Cloning and characterization of xylanase A from the strain Bacillus sp. BP-7: comparison with alkaline pI-low molecular weight xylanases of family 11.
The xynA gene encoding a xylanase from the recently isolated Bacillus sp. strain BP-7 has been cloned and expressed in Escherichia coli. Recombinant xylanase A showed high activity on xylans from hardwoods and cereals, and exhibited maximum activity at pH 6 and 60 degrees C. The enzyme remained stable after incubation at 50 degrees C and pH 7 for 3 h, and it was strongly inhibited by Mn(2+), Fe(3+), Pb(2+), and Hg(2+). Analysis of xylanase A in zymograms showed an apparent molecular size of 24 kDa and a pI of above 9. The amino acid sequence of xylanase A, as deduced from xynA gene, shows homology to alkaline pI-low molecular weight xylanases of family 11 such as XynA from Bacillus subtilis. Analysis of codon usage in xynA from Bacillus sp. BP-7 shows that the G+C content at the first and second codon positions is notably different from the mean values found for glycosyl hydrolase genes from Bacillus subtilis.
Gallardo
Oscar
O
Departament de Microbiologia, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 645, 08028 Barcelona, Spain.
Diaz
Pilar
P
Pastor
F I Javier
FI
D001407:Bacillus / Q000201:enzymology*; D001483:Base Sequence; D003001:Cloning, Molecular; D003062:Codon; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry / Q000235:genetics*; D007526:Isoelectric Point; D008969:Molecular Sequence Data; D008970:Molecular Weight
D003062:Codon; D043364:Endo-1,4-beta Xylanases