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A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
Published on: February 19, 2019
Evolutionary origin of the Rhodobacter sphaeroides specialized RpoN sigma factors
Clelia Domenzain1, Laura Camarena, Aurora Osorio
1Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México City, México.
Abstract:
Gene duplication and horizontal gene transfer (HGT) are two events that enable the generation of new genes. Rhodobacter sphaeroides (WS8 and 2.4.1 strains) has four copies of the rpoN gene that are not functionally interchangeable. Until now, this is the only example of specialization of this sigma factor. In this work, we aimed to determine whether the multiple copies of this gene originated from HGT or through gene duplication. Our results suggest a multiplication origin of the different rpoN copies that occurred after the Rhodobacter clade separated. Functional tests indicate that the specialization of the rpoN genes is not restricted to R. sphaeroides. We propose that the rpoN copy involved in nitrogen fixation is the ancestral gene and that the other rpoN genes have acquired new specificities.
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