AtFXG1, an Arabidopsis gene encoding alpha-L-fucosidase active against fucosylated xyloglucan oligosaccharides

Plant Physiol. 2002 Jan;128(1):247-55.

Abstract

An alpha-L-fucosidase (EC 3.2.1.51) able to release the t-fucosyl residue from the side chain of xyloglucan oligosaccharides has been detected in the leaves of Arabidopsis plants. Moreover, an alpha-L-fucosidase with similar substrate specificity was purified from cabbage (Brassica oleracea) leaves to render a single band on SDS-PAGE. Two peptide sequences were obtained from this protein band, and they were used to identify an Arabidopsis gene coding for an alpha-fucosidase that we propose to call AtFXG1. In addition, an Arabidopsis gene with homology with known alpha-L-fucosidases has been also found, and we proposed to name it as AtFUC1. Both AtFXG1 and ATFUC1 were heterologously expressed in Pichia pastoris cells and the alpha-L-fucosidase activities secreted to the culture medium. The alpha-L-fucosidase encoded by AtFXG1 was active against the oligosaccharides from xyloglucan XXFG as well as against 2'-fucosyl-lactitol but not against p-nitrophenyl-alpha-L-fucopyranoside. However, the AtFUC1 heterologously expressed was active only against 2'-fucosyl-lactitol. Thus, the former must be related to xyloglucan metabolism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / enzymology*
  • Arabidopsis / genetics
  • Brassica / enzymology*
  • Brassica / genetics
  • Gene Expression Regulation, Enzymologic
  • Glucans*
  • Glycosides / metabolism
  • Molecular Sequence Data
  • Plant Leaves / enzymology*
  • Plant Leaves / genetics
  • Polysaccharides / metabolism*
  • Sequence Homology, Amino Acid
  • Substrate Specificity
  • Xylans*
  • alpha-L-Fucosidase / genetics
  • alpha-L-Fucosidase / isolation & purification
  • alpha-L-Fucosidase / metabolism*

Substances

  • Glucans
  • Glycosides
  • Polysaccharides
  • Xylans
  • 4-nitrophenylfucoside
  • xyloglucan
  • alpha-L-Fucosidase