Purification and some properties of high-molecular-weight xylanases, the xylanases 4 and 5 of Aeromonas caviae W-61.
Aeromonas caviae W-61 produces multiple extracellular xylanases, the xylanases 1, 2, 3, 4, and 5 [Nguyen, V. D. et al., Biosci. Biotechnol. Biochem., 56, 1708-1712 (1993)]. Here we purified and characterized high-molecular-weight xylanases, the xylanases 4 and 5 from the culture fluids of the bacterium. The purified xylanases 4 and 5, which had molecular masses of 120 and 140 kDa, respectively, were endo-beta-1,4-xylanases with similar enzymatic properties except for trans-xylosidase activity. The xylanase 4 showed a prominent transxylosidase activity when xylotriose and xylotetraose were used as the substrates, while the xylanase 5 had little transxylosidase activity under the same conditions. Protein sequencing indicated that the xylanase 4 was a C-terminally-truncated xylanase 5, suggesting that the C-terminal truncation of the xylanase 5 may endow the enzyme with transxylosidase activity.
Roy
N
N
Laboratory of Applied Microbiology, Tohoku University Graduate School of Agricultural Science, Sendai, Japan.
Okai
N
N
Tomita
T
T
Muramoto
K
K
Kamio
Y
Y
D000333:Aeromonas / Q000201:enzymology*; D000595:Amino Acid Sequence; D004591:Electrophoresis, Polyacrylamide Gel; D008969:Molecular Sequence Data; D008970:Molecular Weight; D013379:Substrate Specificity; D043325:Xylan Endo-1,3-beta-Xylosidase; D014995:Xylosidases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism
D014995:Xylosidases; D043325:Xylan Endo-1,3-beta-Xylosidase