Unformatted text preview: 12-6-10
Lab: LR11 Gram Negative Biochemical Testing
Objective: Examine the metabolism of microorganisms
Phenyl alanine E. aerogenosa
A/A E. coli
- P. mirabilis
K/K [sulfur (H2S) no
+ Conclusion/Discussion: E. coli was positive for methyl red, TSI, and indole. E. aerogenosa was positive for
Voge’s Prauskauer, citrate, and motility. P. mirabilis metabolized glucose but there was no fermentation,
and it was positive for methyl red, citrate, nitrate, urease, sulfur reduction, indole, motility and phenyl alanine.
E. aerogenosa metabolized and fermented both sucrose and glucose, while E. coli was able to metabolize
and create fermentation with both glucose and lactose. E. aerogenosa was able to metabolize lactose but no
fermentation was evident. The test results were consistent with the outcomes expected. These tests showed
the various ways in which you can differentiate between different gut bacteria within Enterobacteriaceae,
which is valuable in identifying an unknown organism. ...
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