Effect of Oligosaccharide Degree of Polymerization on the Induction of Xylan-Degrading Enzymes by  Fusarium oxysporum  f. sp.  Lycopersici [Elektronisk resurs]

• Xylan is one of the most abundant carbohydrates on Earth. Complete degradation of xylan is achieved by the collaborative action of endo-β-1,4-xylanases and β-d-xylosidases and a number of accessories enzymes. In filamentous fungi, the xylanolytic system is controlled through induction and repression. However, the exact mechanism remains unclear. Substrates containing xylan promote the induction of xylanases, which release xylooligosaccharides. These, in turn, induce expression of xylanase-encoding genes. Here, we aimed to determine which xylan degradation products acted as inducers, and whether the size of the released oligomer correlated with its induction strength. To this end, we compared xylanase production by different inducers, such as sophorose, lactose, cellooligosaccharides, and xylooligosaccharides in Fusarium oxysporum f. sp. lycopersici. Results indicate that xylooligosaccharides are more effective than other substrates at inducing endoxylanase and β-xylosidases. Moreover, we report a correlation between the degree of xylooligosaccharide polymerization and induction efficiency of each enzyme. Specifically, xylotetraose is the best inducer of endoxylanase, xylohexaose of extracellular β-xylosidase, and xylobiose of cell-bound β-xylosidase. 

Ämnesord

Engineering and Technology  (hsv)

Industrial Biotechnology  (hsv)

Bioprocess Technology  (hsv)

Teknik och teknologier  (hsv)

Industriell bioteknik  (hsv)

Bioprocessteknik  (hsv)

Biokemisk processteknik  (ltu)

Biochemical Process Engineering  (ltu)

Genre

government publication  (marcgt)

Indexterm och SAB-rubrik

xylooligosaccharides

xylanases

induction

Fusarium oxysporum

enzymatic assay