The elucidation of origin of rotor in rotary ATPase/synthases by functional and structural analysis

2014 Fiscal Year Final Research Report

• Project/Area Number: 24370059
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Functional biochemistry
• Research Institution: Kyoto Sangyo University
• Principal Investigator: YOKOYAMA Ken 京都産業大学, 総合生命科学部, 教授 (70271377)
• Co-Investigator(Kenkyū-buntansha): IMADA Katsumi 大阪大学, 理学研究科, 教授 (40346143)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: bioenergetics / V-ATPase / FoF1 / ATP synthase / molecular motor / molecular evolution / flagellar motor / rotary motor

Outline of Final Research Achievements

In this study, we revealed that FliJ of bacterial flagella motor is possibly an origin of the rotor in rotary ATPase/synthase such as V- or F-ATPases. Actually, FliJ shows a rotor like function in A3B3 based on both biochemical and structural analysis. This strongly suggests that the rotor domains of the rotary ATPases and the flagellar export apparatus share a common evolutionary origin. Domain-swapped chimeric V1 consisting of both T. thermophilus and E. hirae enzymes were generated. Analysis for these enzymes indicated that the interaction between the nucleotide binding and C-terminal domains of the catalytic A subunit critical in reduction of the ADP inhibition. Based on the reconstituted experiments, we proposed a model in which the relationship between V1-DF and Vo-C corresponds to that between a slotted screwdriver and a head of slotted screw, consistent with our previous result in which the central rotor apparatus is not the major factor for the association of V1 with Vo.

Free Research Field

生化学、生物物理学、構造生物学