K. Sakka et al., PURIFICATION AND CHARACTERIZATION OF XYLANASE A FROM CLOSTRIDIUM-STERCORARIUM F9 AND A RECOMBINANT ESCHERICHIA-COLI, Bioscience, biotechnology, and biochemistry, 58(8), 1994, pp. 1496-1499
Xylanase A encoded by the Clostridium stercorarium F-9 xynA gene was p
urified to homogeneity from a recombinant clone of Escherichia coli. T
he N-terminal amino acid sequence and molecular weight (54,000) estima
ted by SDS-PAGE of the purified enzyme were consistent with those dedu
ced from the nucleotide sequence [Biosci. Biotech. Biochem., 57, 273-2
77 (1993)]. A xylanase was also purified to homogeneity from a culture
supernatant of C. stercorarium F-9. Its N-terminal amino acid sequenc
e, molecular weight, and enzymatic properties were quite in agreement
with those of the recombinant enzyme, indicating that the xynA gene wa
s predominantly expressed as a xylanase gene in C. stercorarium F-9. T
he purified enzyme hydrolyzed xylotriose to yield xylobiose and xylose
while it was less active toward xylobiose. It was optimally active at
75 degrees C and pH 7.0. K-m and V-max were estimated to be 1.9 mg/ml
and 2.8 mu mol of xylose equivalent/min/mu g for oat spelt xylan, res
pectively.