Riken Corporation

The Institute of Physical and Chemical Research

Other

Japan Science and Technology Agency

Japan Science and Technology Corporation

Akebono Research and Development Center Ltd.

Japan Science and Technology Corporation, and Riken

Yoshiharu Doi

Toshiaki Fukui

Hiromi Matsusaki

Tadahisa Iwata

Hideki Yamane

Seiichi Taguchi

Shojiro Kaita

Zhaomin Hou

Yasuo Wakatsuki

Keiji Numata

Hideki Abe

Hideo Nakashita

Toshihisa Tanaka

Kazuma Takase

Tomoyasu Kichise

Miwa Yamada

Keiko Yoshioka

Isamu Yamaguchi

Satoshi Kusaka

A polyhydroxyalkanoate copolymer of 3HB (3-hydroxybutyrate), 3HP (3-hydroxypropionate) and 5HV (5 -hydroxyvalerate) disclosed. The polyhydroxyalkanoate can be used for bioplastic or biomaterial. A method for producing the polyhydroxyalkanoate comprises culturing a microorganism belonging togenus in a culture medium that comprises lactone and/or hydroxy acid or salt of hydroxy acid as a carbon source.

Method for producing polyhydroxyalkanoate having long main chain structure

A biopolyester which is poly(3-hydroxyalkanoate) or poly(3-hydroxyalkanoate) copolymer and has a reduced calcium content. It has improved thermal stability due to the reduced calcium content.

Thermostable biopolyester

An object of the present invention is to provide: a process for conveniently producing a fiber with high strength, regardless of molecular weight polymer composition, or the like of PHAs, which vary depending on origins such as a wild-type PHAs-producing microorganism product, a genetically modified strain product, and a chemical product; and the fiber with high strength produced through the process. The present invention provides: a process for producing a fiber, comprising: melt-extruding polyhydroxyalkanoic acid to form a melt-extruded fiber; rapidly quenching the melt-extruded fiber to the glass transition temperature of polyhydroxyalkanoic acid +15&#xb0; C. or less, and solidifying the fiber to form an amorphous fiber; forming a crystalline fiber by leaving the amorphous fiber to stand at the glass transition temperature +15&#xb0; C. or less; drawing the crystalline fiber; and further subjecting the crystalline fiber to stretch heat treatment.

High-strength fiber of biodegradable aliphatic polyester and process for producing the same

The present invention is a process for producing a fiber, comprising: melt-extruding polyhydroxyalkanoic acid; solidifying the polyhydroxyalkanoic acid by quenching it to its glass transition temperature +15&#xb0; C. or less, to form an amorphous fiber; cold-drawing the amorphous fiber at its glass transition temperature +20&#xb0; C. or less; and subjecting the fiber to heat treatment under tension. The present invention can provide: a process for producing a fiber with high strength, and the fiber produced through the process; and a process for producing a fiber with high strength and high modulus of elasticity and the fiber with high strength and high modulus of elasticity produced through the process, regardless of molecular weights of PHAs varying depending on origins such as a wild type PHAs-producing microorganism product, a genetically modified product, and a chemical product.

Polyhydroxyalkanoic acid fibers with high strength, fibers with high strength and high modulus of elasticity, and processes for producing the same

Biodegradable polyester with desired physical properties. A mutant poly(3-hydroxyalkanoic acid) synthase comprising an amino acid sequence of (a) or (b) below.

Mutant poly(3-hydroxyalkanoic acid) synthases

There is provided a method for producing a biodegradable polyester capable of controlling various physical properties of the biodegradable polyester. A poly(3-hydroxyalkanoate) biosynthetic enzyme is altered by an evolutionary-engineering technique, and the poly(3-hydroxyalkanoate) biosynthetic enzyme is expressed in a host to synthesize various copolymers in the host.

Method for producing biodegradable polyester

The present invention relates to a catalyst for polymerization of a conjugated diene or the like, which is composed of a metallocene-type cation complex of a gadolinium compound. Examples of such catalyst include a metallocene-type cation complex of a trivalent gadolinium compound represented by the general formula (I): RGdX(wherein, Gd represents gadolinium; R represents a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group, a substituted indenyl group, a fluorenyl group, or a substituted fluorenyl group; X represents an anion; 'a' represents an integer of 1 or 2; and 'b' represents an integer of 1 or 2). The present invention provides a catalyst by which polymerization of a conjugated diene or copolymerization of a conjugated diene and an aromatic vinyl compound can be carried out efficiently and inexpensively.

Polymerization catalyst

A transformant, whose polyhydroxybutanoic acid polymerase gene is disrupted, having a recombinant vector containing a polyester polymerase gene, a &#x3b2;-ketothiolase gene, and a NADPH-acetoacetyl CoA reductase gene.

Method of producing copolymer polyester

The present invention relates to a method for the transformation of a plant characterized by ligating an operon to a vector, the operon containing a promoter and 2-100 genes of interest, and integrating the resulting recombinant vector into a plastid chromosome, to a transformed plant obtained by the method, and the a process for preparing a polyester characterized by culturing or cultivating the transformed plant and collecting the polyester from the cultured or cultivated plant.

Methods for transformation of plants, transformed plants and processes for preparation of polyesters

The present invention relates to a polypeptide comprising the amino acid sequence of SEQ ID NO:1 or an amino acid sequence having one or more amino acids deleted, replaced or added. The polypeptide further comprises polyester synthase activity. The invention further relates to a polyester synthase gene comprising DNA coding for a polypeptide, a recombinant vector comprising the gene, and a transformant transformed with the recombinant vector.

Polyester synthase and a gene coding for the same

The present invention relates to a polypeptide comprising the amino acid sequence of SEQ ID NO:1 or a sequence of SEQ ID NO:1 where in one or more amino acids are deleted, replaced or added, and the polypeptide having polyester synthase activity; a polyester synthase gene comprising DNA coding for the above polypeptide; a recombinant vector comprising the gene; and a transformant transformed with the recombinant vector is also provided.

The present invention relates to a polyester synthase gene coding for a polypeptide containing the amino acid sequence of SEQ ID NO:2 or a sequence where in the amino acid sequence of SEQ ID NO:2, one or more amino acids are deleted, replaced or added, the polypeptide bringing about polyester synthase activity; a gene expression cassette comprising the polyester synthase gene and either of open reading frames located upstream and downstream of the gene; a recombinant vector comprising the gene expression cassette; a transformant transformed with the recombinant vector; and a process for producing polyester by culturing the transformant in a medium and recovering polyester from the resulting culture.

Polyester synthase gene and process for producing polyester

The present invention relates to a polypeptide comprising the amino acid sequence of SEQ ID NO:1 or a sequence of SEQ ID NO:1 where in, one or more amino acids are deleted, replaced or added, and the polypeptide having polyester synthase activity. A polyester synthase gene comprising DNA coding for the above polypeptide; a recombinant vector comprising the gene; and a transformant transformed with the recombinant vector is also provided.

Poly(3-hydroxybutanoic acid) having a number average molecular weight of not less than 500,000 is oriented at a draw ratio of 2-fold or more to reproducibly obtain a film made of poly(3-hydroxybutanoic acid) having biodegradability and biocompatibility as well as sufficient strength and flexibility (for example, tensile strength of not less than 30 MPa and elongation to break of not less than 15%).

Growing community of inventors

Saitama, Japan

Yoshiharu Doi