(Figure Presented) GroELSP/MC, prepared by genetic and chemical modifications of group I chaperonin protein GroEL, site-specifically possesses ∼28 photochromic (spiropyran [SP] and merocyanine [MC]) units in the entrance parts of its cavity. Addition of divalent metal ions such as Mg 2+ to a tris-HCl buffer solution of GroELSP/MC results in one-dimensional (1D) assembly of GroELSP/MC, affording cylindrical hollow fibers with a very large aspect ratio; the longest fiber was ∼2.5 μm long, corresponding to a 170-mer of GroELSP/MC (MW ≈ 1.4 × 108). When such long fibers are mixed with EDTA, they are cut into short-chain oligomers and eventually into monomeric GroELSP/MC. Similar to GroEL, GroELSP/MC possesses a large binding affinity toward denatured proteins. When GroELSP/MC undergoes 1D assembly after incubation with a denatured protein, guest-containing cylindrical fibers result.
ASJC Scopus subject areas
- Colloid and Surface Chemistry