Otro
cDNA cloning and 1.75 angstrom crystal structure determination of PPL2, an endochitinase and N-acetylglucosamine-binding hemagglutinin from Parkia platycephala seeds
Registro en:
Febs Journal. Oxford: Blackwell Publishing, v. 273, n. 17, p. 3962-3974, 2006.
1742-464X
10.1111/j.1742-4658.2006.0540.x
WOS:000239858300009
Autor
Cavada, Benildo S.
Moreno, Frederico B. B.
da Rocha, Bruno A. M.
de Azevedo, Walter F.
Castellon, Rolando E. R.
Goersch, Georg V.
Nagano, Celso S.
de Souza, Emmanuel P.
Nascimento, Kyria S.
Radis-Baptista, Gandhi
Delatorre, Plinio
Leroy, Yves
Toyama, Marcos H.
Pinto, Vicente P. T.
Sampaio, Alexandre H.
Barettino, Domingo
Debray, Henri
Calvete, Juan J.
Sanz, Libia
Resumen
Parkia platycephala lectin 2 was purified from Parkia platycephala (Leguminosae, Mimosoideae) seeds by affinity chromatography and RP-HPLC. Equilibrium sedimentation and MS showed that Parkia platycephala lectin 2 is a nonglycosylated monomeric protein of molecular mass 29 407 +/- 15 Da, which contains six cysteine residues engaged in the formation of three intramolecular disulfide bonds. Parkia platycephala lectin 2 agglutinated rabbit erythrocytes, and this activity was specifically inhibited by N-acetylglucosamine. In addition, Parkia platycephala lectin 2 hydrolyzed beta(1-4) glycosidic bonds linking 2-acetoamido-2-deoxy-beta-D-glucopyranose units in chitin. The full-lengthamino acid sequence of Parkia platycephala lectin 2, determined by N-terminal sequencing and cDNA cloning, and its three-dimensional structure, established by X-ray crystallography at 1.75 angstrom resolution, showed that Parkia platycephala lectin 2 is homologous to endochitinases of the glycosyl hydrolase family 18, which share the (beta alpha)(8) barrel topology harboring the catalytic residues Asp125, Glu127, and Tyr182.