- The beta-1,4-endogalactanase A gene from Aspergillus niger is specifically induced on arabinose and galacturonic acid and plays an important role in the degradation of pectic hairy regions. De Vries, R.P., Parenicová, L., Hinz, S.W., Kester, H.C., Beldman, G., Benen, J.A., Visser, J. Eur. J. Biochem. (2002)