Harnessing calcineurin-FK506-FKBP12 crystal structures from invasive fungal pathogens to develop antifungal agents
Journal
Nature Communications
Journal Volume
10
Journal Issue
1
Date Issued
2019
Author(s)
Juvvadi, P.R.
Fox, D.
Bobay, B.G.
Hoy, M.J.
Gobeil, S.M.C.
Venters, R.A.
Chang, Z.
Lin, J.J.
Averette, A.F.
Cole, D.C.
Barrington, B.C.
Wheaton, J.D.
Ciofani, M.
Trzoss, M.
Li, X.
Lee, S.C.
Mutz, M.
Spicer, L.D.
Schumacher, M.A.
Heitman, J.
Steinbach, W.J.
Abstract
Calcineurin is important for fungal virulence and a potential antifungal target, but compounds targeting calcineurin, such as FK506, are immunosuppressive. Here we report the crystal structures of calcineurin catalytic (CnA) and regulatory (CnB) subunits complexed with FK506 and the FK506-binding protein (FKBP12) from human fungal pathogens (Aspergillus fumigatus, Candida albicans, Cryptococcus neoformans and Coccidioides immitis). Fungal calcineurin complexes are similar to the mammalian complex, but comparison of fungal and human FKBP12 (hFKBP12) reveals conformational differences in the 40s and 80s loops. NMR analysis, molecular dynamic simulations, and mutations of the A. fumigatus CnA/CnB-FK506-FKBP12-complex identify a Phe88 residue, not conserved in hFKBP12, as critical for binding and inhibition of fungal calcineurin. These differences enable us to develop a less immunosuppressive FK506 analog, APX879, with an acetohydrazine substitution of the C22-carbonyl of FK506. APX879 exhibits reduced immunosuppressive activity and retains broad-spectrum antifungal activity and efficacy in a murine model of invasive fungal infection. ? 2019, The Author(s).
SDGs
Other Subjects
antifungal agent; APX879; calcineurin; cyclophosphamide; fk 506 binding protein; fluconazole; tacrolimus; triamcinolone; unclassified drug; antifungal agent; calcineurin; calcineurin inhibitor; fk 506 binding protein; tacrolimus; crystal structure; disease treatment; fungal disease; fungus; inhibition; molecular analysis; mutation; protein; virulence; animal cell; animal experiment; animal model; animal tissue; antifungal activity; antifungal susceptibility; Article; aspergillosis; Aspergillus fumigatus; Candida albicans; cell culture; CFU counting; Coccidioides immitis; controlled study; Cryptococcus neoformans; crystal structure; DNA sequence; drug efficacy; drug synthesis; female; flow cytometry; fluorescence microscopy; fungus; gene mutation; genetic transfection; immunosuppressive treatment; infectious agent; invasive candidiasis; male; minimum inhibitory concentration; molecular docking; molecular dynamics; molecular model; mouse; mucormycosis; nonhuman; nuclear magnetic resonance; polymerase chain reaction; protein conformation; protein expression; protein isolation; protein purification; single drug dose; site directed mutagenesis; size exclusion chromatography; Western blotting; X ray crystallography; A J mouse; animal; aspergillosis; binding site; C57BL mouse; Coccidioides; cryptococcosis; drug development; drug effect; metabolism; microbiology; procedures; Aspergillus fumigatus; Candida albicans; Coccidioides immitis; Filobasidiella neoformans; Mammalia; Murinae; Animals; Antifungal Agents; Aspergillosis; Aspergillus fumigatus; Binding Sites; Calcineurin; Calcineurin Inhibitors; Candida albicans; Cells, Cultured; Coccidioides; Cryptococcosis; Cryptococcus neoformans; Crystallography, X-Ray; Drug Discovery; Female; Male; Mice; Mice, Inbred A; Mice, Inbred C57BL; Molecular Dynamics Simulation; Tacrolimus; Tacrolimus Binding Protein 1A
Type
journal article