Identification of secreted proteins of Aspergillus oryzae associated with growth on solid cereal substrates

Filamentous growth of Aspergillus oryzae on solid cereal substrates involves secretion of substrate converting enzymes and a solid substrate specific polarised hyphal growth phenotype. To identify proteins produced under these specific conditions, the extracts of A. oryzae grown on wheat-based media were analysed using N-terminal sequence analysis. In a submerged wheat-based growth medium of A. oryzae, besides α-amylase, also an arabinosidase and xylanase were abundantly produced. In the extracts of A. oryzae grown on wheat-based solid substrate besides α-amylase and chitinase, two new proteins of 16 and 27 kDa were identified. These hypothetical proteins showed only close homologies to filamentous fungal proteins.