Finding a cure for aspergillosis
Mitogen-activated protein kinase (MAPK) signalling pathways are important for maintaining cell wall integrity in A. fumigatus. Research has shown that three protein kinases play a key role here. Protein kinases are reversibly activated through phosphorylation and are essential in signalling pathways and crosstalk interactions in fungi. Using ontology classification of protein phosphatases in A. fumigatus, CELLWALLPATH researchers investigated cell wall compensatory pathways. Previous research has shown that calmodulin/calcineurin, Ras/cAMP, mTOR and general MAPK signalling pathways help regulate cellular responses in fungi. Project studies showed that the polyketide synthase (pksP) gene cluster is regulated by cAMP and MAPK signalling pathways present in A. fumigatus. This could prove to be a useful biomarker to study crosstalk interaction in MAPK signalling pathways. Researchers also investigated the mechanism of action of Caspofungin (CAS), a cell wall-acting compound and tested its effectiveness through transcriptome analysis. CAS worked by affecting cellular and carbohydrate metabolism. In addition to cell wall stress, CAS affected cell membranes by inducing osmolarity stress. As such, CAS was deemed to be appropriate for use in combination therapy. Also, the peptide MDN-0010 was found to be 4.5 times stronger than CAS against these fungi. To identify key protein phosphatases, a comparative blastp and tblastn analysis was performed and 33 putative protein phosphatases were identified. Phosphatase screening revealed that serine and threonine protein phosphatases are important for cell wall maintenance. Researchers successfully deleted 28 putative protein phosphatase genes and created five inducible mutant strains using fast cloning methodology and Saccharomyces cerevisiae. Currently, there is no effective treatment against aspergillosis. The need for effective therapy has become increasingly important over the last two decades as this disease incidence has increased. Successful project outcomes could reveal novel drug compounds and provide options for effective therapeutic intervention.