HSS 1101 Lecture Notes - Antibody, Immunofluorescence, Freeze-Drying
Document Summary
Must be done in order to classify, identify and characterize microorganisms. 3 methods of preservation of cultures: liquid n2: -196 degrees, freezer: -70 to -120, lyophilization(freeze dry): dry, then vaccum seal degrees. 1. 7 - 2 methods of identification of microorganism: colonial morphology: Can be done with the naked eye. Look of bacterial colonies; ie edges, elevation, form: 1. 10 - cellular morphology: Simple stain: single dye used; all same color. Used to see size, shape, number, arrangement etc. Differential stain: stain of differing dyes used to observe differences between microbial cells/cell parts examples: acid fast stain, gram stain. Perhaps the most important staining technique of all! Gram- is thin, completely dissolves, turns clear, becomes permeable: recolorize with safranin: turns gram- pink, gram+ stays purple. Endospore: staining of spores malachite green+heat and then safranin. Capsule: sample treated with copper sulfate first to visualize capsule as clear zone around cells. Flagella: use of mordant to thicken flagella prior to staining for better visualization.
