12th December, 2014
MCB 3020L- Section 018
Unknown #16
Abstract
This report contains the background information on gram positive and gram negative bacteria, which will aid in understanding the use of specific laboratory experiments to distinguish between the two types of bacteria. Included are the materials and methods used to identify the gram positive and gram negative bacteria and methods which also differentiate between microbes of each group. The implications of the methods of identification used are also described in this report to give an explanation as to why a certain route was taken in carrying out experiment 14. The results of the experiment carried out for the identification of three unknowns are tabulated and then these are discussed to give an explanation as to why such results were gotten and what the results show to prove the identity of a certain bacteria. The bacteria identified in unknown #16 are: Klebsiella pneumonia, Staphylococcus epidermidis and Yersinia enterocolitica.
Introduction
Microorganisms, which are organisms that can be seen only with the use of a microscope, are both important and hazardous to human life. In the medical field, it is of utmost importance to be able to identify these organisms because they help to determine the cause of an illness and the consequent treatment needed (Slonczewski, 2013). The purpose of experiment #14 is to identify each bacteria in an unknown mixture, using a number of laboratory tests. Over the semester, multiple tests were carried out to identify between gram-positive and gram-negative bacteria including the Mannitol Salt Agar (MSA) media test, which selects only for gram positive bacteria, and the use of Eosin Methylene Blue Levine (EMB) Agar media, which selects for gram negative bacteria and differentiates between lactose fermenters (paracolons) and non-lactose fermenters (coliforms).These tests along with other selective and/or differential media, and
Cited: Arvidson, C. (n.d.). Cultivation Media for Bacteria. Retrieved December 3, 2014, from http://learn.chm.msu.edu/vibl/content/differential/ Carson, V. (2013). Microbiology Lab (1st ed.). Department of Cell Biology, Microbiology & Molecular Biology. University of South Florida. Slonczewski, J., & Foster, J. (2013). Microbiology: An evolving science (Third ed.). W. W. Norton. U.S Food and Drug Administration. (2014, October 7). BBB - Yersinia enterocolitica. Retrieved November 28, 2014, from http://www.fda.gov/Food/FoodborneIllnessContaminants/CausesOfIllnessBadBugBook/ucm070040.htm