AN ANALYSIS OF THE EXTRACELLULAR XYLANASES AND CELLULASES OF BUTYRIVIBRIO-FIBRISOLVENS H17C
AN ANALYSIS OF THE EXTRACELLULAR XYLANASES AND CELLULASES OF BUTYRIVIBRIO-FIBRISOLVENS H17C
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DOI：
10.1016/0378-1097(91)90127-v
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发表时间：
1991-11-15
影响因子：
2.1
通讯作者：
THOMSON, JA
中科院分区：
文献类型：
--
作者：
LIN, LL;THOMSON, JA
研究了溶纤维丁酸弧菌H17c胞外木聚糖酶和纤维素酶组分。用羟基磷灰石层析法洗脱了两个主要的酶活性峰，并确定了具有纤维素酶活性的配合物A （C(A)）和主要具有木聚糖酶活性但对羧甲基纤维素（CMC）有一定活性的配合物B （C(B)）。C(B)在DE-52柱上进一步纯化，并进行凝胶过滤。木聚糖酶和CMCase活性呈单峰洗脱，明显分子量大于甲状腺球蛋白（M(r) 669000）。在非变性条件下电泳的聚丙烯酰胺凝胶的CMC氧谱图表明，在C(A)和C(B)中存在5个具有CMCase活性的条带。相同条件下木聚糖氧谱图显示C(B)存在4个活性带。在温和变性条件下，C(B)的木聚糖酶活性在分子质量为45 ~ 180的11条条带上发现，CMCase活性在分子质量为45 ~ 60 kDa的3条条带上发现。这表明C(B)作为木聚糖酶的多亚基蛋白聚集体存在，其中一些也具有纤维素酶活性。
The extracellular xylanase and cellulase components of Butyrivibrio fibrisolvens H17c were investigated. Two major peaks of enzyme activity were eluted by hydroxylapatite chromatography and designated complex A (C(A)), having cellulase activity, and complex B (C(B)) having predominantly xylanase activity but with some activity on carboxymethyl cellulose (CMC). C(B) was further purified on a DE-52 column and subjected to gel filtration. The xylanase and CMCase activities eluted in a single peak with an apparent molecular mass greater than thyroglobulin (M(r) 669000). CMC xymograms of polyacrylamide gels electrophoresed under non-denaturing conditions indicated the presence of five bands with CMCase activity from C(A) and eight from C(B). Xylan xymograms under the same conditions indicated the presence of four bands of activity in C(B). Under mild denaturing conditions the xylanase activity in C(B) was found in 11 bands with molecular mass ranging from 45 to 180 and the CMCase activity in three bands with molecular mass ranging from 45 kDa to 60 kDa. This indicates that C(B) exists as a multi-subunit protein aggregate of xylanases, some of which also have cellulase activity.