|SATHOFF, ANDREW - University Of Minnesota|
|Samac, Deborah - Debby|
|SCHMITT, TONY - University Of Minnesota|
|CARTER, CLAY - University Of Minnesota|
Submitted to: Mycological Society of America
Publication Type: Abstract Only
Publication Acceptance Date: 4/15/2017
Publication Date: 7/16/2017
Citation: Sathoff, A., Samac, D.A., Schmitt, T., Carter, C. 2017. Antimicrobial activity of Brassica nectar lipid transfer protein. Mycological Society of America. Athens, Georgia. July 16-19, 2017.
Technical Abstract: Antimicrobial peptides (AMPs) provide an ancient, innate immunity conserved in all multicellular organisms. In plants, there are several large families of AMPs defined by sequence similarity. The nonspecific lipid transfer protein (LTP) family is defined by a conserved signature of eight cysteines and has a compact structure with a lipid-binding hydrophobic cavity. The antimicrobial activity of LTPs varies greatly among plant species. A LTP from Brassica nectar was tested for antimicrobial activity. In a 96-well microplate, each well contained half strength potato dextrose broth, approximately 2000 spores, and concentrations of LTP peptide up to 300 ug/mL in a total volume of 100 uL. After 48 hours of incubation at 25 degrees C in the dark, absorbance of the wells was measured at 595 nm on a microplate reader to quantify the inhibition of fungal growth. The amount of LTP needed to inhibit growth of pathogen strains by 50% (IC50) was calculated. This Brassica LTP was most effective against Alternaria and Colletotrichum trifolii with IC50 values of 3.70 uM and 2.97 uM, respectively. The activity of the Brassica LTP at such low uM values indicates that it is a potent defense protein. These results suggest that transgenic expression of LTPs has the potential to lead to improved broad-spectrum disease resistance.