1
|
Raics K, Pirisi K, Zhuang B, Fekete Z, Kis-Bicskei N, Pecsi I, Ujfalusi KP, Telek E, Li Y, Collado JT, Tonge PJ, Meech SR, Vos MH, Bodis E, Lukacs A. Photocycle alteration and increased enzymatic activity in genetically modified photoactivated adenylate cyclase OaPAC. J Biol Chem 2023; 299:105056. [PMID: 37468104 PMCID: PMC10448171 DOI: 10.1016/j.jbc.2023.105056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/30/2023] [Accepted: 07/11/2023] [Indexed: 07/21/2023] Open
Abstract
Photoactivated adenylate cyclases (PACs) are light activated enzymes that combine blue light sensing capacity with the ability to convert ATP to cAMP and pyrophosphate (PPi) in a light-dependent manner. In most of the known PACs blue light regulation is provided by a blue light sensing domain using flavin which undergoes a structural reorganization after blue-light absorption. This minor structural change then is translated toward the C-terminal of the protein, inducing a larger conformational change that results in the ATP conversion to cAMP. As cAMP is a key second messenger in numerous signal transduction pathways regulating various cellular functions, PACs are of great interest in optogenetic studies. The optimal optogenetic device must be "silent" in the dark and highly responsive upon light illumination. PAC from Oscillatoria acuminata is a very good candidate as its basal activity is very small in the dark and the conversion rates increase 20-fold upon light illumination. We studied the effect of replacing D67 to N, in the blue light using flavin domain. This mutation was found to accelerate the primary electron transfer process in the photosensing domain of the protein, as has been predicted. Furthermore, it resulted in a longer lived signaling state, which was formed with a lower quantum yield. Our studies show that the overall effects of the D67N mutation lead to a slightly higher conversion of ATP to cAMP, which points in the direction that by fine tuning the kinetic properties more responsive PACs and optogenetic devices can be generated.
Collapse
Affiliation(s)
- Katalin Raics
- Department of Biophysics, Medical School, University of Pecs, Pecs, Hungary
| | - Katalin Pirisi
- Department of Biophysics, Medical School, University of Pecs, Pecs, Hungary
| | - Bo Zhuang
- Laboratoire d'Optique et Biosciences, Ecole Polytechnique, Palaiseau, France
| | - Zsuzsanna Fekete
- Department of Biophysics, Medical School, University of Pecs, Pecs, Hungary
| | | | - Ildiko Pecsi
- Department of Biophysics, Medical School, University of Pecs, Pecs, Hungary
| | | | - Elek Telek
- Department of Biophysics, Medical School, University of Pecs, Pecs, Hungary
| | - Yin Li
- Department of Physics, School of Physics and Materials Science, Nanchang University, Nanchang City, China
| | | | - Peter J Tonge
- Department of Chemistry, Stony Brook University, New York, USA
| | | | - Marten H Vos
- Laboratoire d'Optique et Biosciences, Ecole Polytechnique, Palaiseau, France
| | - Emoke Bodis
- Department of Biophysics, Medical School, University of Pecs, Pecs, Hungary.
| | - Andras Lukacs
- Department of Biophysics, Medical School, University of Pecs, Pecs, Hungary.
| |
Collapse
|