...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >A MEMBRANE-ASSOCIATED FORM OF SUCROSE SYNTHASE AND ITS POTENTIAL ROLE IN SYNTHESIS OF CELLULOSE AND CALLOSE IN PLANTS
【24h】

A MEMBRANE-ASSOCIATED FORM OF SUCROSE SYNTHASE AND ITS POTENTIAL ROLE IN SYNTHESIS OF CELLULOSE AND CALLOSE IN PLANTS

机译：膜合成形式的蔗糖合酶及其在植物纤维素和蔗糖合成中的作用

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Sucrose synthase (SuSy; EC 2.4.1.13; sucrose + UDP reversible arrow UDPglucose + fructose) has always been studied as a cytoplasmic enzyme in plant cells where it serves to degrade sucrose and provide carbon for respiration and synthesis of cell wall polysaccharides and starch, We report here that at least half of the total SuSy of developing cotton fibers (Gossypium hirsutum) is tightly associated with the plasma membrane. Therefore, this form of SuSy might serve to channel carbon directly from sucrose to cellulose and/or callose synthases in the plasma membrane. By using detached and permeabilized cotton fibers, we show that carbon from sucrose can be converted at high rates to both cellulose and callose, Synthesis of cellulose or callose is favored by addition of EGTA or calcium and cellobiose, respectively, These findings contrast with the. traditional observation that when UDPglucose is used as substrate in vitro, callose is the major product synthesized. Immunolocalization studies show that SuSy can be localized at the fiber surface in patterns consistent with the deposition of cellulose or callose, Thus, these results support a model in which SuSy exists in a complex with the beta-glucan synthases and serves to channel carbon from sucrose to glucan. [References: 47]
机译：蔗糖合酶（SuSy; EC 2.4.1.13;蔗糖+ UDP可逆箭头UDP葡萄糖+果糖）一直被研究为植物细胞中的细胞质酶，可降解蔗糖并为呼吸作用和细胞壁多糖和淀粉的合成提供碳，我们在此报告，发育中的棉纤维（陆地棉）的总SuSy至少有一半与质膜紧密相关。因此，这种形式的SuSy可能用于将碳从蔗糖直接引导到质膜中的纤维素和/或call质合酶。通过使用分离和透化的棉纤维，我们显示出蔗糖中的碳可以高速率转化为纤维素和，糖。分别添加EGTA或钙和纤维二糖有利于纤维素或ose糖的合成，这些发现与相反。传统观察表明，当将UDP葡萄糖用作体外底物时，call糖是合成的主要产物。免疫定位研究表明SuSy可以以与纤维素或call质沉积一致的方式定位在纤维表面，因此，这些结果支持了一个模型，其中SuSy与β-葡聚糖合酶复合存在，并用于引导蔗糖中的碳葡聚糖。 [参考：47]

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