The construction and characterization of two xylan-degrading chimeric enzymes

Zhanmin Fan, Kurt Wagschal, Charles C. Lee, Que Kong, Katherine A. Shen, Indu B. Maiti, Ling Yuan

Research output: Contribution to journalArticlepeer-review

43 Scopus citations


Degradation of xylan requires several enzymes. Two chimeric enzymes, xyln-ara and xyln-xylo, were constructed by linking the catalytic portion of a xylanase (xyln) to either an arabinofuranosidase (ara) or a xylosidase (xylo) with a flexible peptide linker. The recombinant parental enzymes and chimeras were produced in E. coli at high levels and purified for characterization of their enzymatic and kinetic properties as well as activities on natural substrates. The chimeras closely resemble the parental enzymes or their mixtures with regard to protein properties. They share similar temperature profiles and have similar catalytic efficiencies as the parental enzymes when assayed using substrates 4-nitrophenyl-α-L-arabinofuranoside or 2-nitrophenyl-β-D- xylopyranoside. The chimeras also show unique enzymatic characteristics. In xylanase activity assays using Remazol Brilliant Blue-xylan, while the parental xylanase has a pH optimum of pH 8, the chimeras showed shifted pH optima as a consequence of significantly increased activity at pH 6 (the optimal pH for ara and xylo). Both chimeras exhibited additive effects of the parental enzymes when assayed at wide ranges of pH and temperatures. The xyln-xylo chimera had the same activities as the xyln/xylo mixture in hydrolyzing the natural substrates oat spelt xylan and wheat arabinoxylan. Compared to the xyln/ara mixture, the xyln-ara chimera released the same amounts of xylose from oat spelt xylan and ∼30% more from wheat arabinoxylan at pH 6. Our results demonstrate the feasibility and advantages of generating bifunctional enzymes for the improvement of xylan bioconversion.

Original languageEnglish
Pages (from-to)684-692
Number of pages9
JournalBiotechnology and Bioengineering
Issue number3
StatePublished - Feb 15 2009


  • Bifunctional enzymes
  • Bioenergy
  • Biomass conversion
  • Enzyme engineering

ASJC Scopus subject areas

  • Biotechnology
  • Bioengineering
  • Applied Microbiology and Biotechnology


Dive into the research topics of 'The construction and characterization of two xylan-degrading chimeric enzymes'. Together they form a unique fingerprint.

Cite this