title: Crystallization and preliminary X-ray diffraction analysis of the seed lectin from Parkia platycephala.
abstract: The crystallization and preliminary X-ray diffraction analysis of the seed lectin of Parkia platycephala, a Mimosoideae, regarded as the most primitive group of the Leguminosae plants, are reported. Its amino-acid sequence consists of three tandemly arranged jacalin-related beta-prism domains, which is a novel fold for a leguminous lectin. Furthermore, no other lectin structure with this arrangement of domains has been described. P2(1)2(1)2(1) crystals (unit-cell parameters a = 63.6, b = 68.5, c = 208.5 A), which diffract to a maximum resolution of 2.2 A, were obtained in hanging drops at pH 8 and 293 K by the vapor-diffusion method using 10% 2-propanol and 20% polyethylene glycol 4000 as precipitants. The asymmetric unit contains two lectin molecules and has a solvent content of 46%. Only a single beta-prism domain could be located by molecular replacement using the structure of the Helianthus tuberosus lectin (PDB code 1c3k) as the search model. Isomorphous heavy-atom derivatives are currently being produced to solve the complete structure of the P. platycephala seed lectin.
authors.affiliation: Instituto de Biomedicina de Valencia, CSIC, Jaime Roig 11, E-46010 Valencia, Spain.
authors.forename: Francisca
authors.initials: F
authors.lastname: Gallego del Sol
authors.forename: Santiago
authors.initials: S
authors.lastname: Ramón-Maiques
authors.forename: Claudia F
authors.initials: CF
authors.lastname: Santos
authors.forename: Thalles B
authors.initials: TB
authors.lastname: Grangeiro
authors.forename: Celso S
authors.initials: CS
authors.lastname: Nagano
authors.forename: Creuza M S A
authors.initials: CM
authors.lastname: Farias
authors.forename: Benildo S
authors.initials: BS
authors.lastname: Cavada
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Calvete
mesh_terms: D003460:Crystallization; D018360:Crystallography, X-Ray; D007887:Fabaceae / Q000737:chemistry* / Q000196:embryology; D037102:Lectins / Q000737:chemistry*; D037121:Plant Lectins; D011487:Protein Conformation; D012639:Seeds / Q000737:chemistry*
chemical_list: D037102:Lectins; D037121:Plant Lectins