The primary structure of amyloid fibril protein AA in endotoxin-induced amyloidosis of the mink.

Two AA proteins were isolated from the same amyloid fibril preparation from the liver of a mink, in which amyloidosis had been induced by injections with endotoxin. The two proteins were of different size, one containing 53 amino acid residues and the other 64 residues. The amino acid sequence was otherwise found to be identical. Both proteins revealed pyrrolidone carboxylic acid as the N-terminal amino acid. Sequence homologies with protein AA from other species were very striking. However, no antigenic cross-reaction was seen between mink protein AA and antisera to protein AA from human, mouse or rabbit sources.