Is there such a thing as an obligatorily multicellular prokaryote? Merry Youle of the Small Things Considered blog reviews a recent paper published in the May issue of Applied and Environmental Microbiology that announces the finding of a new subgroup within magnetotactic multicellular prokaryotes.
"These new critters have a similar life cycle and morphology. They, too, are sulfate-reducers, but they are found in low-saline, nonmarine aquatic environments, and they are not magnetotactic—thus called non-Magnetotactic Multicellular Prokaryotes or nMMPs. Although they don't navigate by compass, they do exhibit active negative phototaxis—the first δ-proteobacteria known to do so."
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