Grosmannia clavigera is a widespread pathogen of coniferous trees and a common symbiotic of bark beetles (MPB, Dendroctonus ponderosae). G. clavigera is known as blue stain fungus because of the characteristic blue-gray stain that it gives to infected wood. Over the course of an infection, G. clavigera spreads throughout the wood of the host tree. If left unchecked, G. clavigera infections will eventually disrupt the transport of nutrients and water, which will result in the death of the host tree. G. clavigera can also prevent the flow of sap, which drastically lowers the host tree’s resistance to infestation from bark beetles, who, in turn, carry spores and help propagate the fungus. The Pine beetle and its associated symbiotic fungus are the cause of a large wipeout of pines across North America. The USDA reported an impact on tree life spanning across 900 miles of trail in Colorado and Wyoming and a loss of 18 million hectares of Pine forest across western Canada.
To investigate how G. clavigera (i) survives under toxic conditions of monoterpenes found in trees’ bark as a defense mechanism and (ii) which genes are involved in the removal and consumption of monoterpenes as a carbon source, G. clavigera wild-type and G. clavigera ABC transporter mutant were grown on two media: malt extract agar (MEA), an enriched medium containing the full nutrient sources needed for successful fungal growth; and yeast nitrogen base (YNB), a minimal medium lacking both the carbon source and amino acids necessary for fungal growth. Both of these media were used to grow G. clavigera with and without the addition of monoterpenes.
It was found in the absence of common nutrients, the fungus is capable of using monoterpenes as an energy source. The up-regulation of enzymes involved in beta-oxidation of fatty acids in mitochondria suggest that the metabolism of monoterpenes into an energy source relies heavily on the mitochondria. The G. clavigera project shows that the T-Bioinfo platform allows analysis of transcriptome data in poorly understood genomes. The T-Bioinfo Platform assists in annotation of the genome as well as allowing for the identification of biochemical mechanisms.