Arsenic is classified as a carcinogen by the U.S, Environmental Protection Agency. More recently arsenic trioxide (Trisenox) has been approved for use as a chemotherapeutic agent for the treatment of acute promyelocytic leukemia. The goal of this research is the elucidation of the molecular mechanisms in members of two families of arsenate reductases. The arsenate (As(V)) reductase found in many bacteria is typified by the ArsC enzyme encoded by the (ars) operon found on the clinically-isolated E. coli resistance plasmid R773. Eukaryotes have pathways for arsenic detoxification that arose through convergent evolution. The ACR2 gene of Saccharomyces cerevisiae encodes an arsenate reductase required for arsenate resistance in yeast but is not an ArsC homologue.
Specific aims i nclude: 1) Structure/function relationships in the arsenate reductases: Residues in the E. coli ArsC and S. cerevisiae Acr2p involved in function will be identified such as anion binding sites and residues involved in catalysis. 2) Interaction of ArsC with glutaredoxin: Glutaredoxin 2 (Grx2) is the most efficient hydrogen donor for ArsC. The contact points between Grx2 and ArsC will be determined by a combination of biochemical and genetic approaches including crystallography, NMR and florescence spectroscopy. Similar methods will be applied to the interaction of Acr2p and glutaredoxin. 3) Characterization of the Leishmania major LmAcr2p arsenate reductase: As one consequence of the war on terrorism American soldiers are more and more frequently returning from Iraq with """"""""Baghdad boil"""""""" -better known as leishmaniasis. The first-drug for treatment of this re-emerging infectious disease is the pentalvalent antimonial drug Pentostam, and Pentostam resistance is becoming a major clinical problem. We propose that LmAcr2p plays a role biotransformation of Pentostam to its active form by reducing Sb(V) to Sb(III). 4) The structure two eukaryotic arsenate reductases will be determined: The structure two eukaryotic arsenate reductases, ScAcr2p from S. cerevisiae and LmAcr2p from L. major will be determined using x-ray crystallography. These proteins can be produced in large amounts and are easily purified for crystallization trials. LmAcr2p and the G83A mutant of ScAcr2p are both small monomeric proteins that are good candidates for structural studies by NMR spectroscopy.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM052216-11
Application #
7151175
Study Section
Microbial Physiology and Genetics Subcommittee 2 (MBC)
Program Officer
Chin, Jean
Project Start
1995-04-01
Project End
2008-11-30
Budget Start
2006-12-01
Budget End
2007-11-30
Support Year
11
Fiscal Year
2007
Total Cost
$233,922
Indirect Cost
Name
Wayne State University
Department
Biochemistry
Type
Schools of Medicine
DUNS #
001962224
City
Detroit
State
MI
Country
United States
Zip Code
48202
Chen, Jian; Li, Jiaojiao; Jiang, Xuan et al. (2017) Conserved cysteine residues determine substrate specificity in a novel As(III) S-adenosylmethionine methyltransferase from Aspergillus fumigatus. Mol Microbiol 104:250-259
Chen, Jian; Nadar, Venkadesh Sarkarai; Rosen, Barry P (2017) A novel MAs(III)-selective ArsR transcriptional repressor. Mol Microbiol 106:469-478
Chen, Jian; Bhattacharjee, Hiranmoy; Rosen, Barry P (2015) ArsH is an organoarsenical oxidase that confers resistance to trivalent forms of the herbicide monosodium methylarsenate and the poultry growth promoter roxarsone. Mol Microbiol 96:1042-52
Rosen, Barry P; Liu, Zijuan (2009) Transport pathways for arsenic and selenium: a minireview. Environ Int 35:512-5
Mukhopadhyay, Rita; Bisacchi, Davide; Zhou, Yao et al. (2009) Structural characterization of the As/Sb reductase LmACR2 from Leishmania major. J Mol Biol 386:1229-39
Bhattacharjee, Hiranmoy; Rosen, Barry P; Mukhopadhyay, Rita (2009) Aquaglyceroporins and metalloid transport: implications in human diseases. Handb Exp Pharmacol :309-25
Sundaram, Sabarinath; Rathinasabapathi, Bala; Ma, Lena Q et al. (2008) An arsenate-activated glutaredoxin from the arsenic hyperaccumulator fern Pteris vittata L. regulates intracellular arsenite. J Biol Chem 283:6095-101
Duan, Gui-Lan; Zhou, Yao; Tong, Yi-Ping et al. (2007) A CDC25 homologue from rice functions as an arsenate reductase. New Phytol 174:311-21
Bisacchi, Davide; Zhou, Yao; Rosen, Barry P et al. (2006) Crystallization and preliminary crystallographic characterization of LmACR2, an arsenate/antimonate reductase from Leishmania major. Acta Crystallogr Sect F Struct Biol Cryst Commun 62:976-9
Zhou, Yao; Bhattacharjee, Hiranmoy; Mukhopadhyay, Rita (2006) Bifunctional role of the leishmanial antimonate reductase LmACR2 as a protein tyrosine phosphatase. Mol Biochem Parasitol 148:161-8

Showing the most recent 10 out of 47 publications