ENZYMATIC-PROPERTIES OF THE XYLANASE PREPARATION FROM THERMOMYCES-LANUGINOSUS

Xylanase preparation obtained by submersed fermentation of Thermomyces lanuginosus (sample of the commercial xylanase preparation obtained f rom ''Krka'', p.o., Novo Mesto, Slovenia) was characterized. The prepa ration is apparently devoid of other proteins, as shown by SDS-electro phoresis. The enzyme exhibited the highest activity at pH about 7.0, a nd in the temperature range 60-70 degrees C. It was stable for 96 hour s at pH between 5.0 and 9.0, and at temperatures up to 60 degrees C. D ithiobis-2-nitrobenzoic acid, p-hydroxymercuri benzoic acid and Hg2+ i ons completely inhibited the enzyme, while Mn2+, Fe2+ and beta-mercapt oethanol enhanced the xylanase activity.