title: Primary, secondary, and tertiary structure of the core of a histone H1-like protein from the sperm of Mytilus.
abstract: We have analyzed the structure of the trypsin-resistant core of the protein PL-II* of the sperm from Mytilus californianus. The peptide has a molecular mass of 8436 Da and its primary sequence is ATGGAKKP STLSMIVAAIQAMKNRKGSSVQAIRKYILANNKG INTSRLGSAMKLAFAKGLKSGVLVRPKTSAGA SGATGSFRVG. This sequence bears an enormous homology and fulfills the constraints of the consensus sequence of the trypsin-resistant peptides of the proteins of the histone H1 family. Secondary structure analysis using Fourier-transform infared spectroscopy as well as predictive methods indicate the presence of 20-30% beta-structure and approximately 25% alpha-helix for this peptide. As in the case of histone H1 proteins, the protein PL-II* core exhibits a compact globular structure as deduced from hydrodynamic measurements. The presence of a histone H1 protein with protamine-like features, seems to be thus, a common general feature of the chromatin composition in the sperm of the bivalve molluscs.
authors.affiliation: Unidad de Química Macromolecular, Escola Técnica Superior d'Enginyers Industrials de Barcelona Diagonal 647, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Jutglar
authors.forename: J I
authors.initials: JI
authors.lastname: Borrell
authors.forename: J
authors.initials: J
authors.lastname: Ausió
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D049872:Bivalvia; D002852:Chromatography, Ion Exchange; D004268:DNA-Binding Proteins; D005583:Fourier Analysis; D006657:Histones / Q000032:analysis / Q000737:chemistry*; D008297:Male; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000032:analysis / Q000737:chemistry*; D011487:Protein Conformation; D012689:Sequence Homology, Nucleic Acid; D013057:Spectrum Analysis; D013094:Spermatozoa / Q000737:chemistry*; D014357:Trypsin / Q000378:metabolism; D014461:Ultracentrifugation
chemical_list: D004268:DNA-Binding Proteins; D006657:Histones; D009687:Nuclear Proteins; C068699:PL-II protein, Mytilus; D014357:Trypsin