摘要:
Novel signal peptides capable of functioning in yeasts have the amino acid sequence:Met-A.sub.1 -A.sub.2 -X-B-C-D-E-Fwherein A.sub.1 is a peptide chain composed of 1-3 amino acids each selected from the group consisting of Arg, Ser, Lys and His, A.sub.2 is a peptide chain composed of 1-3 amino acids, X is a peptide chain composed of 8-10 hydrophobic amino acids, B is Pro or Ser, C is Gly or Pro, D Cys, Ala, Leu, Ser, Thr and Val, E is Trp or Gln and F is Ala or Gly. DNA sequences coding for these signal peptides can be used for the secretory expression of heterologous proteins in yeasts.
摘要:
A polypropylene thermoplastic resin composition comprising (a) a modified crystalline polypropylene of a crystalline polypropylene comprising said modified crystalline polypropylene and (b) a modified polyamide obtained by partially or wholly grafting a polyamide with a clay mineral. A polypropylene thermoplastic resin composition comprising, in addition to the above polypropylene thermoplastic resin composition comprising the components (a) and (b), one or any combination of the following components (c), (d) and (e): (c) an ethylene-.alpha.-olefin copolymer rubber or a modified ethylene-.alpha.-olefin copolymer rubber, (d) a block copolymer between a monovinyl-substituted aromatic hydrocarbon and a conjugated diene, a hydrogenation product of said block copolymer, or a modification product of said block copolymer, and (e) an inorganic filler. The modified polyamide as the component (b), obtained by modifying a polyamide with a clay mineral has good compatibility with or good dispersibility in the component (a), i.e. the modified crystalline polypropylene or the crystalline polypropylene comprising the modified crystalline polypropylene. Therefore, the polypropylene thermoplastic resin composition comprising these components (a) and (b) has excellent heat resistance and excellent impact resistance.
摘要:
A method for preparing foreign protein in yeast using an expression recombinant DNA comprising DNA encoding the serum albumin signal peptide adjacent to DNA encoding the foreign protein is disclosed.
摘要:
A reinforced polypropylene resin composition contains the following components (A), (B) and (C) in amounts of 67 to 82% by weight of, 6 to 12% by weight and 12 to 21% by weight, respectively:Component (A): crystalline ethylene-propylene block copolymer having an ethylene content of 2 to 4% by weight, a molecular distribution of polypropylene component (Q=M.sub.w /M.sub.n) of at least 7, isotacticity of polypropylene component of at least 98%, an intrinsic viscosity (decalin, 135.degree. C.) of room temperature p-xylene soluble content of at least 6 dl/g, a melt flow rate (MFR) of 3 to 15 g/10 minutes, and the product of flexural modulus at room temperature and Izod impact strength at room temperature of at least 120000.Component (B): at least one elastomer selected from the group of consisting of (a) hydrogenated block copolymer rubbers each comprising block (I) composed of an aromatic vinyl compound copolymer and block (II) composed of a conjugated diene copolymer, and having a bonding structure of I-II or I-(II-I).sub.n (wherein n=1 or 2), wherein block (I) is contained in an amount of 10 to 40% by weight of the copolymer and is hydrogenated in an amount of 10 mol % or less, and block (II) is contained in an amount of 60 to 90% by weight of the copolymer and is hydrogenated in an amount of at least 90 mol %; and (b) ethylene-.alpha.-olefin copolymer rubbers each containing 30 to 95% by weight of ethylene.Component (C): talc having an average particle size of 3 to 5 .mu.m, which is measured by a laser diffraction method, a BET specific surface area of 5 to 13 m.sup.2 /g, and a top cut size of less than 20 .mu.m.
摘要:
A polypropylene thermoplastic resin composition comprising (a) a modified crystalline polypropylene of a crystalline polypropylene comprising said modified crystalline polypropylene and (b) a modified polyamide obtained by partially or wholly grafting a polyamide with a clay mineral. A polypropylene thermoplastic resin composition comprising, in addition to the above polypropylene thermoplastic resin composition comprising the components (a) and (b), one or any combination of the following components (c), (d) and (e): (c) an ethylene-.alpha.-olefin copolymer rubber or a modified ethylene-.alpha.-olefin copolymer rubber, (d) a block copolymer between a monovinyl-substituted aromatic hydrocarbon and a conjugated diene, a hydrogenation product of said block copolymer, or a modification product of said block copolymer, and (e) an inorganic filler. The modified polyamide as the component (b), obtained by modifying a polyamide with a clay mineral has good compatibility with or good dispersibility in the component (a), i.e. the modified crystalline polypropylene or the crystalline polypropylene comprising the modified crystalline polypropylene. Therefore, the polypropylene thermoplastic resin composition comprising these components (a) and (b) has excellent heat resistance and excellent impact resistance.