This slant is acid over acid indicating metabolism of glucose along with lactose and/or sucrose. In addition, gas production (CO2 and O2) is detected by splitting of the agar. In some cases, so much gas is produced that the agar is pushed to the top of the tube.
Bacteria commonly producing an A/A reaction with or without gas include: Enterobacter aerogenes, E. cloacae, Escherichia coli, Klebsiella oxytoca, and K. pneumoniae.
Reference: MacFaddin, J.F. (2000) Biochemical Tests for Identificaion of Medical Bacteria, 3rd. ed. Lippincott Williams & Wilkins, Philadelphia. |
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