The Complete Amino‐Acid Sequence of Histone H2B1 from Sperm of the Sea Urchin Parechinus angulosus

Two histones have been isolated and purified from sperm cells of the sea urchin Parechinus angulosus. They have been designated sperm histone H2B(1) Parechinus and sperm histone H2B(2) Parechinus on criteria of solubility and partial sequence homology with H2Bcalf. H2B1 consists of a polypeptide chain of the following 144 amino acid residues: Pro‐Ser‐Gln‐Lys‐Ser‐Pro‐Thr‐Lys‐Arg‐Ser‐Pro‐Thr‐Lys‐Arg‐Ser‐Pro‐Thr‐Lys‐Arg‐Ser‐Pro‐Gln‐Lys‐Gly‐Gly‐Lys‐Gly‐Gly‐Lys‐Gly‐Ala‐Lys‐Arg‐Gly‐Gly‐Lys‐Ala‐Gly‐Lys‐Arg‐Arg‐Arg‐Gly‐Val‐Gln‐Val‐Lys‐Arg‐Arg‐Arg‐Arg‐Arg‐Arg‐Glu‐Ser‐Tyr‐Gly‐Ile‐Tyr‐Ile‐Tyr‐Lys‐Val‐Leu‐Lys‐Gln‐Val‐His‐Pro‐Asp‐Thr‐Gly‐Ile‐Ser‐Ser‐Arg‐Ala‐Met‐Ser‐Val‐Met‐Asn‐Ser‐Phe‐Val‐Asn‐Asp‐Val‐Phe‐Glu‐Arg‐Ile‐Ala‐Ala‐Glu‐Ala‐Gly‐Arg‐Leu‐Thr‐Thr‐Tyr‐Asn‐Arg‐Arg‐Ser‐Thr‐Val‐Ser‐Ser‐Arg‐Glu‐Val‐Gln‐Thr‐Ala‐Val‐Arg‐Leu‐Leu‐Leu‐Pro‐Gly‐Glu‐Leu‐Ala‐Lys‐His‐Ala‐Val‐Ser‐Glu‐Gly‐Thr‐Lys‐Ala‐Val‐Thr‐Lys‐Tyr‐Thr‐Thr‐Ser‐Arg. In a previously published partial sequence serine was incorrectly assigned to position 30. A comparison of the carboxyl‐terminal two thirds of H2B(1) Parechinus and H2Bcalf reveals that 79% of the corresponding positions are occupied by identical amino acid residues. Much of the variability occurs in a short polar region of 20 amino acid residues. The remainder of C‐terminal regions is hydrophobic and almost completely invariable. A comparison of the amino‐terminal one third of H2B(1) Parechinus and H2Bcalf reveals that they are both highly basic with a considerable homology of the position of basic amino acids. Further, H2B(1) Parechinus possesses an amino terminal extension of 19 amino acids. These 19 amino acids can be recognized as a repeating pentapeptide. Copyright © 1977, Wiley Blackwell. All rights reserved