期刊
PROTEIN SCIENCE
卷 21, 期 2, 页码 268-+出版社
WILEY-BLACKWELL
DOI: 10.1002/pro.2013
关键词
protein unfolding; AAA plus proteolytic machine; ATP-dependent denaturation; ranking unfolding power
资金
- Marie Curie Grant [PIRG-GA-2009-256401]
- BSF [2009405]
- NIH [AI-15706, AI-16892]
AAA+ proteases employ a hexameric ring that harnesses the energy of ATP binding and hydrolysis to unfold native substrates and translocate the unfolded polypeptide into an interior compartment for degradation. What determines the ability of different AAA+ enzymes to unfold and thus degrade different native protein substrates is currently uncertain. Here, we explore the ability of the E. coli Lon protease to unfold and degrade model protein substrates beginning at N-terminal, C-terminal, or internal degrons. Lon has historically been viewed as a weak unfoldase, but we demonstrate robust and processive unfolding/degradation of some substrates with very stable protein domains, including mDHFR and titinI27. For some native substrates, Lon is a more active unfoldase than related AAA+ proteases, including ClpXP and ClpAP. For other substrates, this relationship is reversed. Thus, unfolding activity does not appear to be an intrinsic enzymatic property. Instead, it depends on the specific protease and substrate, suggesting that evolution has diversified rather than optimized the protein unfolding activities of different AAA+ proteases.
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