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Well, Macconkey Agar II plates have Gram Crystal Violet in them so there are a number of bacterial species that can absorb it and turn "very pink." The way to narrow it down is to identify whether it grows in chains or clusters. But other than that, it is hard to tell.

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14y ago
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12y ago

MacConkeys Agar is a special bacterial growth medium that is selective for Gram negative bacteria and can differentiate those bacteria that are able to ferment lactose. It contains bile salt and crystal violet to inhibit the growth of most Gram positive bacteria.

Lactose fermenting bacteria produce pink color colonies on MacConkeys Agar .

Following bacteria can produce pink colour colonies ...

Escherichia Coli



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Q: What microorganism forms a pink colony on MacConkey agar?
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