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Symbiosis refers to the partnership (usually long-term) that is established between two or more organisms. In microbiology, symbiotic relationships are often established between a microorganism and its host, and the partnership can be mutualistic or parasitic.
Two new studies provide insights into the close association between Wolbachia spp. and their hosts; one shows plant-mediated transmission and the other the bacterial origin of a new host sex chromosome.