Identification and characterization of the α- l-arabinofuranosidase B of Fusarium oxysporum f. sp. dianthi

• Published in: Physiological and molecular plant pathology 2004-04, Vol.64 (4), p.201-208
• Main Authors: Chacón-Martínez, Carlos A., Anzola, Juan M., Rojas, Andrés, Hernández, Freddy, Junca, Howard, Ocampo, Walter, Del Portillo, Patricia
• Format: Article
• Language: English
• Subjects: alpha-N-arabinofuranosidase; amino acid sequences; Arabinase; Biological and medical sciences; Carnation; enzyme activity; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; fungal proteins; Fusarium oxysporum; Fusarium oxysporum f. sp. dianthi; Fusarium wilt; gene expression regulation; Hemicellulase; molecular sequence data; nucleotide sequences; O-glycoside hydrolases; open reading frames; Phytopathogenic fungus; Phytopathology. Animal pests. Plant and forest protection; plant pathogenic fungi; recombinant fusion proteins; sequence analysis; transcription (genetics); α- l-arabinofuranosidase
• ISSN: 0885-5765; 1096-1178
• DOI: 10.1016/j.pmpp.2004.08.005

The gene encoding α- l-Arabinofuranosidase B ( abfB) from the phytopathogenic fungus Fusarium oxysporum f. sp. dianthi ( Fod) was identified, cloned, sequenced and heterologously expressed. AbfB consists in an intronless open reading frame of 1500-bp coding for a protein of 499 aminoacid residues. The partially purified fusion protein has an apparent molecular mass of approximately 58 kDa and exhibits α- l-arabinofuranosidase activity. The specific activity of the recombinant enzyme was 1.07 units mg −1 protein. Optimal activity is attained at pH 4.0 and 50 °C. Interestingly, the abfB gene is actively transcribed in carnation plants infected with Fod. Its upregulation during the infection process suggests a possible role of this gene as virulence factor in the phytopathogenicity of this fungus.