A xylanase produced by the rumen anaerobic protozoan Polyplastron multivesiculatum shows close sequence similarity to family 11 xylanases from gram-positive bacteria.
We report for the first time the cloning and characterisation of a protozoal enzyme involved in plant cell wall polysaccharide degradation. A cDNA library was constructed from the ruminal protozoan Polyplastron multivesiculatum and a stable clone expressing xylanase activity was isolated. The encoded enzyme belongs to the glycoside hydrolase family 11, and phylogenetic analysis indicates a closer relationship with catalytic domains from Gram-positive bacteria than the other fibrolytic eukaryotes from the rumen, the anaerobic fungi.
Devillard
E
E
Rowett Research Institute, Bucksburn, Aberdeen, UK.
Newbold
C J
CJ
Scott
K P
KP
Forano
E
E
Wallace
R J
RJ
Jouany
J P
JP
Flint
H J
HJ
D000595:Amino Acid Sequence; D000693:Anaerobiosis; D000818:Animals; D001483:Base Sequence; D016798:Ciliophora / Q000201:enzymology* / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D005936:Glucans / Q000378:metabolism; D006094:Gram-Positive Bacteria / Q000201:enzymology / Q000235:genetics; D015151:Immunoblotting; D008969:Molecular Sequence Data; D010802:Phylogeny; D012417:Rumen / Q000469:parasitology*; D017422:Sequence Analysis, DNA; D043325:Xylan Endo-1,3-beta-Xylosidase; D014990:Xylans / Q000378:metabolism; D014995:Xylosidases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
D018076:DNA, Complementary; D005936:Glucans; D014990:Xylans; D014995:Xylosidases; D043325:Xylan Endo-1,3-beta-Xylosidase