Alphaproteobacteria
class of bacteria
Alphaproteobacteria or α-proteobacteria, also called α-Purple bacteria in earlier literature, is a class of bacteria in the phylum Pseudomonadota (also called "Proteobacteria"). The Magnetococcales and Mariprofundales are considered basal or sister to the Alphaproteobacteria. The Alphaproteobacteria are highly diverse and possess few commonalities, but share a common ancestor. Like all proteobacteria, its members are gram-negative, although some of its intracellular parasitic members lack peptidoglycan and are consequently gram variable.
Characteristics
The Alphaproteobacteria include several phototrophic genera, some metabolising C1-compounds (e.g. Methylobacterium spp.), symbionts of plants (e.g. Rhizobium spp.), endosymbionts of arthropods (Wolbachia) and intracellular pathogens (e.g. Rickettsia). Moreover, the class is sister to the protomitochondrion, the bacterium that was engulfed by the eukaryotic ancestor and became the mitochondria (see Endosymbiotic theory). A species of technological interest is Agrobacterium tumefaciens (also called Rhizobium radiobacter): scientists often use this species to transfer foreign DNA into plant genomes.
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This entry incorporates text from “Alphaproteobacteria” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.