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Leora awarded NSF GRFP

Leora Duong awarded NSF GRFP fellowship for her work relating to Microbial Biology and Biophysics. Congratulations!!!

Leora picked for talk at UCI Immunology Fair

Leora is giving a talk at today’s UCI Immunology Fair around 10:40am “A novel antimicrobial approach: histones and antimicrobial peptides”. Agenda here: http://www.immunology.uci.edu/immunology-fair/agenda.asp

In press @ Nature Comm. “Mammalian histones facilitate antimicrobial synergy by disrupting the bacterial proton gradient and chromosome organization”

Tory’s paper in press @ Nature Comm. “Mammalian histones facilitate antimicrobial synergy by disrupting the bacterial proton gradient and chromosome organization”. Her paper reports a new mechanism that gives rise to antibiotic synergy. https://www.nature.com/articles/s41467-020-17699-z#article-info

First proposed as antimicrobial agents, histones were later recognized for their role in condensing chromosomes. Histone antimicrobial activity has been reported in innate immune responses. However, how histones kill bacteria has remained elusive. The co-localization of histones with antimicrobial peptides (AMPs) in immune cells suggests that histones may be part of a larger antimicrobial mechanism in vivo. Here we report that histone H2A enters E. coli and S. aureus through membrane pores formed by the AMPs LL-37 and magainin-2. H2A enhances AMP-induced pores, depolarizes the bacterial membrane potential, and impairs membrane recovery. Inside the cytoplasm, H2A reorganizes bacterial chromosomal DNA and inhibits global transcription. Whereas bacteria recover from the pore-forming effects of LL-37, the concomitant effects of H2A and LL-37 are irrecoverable. Their combination constitutes a positive feedback loop that exponentially amplifies their antimicrobial activities, causing antimicrobial synergy. More generally, treatment with H2A and the pore-forming antibiotic polymyxin B completely eradicates bacterial growth.

KEYWORDS: Mammalian histones, neutrophil extracellular traps, lipid droplets, bacterial chromosomal organization, antimicrobial synergy, host-microbe, proton gradient

Calvin, Frank, and Jennifer graduate

Congratulations to the class of 2020. Calvin Trinh, Frank Ramirez, and Jennifer Poo are graduating. Calvin and Jennifer will be working towards …

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