A method of molecular self-assembly is disclosed using two interacting streams that are allowed to interact and are subsequently forced through an orifice. A first stream of a dope solution of polymer molecules is extruded out of a capillary. The dope stream is surrounded by a focusing fluid which is miscible with the dope solution. The interaction between the jet of dope solution and surrounding focusing fluid creates hydrodynamic stretching and allows for extracting solvent from the dope solution. Concentrated polymers within the solution at stretched regions of the jet interact, and finally self-assembly takes place after the fluids are forced through the outlet of a converging nozzle. The formation of the structure can be optionally completed in a coagulating space. The structures thus obtained such as fibers or threads can be wound onto a mandrel.

A method of molecular self-assembly is disclosed using two interacting streams that are allowed to interact and are subsequently forced through an orifice. A first stream of a dope solution of polymer molecules is extruded out of a capillary. The dope stream is surrounded by a focusing fluid which is miscible with the dope solution. The interaction between the jet of dope solution and surrounding focusing fluid creates hydrodynamic stretching and allows for extracting solvent from the dope solution. Concentrated polymers within the solution at stretched regions of the jet interact, and finally self-assembly takes place after the fluids are forced through the outlet of a converging nozzle. The formation of the structure can be optionally completed in a coagulating space. The structures thus obtained such as fibers or threads can be wound onto a mandrel.

An object of the present invention is to provide a method for producing a modified fibroin multifilament excellent in productivity and a multifilament produced by the same. The multifilament of the present invention contains modified fibroin, in which the multifilament has 100 or more constituent single yarns, a coefficient of variation in elastic modulus is 15% or less, a coefficient of variation in strength is 15% or less, and a coefficient of variation in elongation is less than 33%.

An object of the present invention is to provide a method for producing a modified fibroin multifilament excellent in productivity and a multifilament produced by the same. The multifilament of the present invention contains modified fibroin, in which the multifilament has 100 or more constituent single yarns, a coefficient of variation in elastic modulus is 15% or less, a coefficient of variation in strength is 15% or less, and a coefficient of variation in elongation is less than 33%.

Provided are a composite molding composition such as a composite film and a composite fiber that have properties such as an improved tensile strength, strain and toughness as a result of blending a peptide or polyamino acid having a β-sheet structure with a natural or artificially modified fibroin-derived protein; a method for producing such composite molding composition; and a method for improving the physical properties of a composite molding composition containing a fibroin-derived protein.

Provided are a composite molding composition such as a composite film and a composite fiber that have properties such as an improved tensile strength, strain and toughness as a result of blending a peptide or polyamino acid having a β-sheet structure with a natural or artificially modified fibroin-derived protein; a method for producing such composite molding composition; and a method for improving the physical properties of a composite molding composition containing a fibroin-derived protein.

A production method of a protein composition, the method comprising a step of hydrolyzing an ester group by bringing a raw material composition containing an esterified protein into contact with an acidic or basic medium.

A production method of a protein composition, the method comprising a step of hydrolyzing an ester group by bringing a raw material composition containing an esterified protein into contact with an acidic or basic medium.

The present disclosure is directed to systems and methods for synthesizing a spidroin. In some embodiments, the methods comprise synthesizing a monomer in vivo in a heterologous host, the monomer comprising an N-terminus IntC domain and a C-terminus IntN domain, and post-translationally polymerizing the synthesized monomer via in vitro split-intein mediated polymerization.

The present disclosure is directed to systems and methods for synthesizing a spidroin. In some embodiments, the methods comprise synthesizing a monomer in vivo in a heterologous host, the monomer comprising an N-terminus IntC domain and a C-terminus IntN domain, and post-translationally polymerizing the synthesized monomer via in vitro split-intein mediated polymerization.