title: Structural properties of the methionine-containing subfraction of rat liver histone H1.
abstract: Cyanogen bromide (CNBr) cleavage of total rat liver histone H1 generates a C-terminal peptide which originates from a methionine-containing subfraction. This subfraction comprises approx. 20% of the whole rat liver H1 population, resembles calf thymus CTL-1 in size but contains methionine and histidine, higher proportions of serine and less alanine and proline. Edman degradation established the N-terminal sequence of the CNBr peptide as Arg-Arg-Lys-Ala-Ser-Gly-Pro-Pro-Val-Glu. By alignment with calf thymus CTL-1, methionine was identified as residue 30 replacing alanine in a non-conservative replacement. Residue 40 is deleted but sequence homology near the double proline sequence in the G-domain is retained. The CNBr peptide is estimated at 177-181 residues and comprises the complete G- and C-domain and two arginines from the basic cluster in the N-domain. Removal from H1 of all but two residues of the N-domain does not abolish secondary and tertiary folding. This GC-peptide opens new approaches to the study of the function of H1 in chromatin.
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002458:Cell Fractionation; D002467:Cell Nucleus / Q000032:analysis; D002918:Chymotrypsin; D003488:Cyanogen Bromide; D004591:Electrophoresis, Polyacrylamide Gel; D006657:Histones / Q000302:isolation & purification*; D008099:Liver / Q000032:analysis*; D008715:Methionine; D008970:Molecular Weight; D010446:Peptide Fragments / Q000032:analysis; D051381:Rats
chemical_list: D000596:Amino Acids; D006657:Histones; D010446:Peptide Fragments; D008715:Methionine; D002918:Chymotrypsin; D003488:Cyanogen Bromide