Full metadata
Title
DNA based artificial light-harvesting antenna
Description
Scientists around the world have been striving to develop artificial light-harvesting antenna model systems for energy and other light-driven biochemical applications. Among the various approaches to achieve this goal, one of the most promising is the assembly of structurally well-defined artificial light-harvesting antennas based on the principles of structural DNA nanotechnology. DNA has recently emerged as an extremely efficient material to organize molecules such as fluorophores and proteins on the nanoscale. It is desirable to develop a hybrid smart material by combining artificial antenna systems based on DNA with natural reaction center components, so that the material can be engineered to convert light energy to chemical energy via formation of a charge-separated state.
Presented here are a series of studies toward this goal. First, self-assembled seven-helix DNA bundles (7HB) with cyclic arrays of three distinct chromophores were developed. The spectral properties and energy transfer mechanisms in the artificial light-harvesting antenna were studied extensively using steady-state and time-resolved methods. Next, engineered cysteine residues in the reaction center of the purple photosynthetic bacterium Rhodobacter sphaeroides were each covalently conjugated to fluorophores in order to explore the spectral requirements for energy transfer between an artificial light harvesting system and the reaction center. Finally, a structurally well-defined and spectrally tunable artificial light-harvesting system was constructed, where multiple organic dyes were conjugated to 3-arm DNA nanostructure. A reaction center protein isolated from the purple photosynthetic bacterium Rhodobacter sphaeroides was linked to one end of the 3-arm junction to serve as the final acceptor, which converts the photonic energy absorbed by the chromophores into chemical energy by charge separation. This type of model system is required to understand how parameters such as geometry, spectral characteristics of the dyes, and conformational flexibility affect energy transfer, and can be used to inform the development of more complex model light-harvesting systems.
Presented here are a series of studies toward this goal. First, self-assembled seven-helix DNA bundles (7HB) with cyclic arrays of three distinct chromophores were developed. The spectral properties and energy transfer mechanisms in the artificial light-harvesting antenna were studied extensively using steady-state and time-resolved methods. Next, engineered cysteine residues in the reaction center of the purple photosynthetic bacterium Rhodobacter sphaeroides were each covalently conjugated to fluorophores in order to explore the spectral requirements for energy transfer between an artificial light harvesting system and the reaction center. Finally, a structurally well-defined and spectrally tunable artificial light-harvesting system was constructed, where multiple organic dyes were conjugated to 3-arm DNA nanostructure. A reaction center protein isolated from the purple photosynthetic bacterium Rhodobacter sphaeroides was linked to one end of the 3-arm junction to serve as the final acceptor, which converts the photonic energy absorbed by the chromophores into chemical energy by charge separation. This type of model system is required to understand how parameters such as geometry, spectral characteristics of the dyes, and conformational flexibility affect energy transfer, and can be used to inform the development of more complex model light-harvesting systems.
Date Created
2014
Contributors
- Dutta, Palash Kanti (Author)
- Liu, Yan (Thesis advisor)
- Yan, Hao (Thesis advisor)
- Chen, Julian (Committee member)
- Gould, Ian (Committee member)
- Arizona State University (Publisher)
Topical Subject
Resource Type
Extent
x, 191 p. : ill. (mostly col.)
Language
eng
Copyright Statement
In Copyright
Primary Member of
Peer-reviewed
No
Open Access
No
Handle
https://hdl.handle.net/2286/R.I.25958
Statement of Responsibility
by Palash Kanti Dutta
Description Source
Retrieved on Dec. 17, 2014
Level of coding
full
Note
thesis
Partial requirement for: Ph.D., Arizona State University, 2014
bibliography
Includes bibliographical references
Field of study: Chemistry
System Created
- 2014-10-01 08:04:08
System Modified
- 2021-08-30 01:32:35
- 3 years 2 months ago
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