title: Modified 2S albumins with improved tryptophan content are correctly expressed in transgenic tobacco plants.
abstract: Brazil nut 2S albumins lack the essential amino acid tryptophan. In order to improve the protein's nutritional value and create a basis for structural investigations, three separate modified Brazil nut 2S albumin 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 confirmation of the predicted protein structure through fluorescence quenching techniques. The modified genes, under the regulation of the CaMV 35S promoter, were introduced into Nicotiana tabacum. All three modified genes were correctly transcribed and the 2S albumin accumulated in the seeds of transgenic plants.
authors.affiliation: EMBRAPA-CENARGEN S.A.I.N., Brasília DF, Brazil.
authors.forename: L H
authors.initials: LH
authors.lastname: Marcellino
authors.forename: G
authors.initials: G
authors.lastname: Neshich
authors.forename: M F
authors.initials: MF
authors.lastname: Grossi de Sá
authors.forename: E
authors.initials: E
authors.lastname: Krebbers
authors.forename: E S
authors.initials: ES
authors.lastname: Gander
mesh_terms: D016960:Agrobacterium tumefaciens / Q000235:genetics; D000418:Albumins / Q000737:chemistry* / Q000235:genetics; D001483:Base Sequence; D015152:Blotting, Northern; D004797:Enzyme-Linked Immunosorbent Assay; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D007150:Immunohistochemistry; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed / Q000235:genetics; D009754:Nuts / Q000737:chemistry*; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics; D030821:Plants, Genetically Modified / Q000235:genetics*; D010947:Plants, Toxic; D011487:Protein Conformation; D012984:Software; D014026:Nicotiana / Q000235:genetics; D014170:Transformation, Genetic / Q000235:genetics; D014364:Tryptophan / Q000032:analysis* / Q000235:genetics
chemical_list: D000418:Albumins; D010940:Plant Proteins; D014364:Tryptophan