Enzymatic Properties of the Xylanase Preparation from Thermomyces lanuginosus

摘要

Xylanase preparation obtained by submersed fermentation of Thermomyces lanuginosus (sample of the commercial xylanase preparation obtained from »Krka« , p.o., Novo Mesto, Slovenia) was characterized. The preparation is apparently devoid of other proteins, as shown by SDS-electrophoresis. The enzyme exhibited the highest activity at pH about 7.0, and in the temperature range 60-70℃. It was stable for 96 hours at pH between 5.0 and 9.0, and at temperatures up to 60℃. Dithiobis-2-nitrobenzoic acid, p-hydroxym-ercuri benzoic acid and Hg~(2+) ions completely inhibited the enzyme, while Mn~(2+), Fe~(2+) and β-mercaptoethanol enhanced the xylanase activity.%Provedena je karakterizacija preparata ksilanaze dobivenog iz podloge za uzgoj plijesni Thermomyces lanuginosus (komercijalni preparat »Krke« , p.o., Novo Mesto, Slovenija). SDS elektroforeza je pokazala da u preparatu nema drugih vidljivih proteinskih vrpci. Enzim je pokazivao najveću aktivnost pri pH oko 7.0 i u rasponu temperatura 60-70℃. Bio je stabilan 96 sati pri pH između 5.0 i 9.0, te na temperaturama do 60℃. Ditiobis-2-nitrobenzojeva kiselina, p-hidroksimerkuribenzojeva kiselina i Hg~(2+) ioni potpuno su inhibirali enzim, dok su Mn~(2+) ioni, Fe~(2+) ioni i β-mer-kaptoetanol pojačavali aktivnost ksilanaze.