Differential expression of three alpha-galactosidase genes and a single beta-galactosidase gene from Aspergillus niger

A gene encoding a third alpha-galactosidase (AglB) from Aspergillus niger has been cloned and sequenced. An alignment of AglB amino acid sequence with alpha-galatosidases revealed that it belongs to a family of alpha-galatosidases that also includes A. niger AglA. The expression of the genes aglA, aglB, aglC and lacA was studied using monomeric, oligomeric and polymeric compounds as growth substrates. All four genes have distinct expression patterns which seem to mirror the natural substrates of the encoded proteins.