title: Characterization of a saccharide-binding protein from Talisia esculenta seeds with trypsin inhibitory activity.
abstract: Some proteins exhibit characteristics that suggest they have a primary, if not an exclusive role in nutrient reserve storage. The best studied examples are the storage proteins that accumulate specifically in developing seeds. Some of these protein demonstrate biological activities that could contribute to resistance to pest, pathogens or abiotic stresses. In this study we present the biochemical characterization and cloning of the major protein from seeds of T. esculenta (Talisin), a member of the Sapindaceae family. The N-terminal sequence of the protein isolated was used to produce a degenerated primer. This primer allowed the amplification of the Talisin cDNA by RTPCR from mRNA of the T. esculenta seeds protein. The sequence analysis of the cloned cDNA, demonstrated a 756 bp sequence encoding a peptide of 198 amino acids. The deduced peptide presented high similarity to a typical VSP, the 22-kDa protein in lychee (73 %) and 50.0 % identity to Theobroma bicolor reserve protein. Identities of 52.0 % and 44.0 % to trypsin inhibitors from Treobroma mammosum and Populus tremula respectively. In conclusion, we may suggest that Talisin could be a seed storage protein with affinity properties, i.e. interacts with carbohydrates and trypsin enzyme.
authors.affiliation: Departamento de Tecnologia de Alimentos, Centro de Ciências Biológicas, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil.
authors.forename: Maria das Graças M
authors.initials: Md
authors.lastname: Freire
authors.forename: Ilka Maria
authors.initials: IM
authors.lastname: Vasconcelos
authors.forename: Marcos Vinïcius
authors.initials: MV
authors.lastname: Oliveira
authors.forename: Gonçalo Apolinário de Souza
authors.initials: GA
authors.lastname: Filho
authors.forename: Maria Lïgia R
authors.initials: ML
authors.lastname: Macedo
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D008969:Molecular Sequence Data; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D029631:Sapindaceae / Q000235:genetics / Q000378:metabolism*; D012639:Seeds / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D014361:Trypsin Inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D011956:Receptors, Cell Surface; D014361:Trypsin Inhibitors; C055213:saccharide-binding proteins