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Unknowns. 1st lab session. Two unknown slants One is gram+ and the other is gram -. Unknowns will be numbered Inoculate each unknown on to a Brain Heart Infusion Agar (BHIA) – subculture (working culture) 2. Inoculate each unknown on MacConkey Agar – do streaking for isolation
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1st lab session Two unknown slants One is gram+ and the other is gram -. Unknowns will be numbered • Inoculate each unknown on to a Brain Heart Infusion Agar (BHIA) – subculture (working culture) 2. Inoculate each unknown on MacConkey Agar – do streaking for isolation Gram staining on each unknown Label the plates, slides, tubes with the appropriate unknown numbers. Incubate all at 37oC
2nd lab session • Examine MacConkey for growth • No growth – gram positive • Growth – gram negative • These results will confirm the gram staining results • Do catalase test only on gram positive unknown • Catalase + Staphylococcus, catalase – Streptococcus
Gram negative unknown • Examine the isolated colonies on MacConkey and determine the color of the colony. • Pink – lactose fermenter • White/colorless – lactose nonfermenter • We do not need this information for gram positive.
Non- fermenter • TSI slant – only one • Urea broth • Fermenter • Tryptone broth – 1 • MRVP – 2 • Citrate slant – 1 • Urea broth – 1 • Motility - 1
3rd lab session • Match the results on your unknown with the results on the tables for the known bacteria.
Table 3 Table 1 Table 2 Table 4