Primary structure of chicken cardiac myosin S-1 heavy chain.
The sequence of the NH2-terminal 830 amino acid residues of chicken cardiac ventricular muscle myosin subfragment-1 (S-1) was determined. S-1 was obtained by limited chymotryptic digestion, and cleaved into three characteristics fragments (23, 41, and 22 kDa fragments) by limited tryptic digestion. These fragments were isolated by gel filtration on a Sephadex G-100 column, followed by cation-exchange chromatography on a CM-52 column and reverse-phase HPLC. The isolated fragments were sequenced completely. Peptides overlapping the 23 and 41 kDa fragments and also overlapping the 41 and 22 kDa fragments were obtained by cleaving S-1 with cyanogen bromide, and sequenced completely. We also obtained a minor fragment, the 20 kDa fragment, in addition to the three characteristic fragments. Amino acid compositions of the cyanogen bromide peptides of the 20 kDa fragment indicated that a portion of S-1 heavy chains had lost their COOH-terminal 21 residues during limited tryptic digestion. Methylated amino acid residues were found at four positions: epsilon-N-monomethyllysine at position 32, epsilon-N-trimethyllysine residues at 127 and 549, and 3-N-methylhistidine at 754.
Department of Biochemistry, Nagasaki University School of Medicine.
S
S
Nakayama
H
H
Tanaka
E
E
Yajima
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T
Maita
D000595:Amino Acid Sequence; D000818:Animals; D002645:Chickens; D002918:Chymotrypsin; D006352:Heart Ventricles / Q000737:chemistry*; D008969:Molecular Sequence Data; D009218:Myosins / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid
D002918:Chymotrypsin; D009218:Myosins