期刊
FRONTIERS IN PHYSIOLOGY
卷 12, 期 -, 页码 -出版社
FRONTIERS MEDIA SA
DOI: 10.3389/fphys.2021.804646
关键词
bacterial secretion systems; secretion signal; ABC transporter; amphipathic helix; ATPase activity; protein secretion
类别
The toxin hemolysin A is secreted by a dedicated secretion machinery in uropathogenic E. coli strains. This machinery, consisting of TolC, HlyD and HlyB proteins, belongs to the Type I secretion system family. Researchers proposed an amphipathic helix in the C-terminal region of the toxin that plays a crucial role in the early steps of secretion.
The toxin hemolysin A was first identified in uropathogenic E. coli strains and shown to be secreted in a one-step mechanism by a dedicated secretion machinery. This machinery, which belongs to the Type I secretion system family of the Gram-negative bacteria, is composed of the outer membrane protein TolC, the membrane fusion protein HlyD and the ABC transporter HlyB. The N-terminal domain of HlyA represents the toxin which is followed by a RTX (Repeats in Toxins) domain harboring nonapeptide repeat sequences and the secretion signal at the extreme C-terminus. This secretion signal, which is necessary and sufficient for secretion, does not appear to require a defined sequence, and the nature of the encoded signal remains unknown. Here, we have combined structure prediction based on the AlphaFold algorithm together with functional and in silico data to examine the role of secondary structure in secretion. Based on the presented data, a C-terminal, amphipathic helix is proposed between residues 975 and 987 that plays an essential role in the early steps of the secretion process.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据