Amino Acid Sequence Analysis of Fish Myosin

Research Project

Project/Area Number	07456093
Research Category	Grant-in-Aid for Scientific Research (B)
Allocation Type	Single-year Grants
Section	一般
Research Field	Fisheries chemistry
Research Institution	HOKKAIDO UNIVERSITY
Principal Investigator	NISHITA Kiyoyoshi Hokkaido Univ., Fac.of Fish., Pro., 水産学部, 教授 (20001620)
Co-Investigator(Kenkyū-buntansha)	TANAKA Hiroyuki Hokkaido Univ., Fac.of Fish., Instruc., 水産学部, 助手 (90241372) OJIMA Takao Hokkaido Univ., Fac.of Fish., Associate Pro., 水産学部, 助教授 (30160865)
Project Period (FY)	1995 – 1997
Project Status	Completed (Fiscal Year 1997)
Budget Amount *help	¥7,000,000 (Direct Cost: ¥7,000,000) Fiscal Year 1997: ¥900,000 (Direct Cost: ¥900,000) Fiscal Year 1996: ¥2,600,000 (Direct Cost: ¥2,600,000) Fiscal Year 1995: ¥3,500,000 (Direct Cost: ¥3,500,000)
Keywords	walleye pollack / myosin / amino acid sequence / heavy meromyosin / Edman method / methyl lysine / cDNA cloning / surimi / cDNAクローン / 加工原料 / 筋肉
Research Abstract	We have determined the sequence of 1-1287 amino acids of walleye pollack myosin by cDNA cloning. In this year, the homology between the sequences determined with cDNA and myosin protein, and modified amino acid were investigated. Heavy meromyosin (HMM) was prepared by alpha-chymotryptic digestion of walleye pollack myofibrils and its light chains were removed with urea-acetone. By digestion of HMM with CNBr, lysylendopeptidase, arginylendopeptidase, alpha-chymotrypsin, and trypsin, 6,37,14,6, and 5 peptides, respectively, were obtained. From these peptides, 725 amino acid residues were sequenced by automated Edman method. Accordingly, 355 and 370 residues in S-1 and S-2 regions, respectively, were sequenced. Walleye pollack myosin was found to possess unmodified lysine at the position 35 where the monomethyl lysine exists in chicken myosin and the sequence homology around it is 52-57% to vertebrate myosins. Further, trimethyl lysine was detected at 550 and the homology around it is 71-81%. Moreover, the sequence ^<834>Val-Tyr-Tyr-Lys-Ile-Lys^<839> in the S-2 region waspredicted to be formed beta-sheet structure instead of alpha-helix of carp and rabbit myosins. Existence of two myosin protein isoforms were suggested in adding to two other isoforms of the cDNA clones.