Department of Communication & Public Affairs

University Affairs

Date: 01-14-08
Name: Zenaida Mendez
Phone: (973) 972-5000
Email: mendezze@umdnj.edu

UMDNJ Study Results in Conclusive Proof of Regulated Deployment of a Toxin Gene for Developmental Programmed Cell Death in Bacteria

NEW BRUNSWICK – A study headed by a UMDNJ–Robert Wood Johnson Medical School researcher has rendered conclusive proof, for the first time, that a toxin produced within certain bacterium kills the bacterium’s cells.

By identifying the genes involved, Masayori Inouye’s lab clearly has demonstrated programmed cell death in bacteria. The discovery could potentially lead to development of antibiotics for Mycobacterium tuberculosis, Staphylococcus and other pathogens with similar toxins, said Inouye, Professor in the Department of Biochemistry at UMDNJ–Robert Wood Johnson Medical School.

A paper outlining his lab’s findings, “MazF, an mRNA interferase, mediates programmed cell death during multicellular Myxococcus development,” appears in the Jan. 11 online issue of Cell. Visit Requirement for a toxin in bacterial development at www.cell.com to view the article.

In this study, Inouye’s lab looked at Myxococcus xanthus, a bacterium displaying multi-cellular development during which 80 percent of the cells undergo obligatory cell death.

This bacterium contains a toxin gene (mazF-mx) encoding an mRNA interferase cleaving mRNAs. Deletion of the toxin gene eliminated the obligatory cell death during development, causing a dramatic reduction of spore formation, Inouye reports.

“When we say toxins, people think they are excreted out of bacteria, killing surrounding cells,” Inouye said. “The toxin we have found is produced inside the bacterium and kills itself.”

“If we could figure out how to induce these toxins, then we may be able to come up with new types of antibiotics to suppress these pathogens,” Inouye explained. “That’s the direction we’ve been working on in this lab.”

This discovery is the latest of Masayori Inouye’s science contributions, which include membrane biogenesis, structural and functional studies of histidine kinases, propeptide (intramolecular chaperone) mediated protein folding (related to Mad Cow disease), discovery of bacterial reverse transcriptases and multicopy single stranded DNA (msDNA), and the cold shock response and adaptation in E. coli.

His research lab interests include molecular mechanisms of cellular adaptation to various stresses and growth conditions; cellular adaptation to low temperature; Protein folding; and cell division regulated by a GTP-binding protein in E. coli.

To interview Dr. Masayori Inouye, contact Zenaida Mendez at (973) 972-5000.

UMDNJ is the nation’s largest free-standing public health sciences university with more than 5,700 students attending the state's three medical schools, its only dental school, a graduate school of biomedical sciences, a school of health related professions, a school of nursing and a school of public health on five campuses. Annually, there are more than two million patient visits at UMDNJ facilities and faculty practices at campuses in Newark, New Brunswick/Piscataway, Scotch Plains, Camden and Stratford. UMDNJ operates University Hospital, a Level I Trauma Center in Newark, and University Behavioral HealthCare, a statewide mental health and addiction services network.

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