Functional identification of the cDNA coding for a wheat endo-1,4-beta-D-xylanase inhibitor.
Using expressed sequence tag data, we obtained a full-length cDNA encoding a wheat protein inhibitor of xylanases (XIP-I). The 822 bp open reading frame encoded a protein of 274 amino acids with a molecular mass of 30.2 kDa, in excellent agreement with the native protein. Expression in Escherichia coli confirmed that the cDNA encoded a functional endo-1,4-beta-D-xylanase inhibitor. Its deduced amino acid sequence exhibited highest similarity to sequences classified as class III chitinases, but the inhibitor did not exhibit chitinase activity. This is the first full-length cDNA sequence that encodes a novel class of protein which inhibits the activity of endo-1,4-beta-D-xylanases.
Elliott
Giles O
GO
Institute of Food Research, Norwich Research Park, Norwich, UK.
Hughes
Richard K
RK
Juge
Nathalie
N
Kroon
Paul A
PA
Williamson
Gary
G
D001483:Base Sequence; D003001:Cloning, Molecular; D043364:Endo-1,4-beta Xylanases; D004791:Enzyme Inhibitors / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014908:Triticum / Q000201:enzymology / Q000235:genetics*; D014995:Xylosidases / Q000037:antagonists & inhibitors*
D004791:Enzyme Inhibitors; D010940:Plant Proteins; D011994:Recombinant Proteins; D014995:Xylosidases; D043364:Endo-1,4-beta Xylanases