Shaleen Korch, PhD

Associate Professor


Midwestern University
Arizona College of Osteopathic Medicine
Pharmacology
Agave Hall 214-1
19555 N 59th Ave
Glendale, AZ 85308

Office: (623)572-3708
e-mail: skorch@midwestern.edu

EDUCATION

BSc Biology/Biochemistry University of Winnipeg  1999
PhD Microbiology and Immunology University of North Dakota 2005

RESEARCH SUMMARY

Prokaryotic adaptive responses to energy depletion.

My lab is interested in characterizing the adaptive response of E. coli to ATP depletion, which is induced by a synthetic ATP-binding protein, DX. This project is in collaboration with Dr. John Chaput, an established Synthetic Biologist at Arizona State University, who synthesized the DX protein de novo. Using DX as a molecular tool to induce energy deprivation, we have discovered a novel stress response in E. coli that includes the development of large lipid bodies (endoliposomes), cellular filamentation and entrance into a viable-but-non-culturable state - all correlated with the depletion of intracellular ATP.

Toxin:antitoxin modules in Mycobacterium tuberculosis.

Mycobacterium tuberculosis, the causative agent of tuberculosis disease, has the unique ability to persist for long periods of time in its host as a latent infection. Despite all efforts, the molecular switch(es) governing M. tuberculosis' growth rate are still unknown. Toxin-antitoxin (TA) modules have the potential to act as master regulators of M. tuberculosis growth and my lab is interested in determining the role(s) of the relBE TA family in Mycobacterium tuberculosis persistence. We have determined that relBE are stress-responsive modules that act as mRNA interferases, resulting in growth inhibition in M. tuberculosis. Our current focus is on the regulation of the M. tuberculosis relBE family, at the level of transcription and toxin function.

Selected Publications

ATP sequestration by a synthetic ATP-binding protein leads to novel phenotypic changes in Escherichia coli.

Korch SB, Stomel JM, León MA, Hamada MA, Stevenson CR, Simpson BW, Gujulla SK, Chaput JC. ACS Chem Biol. 2013 Feb 15;8(2):451-63. doi: 10.1021/cb3004786.

Three Mycobacterium tuberculosis Rel toxin-antitoxin modules inhibit mycobacterial growth and are expressed in infected human macrophages.

Korch SB, Contreras H, Clark-Curtiss JE. J Bacteriol. 2009 Mar;191(5):1618-30. doi: 10.1128/JB.01318-08.

Ectopic overexpression of wild-type and mutant hipA genes in Escherichia coli: effects on macromolecular synthesis and persister formation.

Korch SB, Hill TM.

J Bacteriol. 2006 Jun;188(11):3826-36. PMID:16707675

Characterization of the hipA7 allele of Escherichia coli and evidence that high persistence is governed by (p)ppGpp synthesis.

Korch SB, Henderson TA, Hill TM.

Mol Microbiol. 2003 Nov;50(4):1199-213. PMID:14622409