Open AccessIdentification in the mould Hypocrea jecorina of a gene encoding an NADP + : d ‐xylose dehydrogenase
Author(s) -
Berghäll Suvi,
Hilditch Satu,
Penttilä Merja,
Richard Peter
Publication year - 2007
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2007.00969.x
Subject(s) - hypocrea , xylose , biochemistry , xylitol , enzyme , trichoderma reesei , dehydrogenase , yeast , chemistry , biology , fermentation , cellulase
A gene coding for an NADP + ‐dependent d ‐xylose dehydrogenase was identified in the mould Hypocrea jecorina ( Trichoderma reesei ). It was cloned from cDNA, the active enzyme was expressed in yeast and a histidine‐tagged enzyme was purified and characterized. The enzyme had highest activity with d ‐xylose and significantly smaller activities with other aldose sugars. The enzyme is specific for NADP + . The K m values for d ‐xylose and NADP + are 43 mM and 250 μM, respectively. The role of this enzyme in H. jecorina is unclear because in this organism d ‐xylose is predominantly catabolized through a path with xylitol and d ‐xylulose as intermediates and the mould is unable to grow on d ‐xylonic acid.