Rotary properties of hybrid F1-ATPases consisting of subunits from different species

Ryo R Watanabe; Busra Tas Kiper; Mariel Zarco-Zavala; Mayu Hara; Ryohei Kobayashi; Hiroshi Ueno; José J García-Trejo; Chun-Biu Li; Hiroyuki Noji

doi:10.1016/j.isci.2023.106626

Rotary properties of hybrid F₁-ATPases consisting of subunits from different species

iScience. 2023 Apr 8;26(5):106626. doi: 10.1016/j.isci.2023.106626. eCollection 2023 May 19.

Authors

Ryo R Watanabe¹, Busra Tas Kiper², Mariel Zarco-Zavala¹, Mayu Hara¹, Ryohei Kobayashi¹, Hiroshi Ueno¹, José J García-Trejo³, Chun-Biu Li², Hiroyuki Noji¹

Affiliations

¹ Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan.
² Department of Mathematics, Stockholm University, 106 91 Stockholm, Sweden.
³ Department of Biology, Chemistry Faculty, National Autonomous University of Mexico, Mexico 04510, Mexico.

Abstract

F₁-ATPase (F₁) is an ATP-driven rotary motor protein ubiquitously found in many species as the catalytic portion of F_oF₁-ATP synthase. Despite the highly conserved amino acid sequence of the catalytic core subunits: α and β, F₁ shows diversity in the maximum catalytic turnover rate V_max and the number of rotary steps per turn. To study the design principle of F₁, we prepared eight hybrid F₁s composed of subunits from two of three genuine F₁s: thermophilic Bacillus PS3 (TF₁), bovine mitochondria (bMF₁), and Paracoccus denitrificans (PdF₁), differing in the V_max and the number of rotary steps. The V_max of the hybrids can be well fitted by a quadratic model highlighting the dominant roles of β and the couplings between α-β. Although there exist no simple rules on which subunit dominantly determines the number of steps, our findings show that the stepping behavior is characterized by the combination of all subunits.

Keywords: Biophysics; Cell biology; Structural biology.