Chemotaxis and localization of the archaellum in Haloferax volcanii

Although archaea use a totally different motility machinery than bacteria, eg. euryarchaea have obtained the full chemotaxis system from bacteria via horizontal gene transfer.

However, the archaellum has no FliM, to which CheY binds in bacteria. Therefore archaea have adaptor proteins, like CheF, which interact with CheY and the archaellum motor.

Interestingly, the CheY structure between the archaeal and the bacterial one is very similar except for the FliM binding site.

Morever, we found that the archaella of H. volcanii are positioned at the poles. H. volcanii is mainly motile during the very early log phase when the cells are rod-shaped. When the cells round up during growth, the filament is disassembled and only the archaellar motor is still present.

Papers:

Li Z, Kinosita Y, Rodriguez-Franco M, Nußbaum P, Braun F, Delpech F, Quax TEF, Albers SV. (2019) Positioning of the Motility Machinery in Halophilic Archaea.

mBio. 10(3). pii: e00377-19. doi: 10.1128/mBio.00377-19.

Quax TEF, Altegoer F, Rossi F, Li Z, Rodriguez-Franco M, Kraus F, Bange G, Albers SV. (2018) Structure and function of the archaeal response regulator CheY.

Proc Natl Acad Sci U S A. 115(6):E1259-E1268. doi: 10.1073/pnas.1716661115.