A microbiologist is trying to isolate a pathogen expected to be present in very small numbers from a stool specimen in which there are abundant normal microbiota.Which strategy would most likely accomplish this purpose?

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Enrichment culture followed by culture on selective agar would provide the best chance for isolating the pathogen by allowing it to grow in a specific and enriched environment. This would increase the amount of the pathogen relative to other organisms in the sample, making it more likely that it would be successfully isolated on selective agar. Culture on enriched media alone would likely provide a favorable growth environment for both the pathogen and normal microbiota, resulting in a mixed culture that would be difficult to identify. Culture on differential media would allow for the differentiation of different organisms based on their characteristics, but would not necessarily favor one organism over another. Culture in an anaerobe jar would only be beneficial if the pathogen was an anaerobe, which cannot grow in the presence of oxygen, and would not necessarily isolate it from normal microbiota.

A Microbiologist Is Trying to Isolate a Pathogen Expected to Be