FIG. 11.

(A) Homology between human cardiac myosin residues 1313 to 1329 and streptococcal M5 protein peptide B2 (M5 residues 150 to 167). Identity (47%) was observed in a 17-amino-acid overlap. The M5 peptides B2, B1B2, and B3A contain large amounts of overlapping sequence. :, identical residues; ., conserved substitutions. Three of the residues shown in panel A in the myosin sequence are unique to human cardiac myosin. (B) Amino acid sequence identity (LKTEN) between M5 peptide NT4 and human cardiac myosin (LQTEN). NT4 contains residues 40 to 58 of the M5 protein. The cardiac myosin sequence shown is found in residues 1279 to 1286 near the beginning of the light meromyosin tail and the end of the S-2 fragment of myosin. The myosin sequence shown in panel B is conserved among cardiac myosins. (C) Amino acid sequence identity between serotype M6 protein and human cardiac myosin within the same regions. The repeat in the M6 protein is LTTEN, which is repeated five times in the N-terminal region of the M6 protein. In M5 and M6 proteins, the LKTEN and LTTEN sequences, respectively, are conserved and are similar to the LQTEN sequence in cardiac myosins. (Reprinted from reference 123 with permission from the publisher.)