The primary structure of Bacillus subtilis acidic ribonsomal protein B-19. Isolation and characterization of peptides and the complete amino acid sequence.

The complete primary structure of Bacillus subtilis acidic protein B-L9, functionally equivalent to protein L7/L12 from E. coli, has been determined. B-L9 is composed of 122 residues and has the amino acid composition: Asp3, ASN3, Thr4, Ser3, Glu22, Gln1, Pro3, Gly11, Ala21, Val14, Ile9, Leu12, Phe2, Lys13, and Arg1. The molecular weight of B-L9 is 12,633. The amino acid sequence was determined by a combination of automated Edman degradation of the intact protein in a modified Beckman sequenator, and micro dansyl-Edman degradation of the peptides obtained from digestions with trypsin, thermolysin, Staphylococcus aureus protease, chymotrypsin and pepsin. A comparison of protein B-L9 from B. subtilis with E-L12 from E. coli shows a relatively high degree of homology.