Colour perception in Synechococcus sp. PCC 7002

Mihnev, Aleksandar Valentinov (2021) Colour perception in Synechococcus sp. PCC 7002. PhD thesis, University of Glasgow.

Abstract

[edited]

Cyanobacteriochromes are reversibly photochromic light switches, exclusive to cyanobacteria. Cyanobacteriochromes have a relatively simple yet highly modular structure. At the minimum, these photoreceptors consist of a cGMP-specific phosphodiesterases, adenylyl cyclases and FhlA (GAF) domain with a covalently attached bilin chromophore. In most cases however, these GAF domains can be found in a variety of protein architectures with other sensory and effector domains. The cyanobacteriochrome GAF domain can be tuned to almost any sensitivity in the UV, visible and IR spectra. The ability to measure the makeup of light is likely among the reasons for the incredible biodiversity of cyanobacteria. In this thesis, I have contributed new understanding of cyanobacteriochromes by carrying an in silico analysis on several hundred cyanobacteriochromes and related GAF domains. The final product was a statistical model of the cyanobacteriochrome GAF domain. This model was used to predict the absorption properties of two putative GAF domains from a marine cyanobacterium. One of them, 7GP-03, was experimentally verified via recombinant protein expression and spectral analyses. This protein had an unusual photocyle but with the predicted spectral properties. Subsequent in vivo studies were also carried out with the help of a novel type of bioreactor. These revealed commercially-interesting behavior which was linked to cyanobacteriochrome activity.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Co-supervisors: Prof. Richard Cogdell (University of Glasgow) Dr Douglas McKenzie (Xanthella Inc.)
• Keywords: cyanobacteriochrome, GAF domain, photocycle prediction, bioreactor.
• Subjects: Q Science > QH Natural history > QH301 Biology
• Colleges/Schools: College of Medical Veterinary and Life Sciences > School of Molecular Biosciences
• Supervisor's Name: Amtmann, Professor Anna
• Date of Award: 2021
• Embargo Date: 3 June 2023
• Depositing User: Dr Aleksandar Mihnev
• Unique ID: glathesis:2021-82248
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 03 Jun 2021 18:50
• Last Modified: 05 Apr 2024 10:42
• Thesis DOI: 10.5525/gla.thesis.82248
• URI: https://theses.gla.ac.uk/id/eprint/82248