Figure 2.

Amyloid-like aggregates of CsgA_ss-NM are seeding-competent and infectious. (A) E. coli cell extracts containing SDS-soluble NM-GFP were seeded with scraped cell samples (*) (CsgA_ss-NM, CsgA_ss-M, or CsgA) or with yeast extracts (**) prepared from a [PSI⁺] or [psi⁻] strain. Seed-only control samples consisted of the CsgA_ss-NM scraped cell sample or the [PSI⁺] yeast extract diluted into E. coli cell extracts containing overproduced GFP only. Cartoon depicts experimental protocol. Samples from seeded reactions were removed at the indicated time points and treated with 2% SDS, and the presence of SDS-stable aggregates was assayed by filter retention. SDS-stable aggregates that were retained were probed with an anti-GFP antibody. (B) Infection of [pin⁻][psi⁻] yeast spheroplasts with NM-GFP aggregates isolated by centrifugation from the seeding reactions at the 30-min time point and either sonicated (post-sonication) or not (presonication). Cartoon depicts experimental protocol.