Characterization of the GPI-anchored endo β-1,3-glucanase Eng2 of Aspergillus fumigatus

Lukas Hartl (1) , Amandine Gastebois (1) , Vishukumar Aimanianda (1) , Jean-Paul Latge (1)

1 Aspergillus

A GPI-anchored endo β-1,3-glucanase of Aspergillus fumigatus was characterized. The enzyme encoded by ENG2 (AFUA_2g14360) belongs to the glycoside hydrolase family 16 (GH16). The activity was characterized using a recombinant protein produced by Pichiapastoris. The recombinant enzyme preferentially acts on soluble β-1,3-glucans. Enzymatic analysis of the endoglucanase activity using Carboxymethyl-Curdlan-Remazol Brilliant Blue (CM-Curdlan-RBB) as a substrate revealed a wide temperature optimum of 24-40°C, a pH optimum of 5.0-6.5 and a K(m) of 0.8 mg ml(-1). HPAEC analysis of the products formed by Eng2 when acting on different oligo-β-1,3-glucans confirmed the predicted endoglucanase activity and also revealed a transferase activity for oligosaccharides of a low degree of polymerization. The growth phenotype of the Afeng2 mutant was identical to that of the wt strain.

Keywords: Aspergillus fumigatus Cell wall b-1; 3-Glucan Endo b-1; 3-glucanase GPI-anchor ENG2

Domains: Life Sciences [q-bio]; Microbiology and Parasitology; Mycology; Life Sciences [q-bio]; Cellular Biology; Subcellular Processes [q-bio.SC]

Lukas Hartl, Amandine Gastebois, Vishukumar Aimanianda, Jean-Paul Latge. Characterization of the GPI-anchored endo β-1,3-glucanase Eng2 of Aspergillus fumigatus. Fungal Genetics and Biology, 2011, 48 (2), pp.185-191. ⟨10.1016/j.fgb.2010.06.011⟩. ⟨pasteur-02531466⟩