6r60

Publication Abstract from PubMed

beta-Propellers arise through the amplification of a supersecondary structure element called a blade. This process produces toroids of between four and twelve repeats, which are almost always arranged sequentially in a single polypeptide chain. We found that new propellers evolve continuously by amplification from single blades. We therefore investigated whether such nascent propellers can fold as homo-oligomers before they have been fully amplified within a single chain. One- to six-bladed building blocks derived from two seven-bladed WD40 propellers yielded stable homo-oligomers with six to nine blades, depending on the size of the building block. High-resolution structures for tetramers of two blades, trimers of three blades, and dimers of four and five blades, respectively, show structurally diverse propellers and include a novel fold, highlighting the inherent flexibility of the WD40 blade. Our data support the hypothesis that subdomain-sized fragments can provide structural versatility in the evolution of new proteins.

Structural diversity of oligomeric beta-propellers with different numbers of identical blades.,Afanasieva E, Chaudhuri I, Martin J, Hertle E, Ursinus A, Alva V, Hartmann MD, Lupas AN Elife. 2019 Oct 15;8. pii: 49853. doi: 10.7554/eLife.49853. PMID:31613220^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.