MODIFIED 2S ALBUMINS WITH IMPROVED TRYPTOPHAN CONTENT ARE CORRECTLY EXPRESSED IN TRANSGENIC TOBACCO PLANTS

Brazil nut 2S albumins lack the essential amino acid tryptophan, In or der to improve the protein's nutritional value and create a basis for structural investigations, three separate modified Brazil nut 2S album in genes were constructed, The first mutant contains five consecutive tryptophan codons, while the other two modified genes encode proteins carrying single tryptophan residues at sites that will allow confirmat ion of the predicted protein structure through fluorescence quenching techniques, The modified genes, under the regulation of the CaMV 35S p romoter, were introduced into Nicotiana tabacum, All three modified ge nes were correctly transcribed and the 2S albumin accumulated in the s eeds of transgenic plants.