• PhD, Stanford University
• Postdoctoral Research, University of Wisconsin

The Free Laboratory is interested in the Molecular, Cellular, and Developmental Biology of the filamentous fungi. The major focus of our research has been on characterizing cell wall biosynthesis in N. crassa. We have identified the major glycoproteins and polysaccharides present in the cell wall. We are in the process of characterizing how the glycoproteins and polysaccharides become incorporated into the cell wall. We are characterizing the enzymatic properties of the various glycoproteins present in the cell wall function. We are examining how the cell wall changes throughout the fungal life cycle.  We are also currently engaged in a research project to characterize how female development is regulated in Neurospora crassa. We have identified transcription factors and signal transduction pathways that function to control female development.

• Chatrath, A., Patel, P., Dey, P., and Free, S.J. Characterization of the Neurospora crassa GH72 family of Laminarin/Lichenin transferases and their roles in cell wall biogenesis. The Cell Surface 13 (2025) 100140 https.//doi.org/10.1016/j.tcsw.2024.100140
• Chatrath, A., Dey, P., Greeley, K., Maciel, G., Huang, L., Heiss, C., Black, I., Azadi, P., and Free, S.J. Characterization of the Neurospora crassa galactosaminogalactan biosynthetic pathway. Microorganisms 12 1509 (2024) https://doi.org/10.3390/microorganisms12081509
• Schaff, H., Dey, P., Heiss, C., Keiser, G., Moro, T.R., Azadi, P., Patel, P., and Free, S.J. Characterization of the need for galactofuranose during the Neurospora crassa life cycle. Fungal Genet. Biol. 168 (2023) 103826 https://doi.org/10.1016/j.fgb.2023.103826
• Shoma, J.F., Ernan, B., Keiser, G., Heiss, C. Azadi, P., and Free, S.J. Genetic Characterization of the Acidic and Neutral Glycosphingolipid biosynthetic pathways in Neurospora crassa. Microorganisms 2023, 11, 2093. https://doi.org/10.3390/microorganisms11082093
• Patel, P.K., Kar, B., and Free (2022) Characterization of the Neurospora crassa GH72 cell wall cross-linking glucanosyltransferases.  The Cell Surface 8 (2022) 100073 https://doi.org/10.1016/j.tcsw.2022.100073
• Patel, P.K., Tung. S.K., Porfirio, S., Sonon, R., Azadi, P., and Free, S.J. (2022) Extracellular targeting of Neurospora crassa cell wall and secreted glycoproteins by DFG-5.  Fungal Genet. Biol. 160 (2022) 103686  https://doi.org/10.1016/j.fgb.2022.103686
• Patel, P.K. and Free, S.J. (2022) Characterization of Neurospora crassa GH16, GH17, and GH72 gene families of cell wall crosslinking enzymes.  The Cell Surface 8:100073.  https://doi.org/10.1016/j.tcsw.2022.100073
• Patel, P. and Free, S. (2020) Characterizing the role of an α-1,6-mannanase needed for Neurospora crassa cell wall biogenesis.  FASEB J. 34(S1):1 https://doi.org/10.1096/fasebj.2020.34.s1.09202
• Patel, P.K. and Free, S.J. (2019) The genetics and biochemistry of cell wall structure and synthesis in Neurospora crassa, a model filamentous fungus.  Frontier in Microbiology 10:2294. https://doi:10.389/fmicb.2019.02294
• Kar, B., Patel, P.K., and Free, S.J.  (2019) Trichophyton rubrum LysM proteins bind to fungal cell wall chitin and to the N-linked oligosaccharides present on human skin glycoproteins. PLOS ONE 14:e0215034.  https://doi.org/10.1371/journal.pone.0215034
• Kar., B., Patel, P., Ao, J., and Free, S.J. (2019) Neurospora crassa family GH72 glucanosyltransferases function to crosslink cell wall glycoprotein N-linked oligosaccharides to cell wall lichenin.  Fungal Genet. Biol. 123:60-69.o  https://doi.org/10.1016.j.fgb.2018.11.007
• Ao, J., Bandyopadhyay, S., and Free, S.J. (2018) Characterization of the Neurospora crassa DHN melanin biosynthetic pathway in developing ascospores and peridium cells. Fungal Biology https://doi.org/10.1016/j.funbio.2018.10.005
• Chow, J., Notaro, M., Prabhakar, A., Free, S.J., and Cullen, P.J. (2018) Impact of fungal MAPK pathway targets on the cell wall.  J. Fungi 4:93-109.  https://doi:10.3390/jof4030093
• Ao, J. and Free, S.J. (2017) Genetic and biochemical characterization of the GH72 family of cell wall transglycosylases in Neurospora crassa.  Fungal Genet. Biol. 101:46-54.  http://dx.doi.org/10.1016/j.fgb.2017.03.002
• Ao, J., Aldabbous, M., Notaro, M.J., Lojacono, M. and Free, S.J. (2016) A proteomic and genetic analysis of the Neurospora crassa conidia cell wall proteins identifies two glycosyl hydrolases involved in cell wall remodeling.  Fungal Genet. Biol. 94:47-53.  http://dx.doi.org/10.1016/j.fgb.2016.07.003