...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of bacteriology >Effects of disruption of xylanase-encoding genes on the xylanolytic system of Streptomyces lividans.
【24h】

Effects of disruption of xylanase-encoding genes on the xylanolytic system of Streptomyces lividans.

机译：木聚糖酶编码基因的破坏对链霉菌木聚糖分解系统的影响。

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Wild-type Streptomyces lividans produced the three xylanases (XlnA, XlnB, and XlnC) when xylan, xylan hydrolysates obtained by the action of XlnA, XlnB, and XlnC, or purified small xylo-oligosaccharides (xylobiose [X2], xylotriose [X3], xylotetraose [X4], and xylopentaose [X5]) were used as the carbon source. The three xylanase genes of S. lividans (xlnA, xlnB, and xlnC) were disrupted by using vectors that integrate into the respective genes. Disruption of one or more of the xln genes resulted in reduced growth rates and reduced total xylanase activities when the strain was grown in xylan. The greatest effect was observed when xlnA was disrupted. In medium containing xylan, disruption of xlnA did not affect expression of xlnB and xlnC; disruption of xlnB did not affect expression of xlnA but affected expression of xlnC; and disruption of xlnC did not affect expression of xlnA but affected expression of xlnB. A fraction of XlnB or XlnC hydrolytic products (those with a degree of polymerization greater than 11 [X11]) was found to stimulate expression of xlnB and xlnC in strains disrupted in xlnC and xlnB, respectively, whereas lower-molecular-weight fractions as well as purified small xylo-oligosaccharides did not. The stimulating molecule(s) lost its effect when it was hydrolyzed further by XlnA. A mechanism of transglycosylation reactions by the S. lividans xylanases is postulated to be involved in the regulation of xln genes.
机译：当通过XlnA，XlnB和XlnC的作用获得的木聚糖，木聚糖水解物或纯化的小木糖寡糖（木糖[X2]，木三糖[X3]）时，野生型Lividans野生型链霉菌产生了三种木聚糖酶（XlnA，XlnB和XlnC）。 ，木糖四糖[X4]和木糖戊糖[X5]用作碳源。紫葡萄链球菌的三个木聚糖酶基因（xlnA，xlnB和xlnC）通过使用整合到各个基因中的载体而被破坏。当该菌株在木聚糖中生长时，一个或多个xln基因的破坏导致生长速率降低和木聚糖酶总活性降低。当xlnA被破坏时，观察到最大的效果。在含有木聚糖的培养基中，破坏xlnA不会影响xlnB和xlnC的表达。 xlnB的破坏不影响xlnA的表达，但影响xlnC的表达。 xlnC的破坏不会影响xlnA的表达，但会影响xlnB的表达。发现一部分XlnB或XlnC水解产物（聚合度大于11 [X11]的那些）分别刺激xlnC和xlnB破坏的菌株中xlnB和xlnC的表达，而低分子量馏分也是如此因为纯化的小木糖低聚糖没有。当XlnA进一步水解该刺激分子时，其失去作用。假定由S.lividans木聚糖酶进行的转糖基化反应的机制涉及xln基因的调节。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号