5ZWL

Crystal structure of the gamma - epsilon complex of photosynthetic cyanobacterial F1-ATPase

Summary for 5ZWL

• Entry DOI: 10.2210/pdb5zwl/pdb
• Descriptor: ATP synthase epsilon chain, ATP synthase gamma chain (3 entities in total)
• Functional Keywords: atp synthase gamma epsilon cyanobacteria redox regulation, hydrolase
• Biological source: Thermosynechococcus elongatus (strain BP-1); More
• Total number of polymer chains: 2
• Total formula weight: 45865.67

Authors

Murakami, S.,Yamashita, E.,Hisabori, T. (deposition date: 2018-05-16, release date: 2018-09-26, Last modification date: 2024-03-27)

Primary citation

Murakami, S.,Kondo, K.,Katayama, S.,Hara, S.,Sunamura, E.I.,Yamashita, E.,Groth, G.,Hisabori, T.
Structure of the gamma-epsilon complex of cyanobacterial F1-ATPase reveals a suppression mechanism of the gamma subunit on ATP hydrolysis in phototrophs.
Biochem. J., 475:2925-2939, 2018

PubMed Abstract: F-ATPase forms the membrane-associated segment of FF-ATP synthase - the fundamental enzyme complex in cellular bioenergetics for ATP hydrolysis and synthesis. Here, we report a crystal structure of the central F subcomplex, consisting of the rotary shaft γ subunit and the inhibitory ε subunit, from the photosynthetic cyanobacterium BP-1, at 1.98 Å resolution. In contrast with their homologous bacterial and mitochondrial counterparts, the γ subunits of photosynthetic organisms harbour a unique insertion of 35-40 amino acids. Our structural data reveal that this region forms a β-hairpin structure along the central stalk. We identified numerous critical hydrogen bonds and electrostatic interactions between residues in the hairpin and the rest of the γ subunit. To elaborate the critical function of this β-hairpin in inhibiting ATP hydrolysis, the corresponding domain was deleted in the cyanobacterial F subcomplex. Biochemical analyses of the corresponding αβγ complex confirm that the clinch of the hairpin structure plays a critical role and accounts for a significant interaction in the αβ complex to induce ADP inhibition during ATP hydrolysis. In addition, we found that truncating the β-hairpin insertion structure resulted in a marked impairment of the interaction with the ε subunit, which binds to the opposite side of the γ subunit from the β-hairpin structure. Combined with structural analyses, our work provides experimental evidence supporting the molecular principle of how the insertion region of the γ subunit suppresses F rotation during ATP hydrolysis.

PubMed: 30054433
DOI: 10.1042/BCJ20180481

Experimental method

X-RAY DIFFRACTION (1.98 Å)