Related Experiment Video
Updated: Jul 7, 2026

Detection of Inflammasome Activation and Pyroptotic Cell Death in Murine Bone Marrow-derived Macrophages
Published on: May 21, 2018
The effects of anthrax lethal factor on the macrophage proteome: potential activity on nitric oxide synthases
Joungmok Kim1, Haechul Park, Jang Myung-Hyun
1Department of Chemistry, College of Natural Sciences, Hanyang University, Seoul 133-791, Republic of Korea.
Abstract:
Anthrax lethal factor (LeTx) is a critical virulence factor in toxin-challenged cells, as lethal factor (LF) cleaves mitogen-activated protein kinase kinases (MKKs), inhibiting their activity. The physiological importance of this cleavage for macrophage cytolysis remains unclear, because similar proteolysis has been also observed in LeTx-resistant macrophages. Here, we analyzed in vitro proteomic profiles of Raw264.7 lysates treated with LF. In our experiments, neuronal NO synthase (nNOS) was found to be a fragment, suggesting that LF may act on nNOS cleavage. A similar cleavage of nNOS was shown in LeTx-challenged HEK293 cells expressing nNOS by a transient transfection. However, the cleavage site on nNOS is a unique leader sequence among the NOS family and this LF-mediated cleavage was not observed in iNOS, a major NOS isoform for anti-bactericidal NO production, even though NO level in LeTx-challenged cells was dramatically reduced. Our findings suggest that LF is directly capable of cleaving cellular protein(s) other than MKKs, and that these actions potentiate to promote the cytotoxic mechanisms of anthrax.
More Related Videos
06:34Isolation and In vitro Culture of Bone Marrow-Derived Macrophages for the Study of NO-Redox Biology
Published on: May 31, 2022
07:55A Macrophage Reporter Cell Assay to Examine Toll-Like Receptor-Mediated NF-kB/AP-1 Signaling on Adsorbed Protein Layers on Polymeric Surfaces
Published on: January 7, 2020
Related Concept Videos
Inhalation Anthrax
Bacterial Toxins
Nitric Oxide Signaling Pathway
NF-κB-dependent Signaling Pathway
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...