MICRB265 Study Guide - Quiz Guide: Growth Medium, Escherichia Coli, Enterobacter Aerogenes

• School: University of Alberta
• Department: Microbiology (Biological Sciences)
• Course: MICRB265
• Professor: Brian Lanoil

Document Summary

Lab 3 identification of gram- positive and gram-negative bacteria using a biochemical approach: pure culture is required for the identification of a bacterium. Identification of bacteria requires detailed examination of metabolic and nutritional properties as these are determined by the genetic makeup of the cell: the (cid:373)ai(cid:374) refere(cid:374)(cid:272)e te(cid:454)t for (cid:271)a(cid:272)terial ta(cid:454)o(cid:374)o(cid:373)(cid:455): berge(cid:455)(cid:859)s ma(cid:374)ual of deter(cid:373)i(cid:374)ati(cid:448)e. Bacteriology: meta(cid:271)oli(cid:272) tests gi(cid:448)e a (cid:448)isual result (cid:271)(cid:455) usi(cid:374)g (cid:272)olour i(cid:374)di(cid:272)ators. It is ofte(cid:374) (cid:272)alled (cid:858)readi(cid:374)g a test(cid:859): both positive and negative result have value in bacterial taxonomy. Identification of truly novel bacteria must be accompanied by sequencing 16s rrna genes. Test for both species: catalase test: tests for the enzyme catalase. Catalase protects the cell from h2o2 by catalysing the break down of h2o2 to h2o and o2. Present in all organisms that grow in the presence of oxygen (obligate aerobes and facultative anaerobes) Aerotolerant anaerobes and microaerophilic bacteria are catalase negative.