. The project will also provide exceptional training for undergraduate and graduate-level scientists and serve as the basis for community engagement activities. This research project seeks to gain molecular-level insights into two Zn(II)-dependent hydrolytic dehalogenases, namely a chlorothalonil dehalogenase (Chd) and a triazine hydrolase (TrzN). These enzymes degrade chlorothalonil and atrazine, respectively, to their corresponding less-toxic alcohol derivatives. The catalytic mechanisms of both Chd and TrzN will be examined using an interdisciplinary approach that includes kinetics, spectroscopic, biochemical, computational, X-ray methods, and biomaterial synthesis. Three important unanswered questions will be addressed: (i) What is the allosteric and structural influence on Chd activity, including its impact on active site residues that are catalytically important?, (ii) Can biomaterials

Key facts

NSF award ID
2452699
Awardee
Colorado School of Mines (CO)
SAM.gov UEI
JW2NGMP4NMA3
PI
Richard C Holz
Primary program
01002526DB NSF RESEARCH & RELATED ACTIVIT
All programs
Estimated total
$555,000
Funds obligated
$555,000
Transaction type
Standard Grant
Period
09/01/2025 → 08/31/2028