Archaeal DNA-import apparatus is homologous to bacterial conjugation machinery

Archive ouverte

Beltran, Leticia, C | Cvirkaite-Krupovic, Virginija | Miller, Jessalyn | Wang, Fengbin | Kreutzberger, Mark, a B | Patkowski, Jonasz, B | Costa, Tiago, R D | Schouten, Stefan | Levental, Ilya | Conticello, Vincent, P | Egelman, Edward, H | Krupovic, Mart

Edité par CCSD ; Nature Publishing Group -

International audience. Conjugation is a major mechanism of horizontal gene transfer promoting the spread of antibiotic resistance among human pathogens. It involves establishing a junction between a donor and a recipient cell via an extracellular appendage known as the mating pilus. In bacteria, the conjugation machinery is encoded by plasmids or transposons and typically mediates the transfer of cognate mobile genetic elements. Much less is known about conjugation in archaea. Here, we determine atomic structures by cryo-electron microscopy of three conjugative pili, two from hyperthermophilic archaea (Aeropyrum pernix and Pyrobaculum calidifontis) and one encoded by the Ti plasmid of the bacterium Agrobacterium tumefaciens, and show that the archaeal pili are homologous to bacterial mating pili. However, the archaeal conjugation machinery, known as Ced, has been ‘domesticated’, that is, the genes for the conjugation machinery are encoded on the chromosome rather than on mobile genetic elements, and mediates the transfer of cellular DNA.

Suggestions

Du même auteur

The structures of two archaeal type IV pili illuminate evolutionary relationships

Archive ouverte | Wang, Fengbin | CCSD

International audience. We have determined the cryo-electron microscopic (cryo-EM) structures of two archaeal type IV pili (T4P), from Pyrobaculum arsenaticum and Saccharolobus solfataricus, at 3.8 Å and 3.4 Å resol...

Structures of filamentous viruses infecting hyperthermophilic archaea explain DNA stabilization in extreme environments

Archive ouverte | Wang, Fengbin | CCSD

International audience. Living organisms expend metabolic energy to repair and maintain their genomes, while viruses protect their genetic material by completely passive means. We have used cryo-electron microscopy ...

Two distinct archaeal type IV pili structures formed by proteins with identical sequence

Archive ouverte | Liu, Junfeng | CCSD

International audience. Type IV pili (T4P) represent one of the most common varieties of surface appendages in archaea. These filaments, assembled from small pilin proteins, can be many microns long and serve divers...

Chargement des enrichissements...