Alkaline purification of spider silk proteins

The method of any of the above claims, wherein the isolated recombinant spider silk protein is a full-length recombinant spider silk protein.

The method of any of the above claims, wherein the purity of the isolated recombinant spider silk protein is 5-10%, 10-15%, 15-20%, 20-25%, 25-30%, 30-35%, 35-40%, 45-50%, 50-55%, 55-60%, 60-65%, 65-70%, 70-75%, 75-80%, 80-85%, 85-90%, 09-95%, or 95-100%.

The method of any of the above claims, wherein the yield of the isolated recombinant spider silk protein is at least 50-55%, 55-60%, 60-65%, 65-70%, 70-75%, 75-80%, 80-85%, 85-90%, 09-95%, or 95-100% as compared to recombinant spider silk isolated by a urea or a guanidine thiocyanate method.

The method of any of the above claims, wherein isolating the recombinant spider silk protein comprises precipitating the recombinant spider silk protein by altering said alkaline conditions of said aqueous solution.

The method of any of the above claims, wherein the portion of said cell culture comprises a supernatant, a whole cell broth, or a cell pellet.

The method of any of the above claims, wherein collecting said portion of said cell culture comprises removing said host cell from said growth medium and reconstituting said host cell in said aqueous solution.

The method of any of the above claims, wherein collecting said portion of said cell culture comprises lysing said host cell.

The method of any of the above claims, wherein said portion of said cell culture comprises said host cell and said growth medium from said cell culture.

The method of any of the above claims, wherein said aqueous solution comprises diluted growth medium.

The method of any of the above claims wherein incubating said portion of said cell culture under alkaline conditions is performed from 10 to 120 minutes.

The method of any of the above claims, wherein incubating said portion of said cell culture under alkaline conditions further comprises agitating the portion of the cell culture.

The method of any of the above claims, further comprising removing an un-solubilized biomass from said aqueous solution under alkaline conditions.

The method of any of the above claims, further comprising removing impurities before isolating the recombinant spider silk protein or after isolating the recombinant spider silk protein.

The method of any of the above claims, further comprising concentrating the isolated recombinant spider silk protein to produce a concentrated spider silk protein.

The method of any of the above claims, further comprising drying the isolated recombinant spider silk protein.

The method of any of the above claims, further comprising generating a silk fiber from the isolated recombinant spider silk.

The method of any of the above claims, wherein said recombinant spider silk protein is 18B or P0.

The method of any of the above claims, wherein the cell culture comprises a fungal, a bacterial or a yeast cell.

The method of any of the above claims, wherein the yeast cell is a Pichia pastoris cell.

A composition comprising a recombinant spider silk protein produced by the method of any one of the above claims.

A composition comprising a cell culture comprising a growth medium and a host cell comprising a recombinant spider silk protein in an alkaline buffer solution.