The present inventors confirmed that when a brazzein expression recombinant vector for high expression of brazzein in Saccharomyces cerevisiae was prepared and a S. cerevisiae strain Y2805 was transformed with the recombinant vector, the expression level of brazzein was particularly high, thereby completing an optimal expression system for mass-producing brazzein. Further, when the brazzein expression system is cultured under the optimal culture conditions according to the present invention, the amount of brazzein produced is further increased, the purification process is simple, and costs are reduced. Therefore, it is expected that the brazzein expression system according to the present invention can be widely used for mass-producing and commercializing brazzein, which is a sweet protein.

The present inventors confirmed that when a brazzein expression recombinant vector for high expression of brazzein in Saccharomyces cerevisiae was prepared and a S. cerevisiae strain Y2805 was transformed with the recombinant vector, the expression level of brazzein was particularly high, thereby completing an optimal expression system for mass-producing brazzein. Further, when the brazzein expression system is cultured under the optimal culture conditions according to the present invention, the amount of brazzein produced is further increased, the purification process is simple, and costs are reduced. Therefore, it is expected that the brazzein expression system according to the present invention can be widely used for mass-producing and commercializing brazzein, which is a sweet protein.

An intracellular selection system allows screening for peptide bioactivity and stability. Randomized recombinant peptides are screened for bioactivity in a tightly regulated expression system, preferably derived from the wild-type lac operon. Bioactive peptides thus identified are inherently protease- and peptidase-resistant. Also provided are bioactive peptides stabilized by a stabilizing group at the N-terminus, the C-terminus, or both. The stabilizing group can be a small stable protein, such as the Rop protein, glutathione sulfotransferase, thioredoxin, maltose binding protein, or glutathione reductase, an -helical moiety, or one or more proline residues.

An intracellular selection system allows screening for peptide bioactivity and stability. Randomized recombinant peptides are screened for bioactivity in a tightly regulated expression system, preferably derived from the wild-type lac operon. Bioactive peptides thus identified are inherently protease- and peptidase-resistant. Also provided are bioactive peptides stabilized by a stabilizing group at the N-terminus, the C-terminus, or both. The stabilizing group can be a small stable protein, such as the Rop protein, glutathione sulfotransferase, thioredoxin, maltose binding protein, or glutathione reductase, an -helical moiety, or one or more proline residues.

Disclosed is a thermoconductive material comprising a protein and having a thermal conductivity of more than 0.6 W/(m.Math.K). Also disclosed is a method for producing a thermoconductive material comprising a protein at least a part of which forms crystalline -pleated sheets, the crystalline -pleated sheets being present in an amount of 10% by weight or more, based on the total weight of the protein, and the thermoconductive material having a thermal conductivity of more than 0.6 W/(m.Math.K), the method comprising dissolving a raw material protein in a formic acid solution containing calcium chloride to obtain a protein solution, and evaporating the formic acid from the protein solution.

Disclosed is a thermoconductive material comprising a protein and having a thermal conductivity of more than 0.6 W/(m.Math.K). Also disclosed is a method for producing a thermoconductive material comprising a protein at least a part of which forms crystalline -pleated sheets, the crystalline -pleated sheets being present in an amount of 10% by weight or more, based on the total weight of the protein, and the thermoconductive material having a thermal conductivity of more than 0.6 W/(m.Math.K), the method comprising dissolving a raw material protein in a formic acid solution containing calcium chloride to obtain a protein solution, and evaporating the formic acid from the protein solution.

The present inventors confirmed that when a brazzein expression recombinant vector for high expression of brazzein in Saccharomyces cerevisiae was prepared and a S. cerevisiae strain Y2805 was transformed with the recombinant vector, the expression level of brazzein was particularly high, thereby completing an optimal expression system for mass-producing brazzein. Further, when the brazzein expression system is cultured under the optimal culture conditions according to the present invention, the amount of brazzein produced is further increased, the purification process is simple, and costs are reduced. Therefore, it is expected that the brazzein expression system according to the present invention can be widely used for mass-producing and commercializing brazzein, which is a sweet protein.

The present inventors confirmed that when a brazzein expression recombinant vector for high expression of brazzein in Saccharomyces cerevisiae was prepared and a S. cerevisiae strain Y2805 was transformed with the recombinant vector, the expression level of brazzein was particularly high, thereby completing an optimal expression system for mass-producing brazzein. Further, when the brazzein expression system is cultured under the optimal culture conditions according to the present invention, the amount of brazzein produced is further increased, the purification process is simple, and costs are reduced. Therefore, it is expected that the brazzein expression system according to the present invention can be widely used for mass-producing and commercializing brazzein, which is a sweet protein.

The invention provides a method for the production of soybean embryogenic callus and somatic embryos. The invention further provides methods of transforming explants that includes generating somatic embryo tissue. The transgenic somatic embryos produced can be used for regenerating stable transgenic plants.

The invention provides a method for the production of soybean embryogenic callus and somatic embryos. The invention further provides methods of transforming explants that includes generating somatic embryo tissue. The transgenic somatic embryos produced can be used for regenerating stable transgenic plants.