Influence of a family 29 carbohydrate binding module on the activity of galactose oxidase from Fusarium graminearum

Filip Mollerup, Kirsti Parikka, Thu V. Vuong, Maija Tenkanen, Emma Master*

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

12 Citations (Scopus)
242 Downloads (Pure)


Background Galactose oxidase (GaO) selectively oxidizes the primary hydroxyl of galactose to a carbonyl, facilitating targeted chemical derivatization of galactose-containing polysaccharides, leading to renewable polymers with tailored physical and chemical properties. Here we investigate the impact of a family 29 glucomannan binding module on the activity and binding of GaO towards various polysaccharides. Specifically, CBM29-1-2 from Piromyces equi was separately linked to the N- and C-termini of GaO. Results Both GaO-CBM29 and CBM29-GaO were successfully expressed in Pichia pastoris, and demonstrated enhanced binding to galactomannan, galactoglucomannan and galactoxyloglucan. The position of the CBM29 fusion affected the enzyme function. Particularly, C-terminal fusion led to greatest increases in galactomannan binding and catalytic efficiency, where relative to wild-type GaO, kcat/Km values increased by 7.5 and 19.8 times on guar galactomannan and locust bean galactomannan, respectively. The fusion of CBM29 also induced oligomerization of GaO-CBM29. Major conclusions Similar to impacts of cellulose-binding modules associated with cellulolytic enzymes, increased substrate binding impeded the action of GaO fusions on more concentrated preparations of galactomannan, galactoglucomannan and galactoxyloglucan; this was especially true for GaO-CBM29. Given the N-terminal positioning of the native galactose-binding CBM32 in GaO, the varying impacts of N-terminal versus C-terminal fusion of CBM29-1-2 may reflect competing action of neighboring CBMs. General significance This study thoroughly examines and discusses the effects of CBM fusion to non-lignocellulytic enzymes on soluble polysaccharides. Herein kinetics of GaO on galactose containing polysaccharides is presented for the first time.

Original languageEnglish
Pages (from-to)354-362
Number of pages9
JournalBiochimica et Biophysica Acta: General Subjects
Issue number2
Publication statusPublished - 1 Feb 2016
MoE publication typeA1 Journal article-refereed


  • Carbohydrate binding module
  • Fusion proteins
  • Galactoglucomannan
  • Galactomannan
  • Galactose oxidase
  • Galactoxyloglucan


Dive into the research topics of 'Influence of a family 29 carbohydrate binding module on the activity of galactose oxidase from Fusarium graminearum'. Together they form a unique fingerprint.

Cite this