Petri dish culture of the bacterium Rhizobium leguminosarum, a nitrogen fixing bacteria, growing on YMA medium (yeast manitol medium). The picture sho

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Petri dish culture of the bacterium Rhizobium leguminosarum, a nitrogen fixing bacteria, growing on YMA medium (yeast manitol medium). The picture shows the pattern of streaking used to isolate single colonies. Parallel lines are drawn across the culture using a platinum wire loop as seen here. These lines are crossed and recrossed at different angles, diluting the culture until colonies originally formed around a single bacterium are isolated. The small blobs in the foreground are single colonies. Streaking is an essential technique for isolating particular strains or mutant bacteria in mixed cultures.

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Size: 4214px × 4240px
Photo credit: © DR JEREMY BURGESS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: bacterial, culture, dish, equipment, healthcare, lab, laboratory, legumino, leguminosarum, loop, medical, medicine, micro-organism, microbiological, microbiology, petri, research, rhizobium, streaking, technique, wire