Phenotypic characterization of Histoplasma species

Evaluation of extracellular proteolytic activity: To evaluate extracellular proteolytic activity in different species of Histoplasma, we grew the 27 Histoplasma strains (Table S1) in HMM plates supplemented with 1.5% skim milk. Strains with a proteolytic activity show a clear halo around their yeast colonies.Optical density and growth curves of Histoplasma yeast cultures: We mixed 600 μl of liquid culture with 300 μl of 3M NaOH in a plastic cuvette, which was covered with Parafilm and vortexed for 10 seconds to separate yeast clumps and measure optical density (OD) in a GENESYS 10vis spectrophotometer (Thermo Spectronic) starting at day 0, and at every 24 hours after that until day 11.Yeast Area: We mixed 10 μl from a yeast culture that had large yeast clumps removed with 10 μl of Lactophenol Cotton Blue on a glass slide. Differential interference contrast (DIC) images were obtained using 100X/1.4 Oil UPlan S Apo PSF quality objective on an Olympus BX-61 microscope and collected using a QImaging RETIGA 4000R color camera and Volocity 6.3 acquisition software.Description of the data and file structureWe are including four files: Three of them are experimental observations, and one of them is the code required to analyze the data.halo_radius_miss.csv: ratio sizes of H. mississipiense cultures in .5% skim milk media. The variable halo is in cms and reflects the ratio of the lysis halo. Isolate refers to the name of the Histoplasma strain.od_cells_histo.csv: rates of growth of different species of Histoplasma in liquid media. Strain refers to the name of the Histoplasma strain. OD refers to the turbidity of the culture (reported in Absorbance Units). Cells is the number of cells in the culture.Cell_Size_df.csv: cell size for different species of Histoplasma. Line refers to the name of the Histoplasma strain. Replicate refers to the number of the experimental batch. Area is the ellipse area of the cell (in micrometers^2).histoplasma_morphology_code.R: Analytical code to generate linear models.