...
  • 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 >Crystal and cryoEM structural studies of a cell wall degrading enzyme in the bacteriophage φ29 tail
【24h】

Crystal and cryoEM structural studies of a cell wall degrading enzyme in the bacteriophage φ29 tail

机译：噬菌体φ29尾巴中细胞壁降解酶的晶体和cryoEM结构研究

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

The small bacteriophage φ29 must penetrate the ≈250-A thick external peptidoglycan cell wall and cell membrane of the Gram-positive Bacillus subtilis, before ejecting its dsDNA genome through its tail into the bacterial cytoplasm. The tail of bacteriophage φ29 is noncontractile and ≈380 A long. A 1.8-A resolution crystal structure of gene product 13 (gp13) shows that this tail protein has spatially well separated N- and C-terminal domains, whose structures resemble lysozyme-like enzymes and metallo-endopeptidases, respectively. CryoEM reconstructions of the WT bacteriophage and mutant bacteriophages missing some or most of gp13 shows that this enzyme is located at the distal end of the φ29 tail knob. This finding suggests that gp13 functions as a tail-associated, peptidoglycan-degrading enzyme able to cleave both the polysaccharide backbone and peptide cross-links of the peptidoglycan cell wall. Comparisons of the gp13~- mutants with the φ29 mature and emptied phage structures suggest the sequence of events that occur during the penetration of the tail through the peptidoglycan layer.
机译：小型噬菌体φ29必须穿过≈250-A厚的外部肽聚糖细胞壁和革兰氏阳性枯草芽孢杆菌的细胞膜，然后才能通过其尾巴将dsDNA基因组喷射到细菌细胞质中。噬菌体φ29的尾巴没有收缩力，≈380A长。基因产物13（gp13）的1.8-A分辨率晶体结构表明，该尾蛋白具有在空间上充分分离的N和C末端结构域，其结构分别类似于溶菌酶样酶和金属内肽酶。 WT噬菌体和突变体噬菌体的CryoEM重建缺失了gp13的某些或大部分，表明该酶位于φ29尾钮的远端。这一发现表明，gp13起着尾部相关的肽聚糖降解酶的作用，该酶能够裂解肽聚糖细胞壁的多糖主链和肽交联键。比较具有φ29成熟和空噬菌体结构的gp13〜-突变体，表明了在尾巴通过肽聚糖层渗透过程中发生的事件序列。

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