Histone H1 structure probed by Staphylococcus aureus V8-proteinase.
Proteolytic digestion of calf thymus histone H1 with Staphylococcus aureus V8-proteinase under structuring conditions generates one major limit peptide P1 which consists of approx. 170 residues. Edman degradation establishes the N-terminal sequence as: Leu-Ile-Thr-Lys-Ala-Val-Ala-Ala-Ser-Lys. Chymotryptic fingerprinting shows that the C-terminal part of the H1 molecule is fully preserved. The peptide therefore comprises the residues H1 (42-210). The Glu-41 cleavage is extremely unusual as it occurs in the structured G-domain which is known to be resistant to proteinases (Hartman, P. G., Chapman, G. E., Moss, T. and Bradbury, E. M. (1977) Eur. J. Biochem. 77, 45-71; Böhm, L., Sautière, P., Cary, P. D. and Crane-Robinson, C. (1982) Biochem. J. 203, 577-582). The V8-proteinase cleavage product H1 (42-210) shows only 20% folding as compared to 95-99% folding shown by the peptides H1 (34-121), H1 (31-210) and H1 (33-210). Folding of the G-domain thus critically depends upon the presence of the eight residues 33-41 amongst which the Gly-Pro-Pro sequence at position 36-38 and a beta-turn predicted at position 35 are considered to be particularly important. The location of the cleavage site in the G-domain renders Staphylococcus aureus V8-proteinase suitable as a structural probe.
Böhm
L
L
Radiobiology Laboratory, Faculty of Medicine, University of Stellenbosch, Tygerberg, R.S.A.
Sautière
P
P
Cary
P D
PD
Meader
D L
DL
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002417:Cattle; D002918:Chymotrypsin; D006657:Histones; D010446:Peptide Fragments; D011487:Protein Conformation; D012697:Serine Endopeptidases; D013211:Staphylococcus aureus / Q000201:enzymology; D013950:Thymus Gland
D000596:Amino Acids; D006657:Histones; D010446:Peptide Fragments; D012697:Serine Endopeptidases; D002918:Chymotrypsin; C028344:glutamyl endopeptidase