Molecular Effects of Elongation Factor Ts and Trigger Factor on the Unfolding and Aggregation of Elongation Factor Tu Induced by the Prokaryotic Molecular Chaperone Hsp33
Minho Keum,
Dai Ito,
Mi-Seong Kim,
Yuxi Lin,
Kyeong-Hyeon Yoon,
Jihoon Kim,
Sung-Hee Lee,
Ji-Hun Kim,
Wookyung Yu,
Young-Ho Lee,
Hyung-Sik Won
Affiliations
Minho Keum
Department of Biotechnology, Research Institute (RIBHS) and College of Biomedical and Health Science, Konkuk University, Chungju 27478, Korea
Dai Ito
Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Korea
Mi-Seong Kim
Department of Biotechnology, Research Institute (RIBHS) and College of Biomedical and Health Science, Konkuk University, Chungju 27478, Korea
Yuxi Lin
Research Center of Bioconvergence Analysis, Korea Basic Science Institute, Ochang, Cheongju 28119, Korea
Kyeong-Hyeon Yoon
Department of Biotechnology, Research Institute (RIBHS) and College of Biomedical and Health Science, Konkuk University, Chungju 27478, Korea
Jihoon Kim
Department of Biotechnology, Research Institute (RIBHS) and College of Biomedical and Health Science, Konkuk University, Chungju 27478, Korea
Sung-Hee Lee
College of Pharmacy, Chungbuk National University, Cheongju 28160, Korea
Ji-Hun Kim
College of Pharmacy, Chungbuk National University, Cheongju 28160, Korea
Wookyung Yu
Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, Korea
Young-Ho Lee
Research Center of Bioconvergence Analysis, Korea Basic Science Institute, Ochang, Cheongju 28119, Korea
Hyung-Sik Won
Department of Biotechnology, Research Institute (RIBHS) and College of Biomedical and Health Science, Konkuk University, Chungju 27478, Korea
Hsp33, a prokaryotic redox-regulated holding chaperone, has been recently identified to be able to exhibit an unfoldase and aggregase activity against elongation factor Tu (EF-Tu) in its reduced state. In this study, we investigated the effect of elongation factor Ts (EF-Ts) and trigger factor (TF) on Hsp33-mediated EF-Tu unfolding and aggregation using gel filtration, light scattering, circular dichroism, and isothermal titration calorimetry. We found that EF-Tu unfolding and subsequent aggregation induced by Hsp33 were evident even in its complex state with EF-Ts, which enhanced EF-Tu stability. In addition, although TF alone had no substantial effect on the stability of EF-Tu, it markedly amplified the Hsp33-mediated EF-Tu unfolding and aggregation. Collectively, the present results constitute the first example of synergistic unfoldase/aggregase activity of molecular chaperones and suggest that the stability of EF-Tu is modulated by a sophisticated network of molecular chaperones to regulate protein biosynthesis in cells under stress conditions.
