TY - JOUR
T1 - Structural basis of redox modulation on chloroplast ATP synthase
AU - Yang, Jay How
AU - Williams, Dewight
AU - Kandiah, Eaazhisai
AU - Fromme, Petra
AU - Chiu, Po Lin
N1 - Funding Information:
The establishment of the isolation procedure for chloroplast ATP synthase (originally aimed for structure determination by X-ray crystallography) was supported by the National Institute of Health grant (R01GM081490) to P.F. We would like to acknowledge the use of the Titan Krios TEM in the EMC at ASU with the support funding for the instrumentation by NSF MRI 1531991. We thank David Lowry in the EMC at ASU for technical assistance. We also acknowledge the ESRF for the provision of cryo-EM time on CM01. The computation was partly supported by the NVIDIA GPU Grant Program to P.-L.C. The cryo-EM studies were partly supported by the ASU Biodesign Center for Applied Structural Discovery (CASD) and the ASU start-up fund to P.-L.C. We thank Yuval Mazor, Kuang-Lei Tsai, and Debra Hansen for proofreading the article. We thank Shangji Zhang and David Flesher for their assistance in some steps of the protein purification as well as Karie Robertson for designing and producing the graphic art for Figure 5b of the manuscript.
Publisher Copyright:
© 2020, The Author(s).
PY - 2020/12/1
Y1 - 2020/12/1
N2 - In higher plants, chloroplast ATP synthase has a unique redox switch on its γ subunit that modulates enzyme activity to limit ATP hydrolysis at night. To understand the molecular details of the redox modulation, we used single-particle cryo-EM to determine the structures of spinach chloroplast ATP synthase in both reduced and oxidized states. The disulfide linkage of the oxidized γ subunit introduces a torsional constraint to stabilize the two β hairpin structures. Once reduced, free cysteines alleviate this constraint, resulting in a concerted motion of the enzyme complex and a smooth transition between rotary states to facilitate the ATP synthesis. We added an uncompetitive inhibitor, tentoxin, in the reduced sample to limit the flexibility of the enzyme and obtained high-resolution details. Our cryo-EM structures provide mechanistic insight into the redox modulation of the energy regulation activity of chloroplast ATP synthase.
AB - In higher plants, chloroplast ATP synthase has a unique redox switch on its γ subunit that modulates enzyme activity to limit ATP hydrolysis at night. To understand the molecular details of the redox modulation, we used single-particle cryo-EM to determine the structures of spinach chloroplast ATP synthase in both reduced and oxidized states. The disulfide linkage of the oxidized γ subunit introduces a torsional constraint to stabilize the two β hairpin structures. Once reduced, free cysteines alleviate this constraint, resulting in a concerted motion of the enzyme complex and a smooth transition between rotary states to facilitate the ATP synthesis. We added an uncompetitive inhibitor, tentoxin, in the reduced sample to limit the flexibility of the enzyme and obtained high-resolution details. Our cryo-EM structures provide mechanistic insight into the redox modulation of the energy regulation activity of chloroplast ATP synthase.
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U2 - 10.1038/s42003-020-01221-8
DO - 10.1038/s42003-020-01221-8
M3 - Article
C2 - 32879423
AN - SCOPUS:85090144270
VL - 3
JO - Communications Biology
JF - Communications Biology
SN - 2399-3642
IS - 1
M1 - 482
ER -