Submitted to: Phytochemistry Letters
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 16, 2013
Publication Date: May 1, 2013
Citation: Bohnert, M., Hans-Martin, D., Gibson, D.M., Krasnoff, S., Hoffmeister, D. 2013. The fusarin analogue NG-391 impairs nucleic acid formation in K-562 leukemia cells. Phytochemistry Letters. 6:189-192. Interpretive Summary: Fungi in the genus Metarhizium can infect many insect pests, making them useful for development as insect biological control agents. For microbial strains already in use or under evaluation as biocontrol agents, it is especially important to identify all possible bioactive chemistries that are present in the organism, both from a regulatory standpoint as well as to further understand how various products serve the producing organism. In this paper, we further explored the biological activity of NG391, a compound we previously isolated and identified as a mutagenic toxin. This study explains the biological activity to include cytotoxic activity through a potent effect on nucleic acid biosynthesis. This finding does increase the need to develop a more complete understanding of the factors that regulate expression of these products and especially as they relate to biocontrol activity.
Technical Abstract: The clavicipitaceous fungus Metarhizium robertsii produces the fusarin-like mycotoxin NG-391. We report on the biological effects of NG-391 on K-562 human cancer cells, obtained with radionuclide incorporation assays, along with nucleosome release and caspase assays, respectively. Our data suggests that NG-391 does not induce caspase-dependent apoptosis, but interferes with nucleic acid biosynthesis in K-562 human cancer cells, while translation remains unaffected.