德国马克斯普朗克研究所Manajit Hayer-Hartl等研究人员发现Rubisco激活酶具有双重功能。相关论文于2020年9月25日在线发表在《细胞》杂志上。
Title: Dual Functions of a Rubisco Activase in Metabolic Repair and Recruitment to Carboxysomes
Author: Mirkko Flecken, Huping Wang, Leonhard Popilka, F. Ulrich Hartl, Andreas Bracher, Manajit Hayer-Hartl
Issue&Volume: 2020-09-25
Abstract: Rubisco, the key enzyme of CO2 fixation in photosynthesis, is prone to inactivation by inhibitory sugar phosphates.Inhibited Rubisco undergoes conformational repair by the hexameric AAA+ chaperoneRubisco activase (Rca) in a process that is not well understood. Here, we performeda structural and mechanistic analysis of cyanobacterial Rca, a close homolog of plantRca. In the Rca:Rubisco complex, Rca is positioned over the Rubisco catalytic siteunder repair and pulls the N-terminal tail of the large Rubisco subunit (RbcL) intothe hexamer pore. Simultaneous displacement of the C terminus of the adjacent RbcLopens the catalytic site for inhibitor release. An alternative interaction of Rcawith Rubisco is mediated by C-terminal domains that resemble the small Rubisco subunit.These domains, together with the N-terminal AAA+ hexamer, ensure that Rca is packagedwith Rubisco into carboxysomes. The cyanobacterial Rca is a dual-purpose protein withfunctions in Rubisco repair and carboxysome organization.
DOI: 10.1016/j.cell.2020.09.010
Source: https://www.cell.com/cell/fulltext/S0092-8674(20)31151-X#%20