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To analyze:
The tests that is necessary further to identify red colony producing bacteria on MacConkey agar.
Introduction:
MacConkey agar stands as a differential media of lactose and non-lactose fermenters by producing red colonies for the former and colourless colonies for the latter respectively. Further certain tests can be undergone to identify the organism.
Explanation of Solution
The gram negative rods that is oxidase-negative and that which ferments lactose can be subjected to check for the presence of Hydrogen sulphide production. If Hydrogen sulphide test is positive the bacterium can be a Citrobacter. If it is negative to Hydrogen sulphide test then Indole test can be performed. If it is positive to Indole test it is Escherichia and if it is negative mobility test can be done. If there is mobility then it can be Enterobacter and if there is no mobility then it is Klebsiella.
Thus the above tests can be performed to confirm the identity of the bacterium.
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Chapter 48 Solutions
Laboratory Experiments in Microbiology (11th Edition)
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