title: Correct post-translational modification and stable vacuolar accumulation of phytohemagglutinin engineered to contain multiple methionine residues.
abstract: Most legume seed storage proteins are deficient in sulfur amino acids. In this study, we demonstrate that replacing specific amino acid residues of a seed protein with methionine residues at positions known to be occupied by methionine residues in homologous proteins, is an effective strategy to create methionine-enriched seed proteins. Mutant phytohemagglutinin polypeptides with three or four methionine residues were found to undergo correct post-translational modifications in transformed cultured tobacco cells and to accumulate stably in the protein storage vacuoles of transgenic tobacco seeds.
authors.affiliation: Department of Biology, University of California, San Diego 92093-0116.
authors.forename: S
authors.initials: S
authors.lastname: Kjemtrup
authors.forename: E M
authors.initials: EM
authors.lastname: Herman
authors.forename: M J
authors.initials: MJ
authors.lastname: Chrispeels
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002478:Cells, Cultured; D018014:Gene Transfer Techniques; D006031:Glycosylation; D046911:Macromolecular Substances; D008715:Methionine; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010835:Phytohemagglutinins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D037121:Plant Lectins; D010947:Plants, Toxic; D017510:Protein Folding; D011499:Protein Processing, Post-Translational; D011993:Recombinant Fusion Proteins; D013329:Structure-Activity Relationship; D014026:Nicotiana; D014617:Vacuoles / Q000378:metabolism*
chemical_list: D046911:Macromolecular Substances; D010835:Phytohemagglutinins; D037121:Plant Lectins; D011993:Recombinant Fusion Proteins; D008715:Methionine