A comprehensive assessment of environmental ultraviolet radiation induced DNA damage in marine microorganisms
There is evidence that ultraviolet radiation (UVR) is increasing over certain locations on the Earth's surface. Of primary concern is the annual pattern of ozone depletion over Antarctica and the Southern Ocean. Reduction of ozone concentration selectively limits absorption of solar UV-B (290–3...
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fttexasmc:oai:digitalcommons.library.tmc.edu:dissertations-1130 2023-11-05T03:33:49+01:00 A comprehensive assessment of environmental ultraviolet radiation induced DNA damage in marine microorganisms Meador, Jarah A 2004-01-01T08:00:00Z https://digitalcommons.library.tmc.edu/dissertations/AAI3138884 ENG eng DigitalCommons@TMC https://digitalcommons.library.tmc.edu/dissertations/AAI3138884 Texas Medical Center Dissertations (via ProQuest) Environmental science|Molecular biology|Microbiology text 2004 fttexasmc 2023-10-10T11:18:10Z There is evidence that ultraviolet radiation (UVR) is increasing over certain locations on the Earth's surface. Of primary concern is the annual pattern of ozone depletion over Antarctica and the Southern Ocean. Reduction of ozone concentration selectively limits absorption of solar UV-B (290–320 nm), resulting in higher irradiance at the Earth's surface. The effects of ozone depletion on the human population and natural ecosystems, particularly the marine environment, are a matter of considerable concern. Indeed, marine plankton may serve as sensitive indicators of ozone depletion and UV-B fluctuations. Direct biological effects of UVR result from absorption of UV-B by DNA. Once absorbed, energy is dissipated by a variety of pathways, including covalent chemical reactions leading to the formation of photoproducts. The major types of photoproduct formed are cyclobutyl pyrimidine dimer (CPD) and pyrimidine(6-4)pyrimidone dimer [(6-4)PD]. Marine plankton repair these photoproducts using light-dependent photoenzymatic repair or nucleotide excision repair. The studies here show that fluctuations in CPD concentrations in the marine environment at Palmer Station, Antarctica correlate well with ozone concentration and UV-B irradiance at the Earth's surface. A comparison of photoproduct levels in marine plankton and DNA dosimeters show that bacterioplankton display higher resistance to solar UVR than phytoplankton in an ozone depleted environment. DNA damage in marine microorganisms was investigated during two separate latitudinal transects which covered a total range of 140°. We observed the same pattern of change in DNA damage levels in dosimeters and marine plankton as measured using two distinct quantitative techniques. Results from the transects show that differences in photosensitivity exist in marine plankton collected under varying UVR environments. Laboratory studies of Antarctic bacterial isolates confirm that marine bacterioplankton possess differences in survival, DNA damage induction, and repair following ... Text Antarc* Antarctic Antarctica Southern Ocean Houston Academy of Medicine-Texas Medical Center (HAM-TMC): DigitalCommons@The Texas Medical Center |
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Houston Academy of Medicine-Texas Medical Center (HAM-TMC): DigitalCommons@The Texas Medical Center |
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fttexasmc |
language |
English |
topic |
Environmental science|Molecular biology|Microbiology |
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Environmental science|Molecular biology|Microbiology Meador, Jarah A A comprehensive assessment of environmental ultraviolet radiation induced DNA damage in marine microorganisms |
topic_facet |
Environmental science|Molecular biology|Microbiology |
description |
There is evidence that ultraviolet radiation (UVR) is increasing over certain locations on the Earth's surface. Of primary concern is the annual pattern of ozone depletion over Antarctica and the Southern Ocean. Reduction of ozone concentration selectively limits absorption of solar UV-B (290–320 nm), resulting in higher irradiance at the Earth's surface. The effects of ozone depletion on the human population and natural ecosystems, particularly the marine environment, are a matter of considerable concern. Indeed, marine plankton may serve as sensitive indicators of ozone depletion and UV-B fluctuations. Direct biological effects of UVR result from absorption of UV-B by DNA. Once absorbed, energy is dissipated by a variety of pathways, including covalent chemical reactions leading to the formation of photoproducts. The major types of photoproduct formed are cyclobutyl pyrimidine dimer (CPD) and pyrimidine(6-4)pyrimidone dimer [(6-4)PD]. Marine plankton repair these photoproducts using light-dependent photoenzymatic repair or nucleotide excision repair. The studies here show that fluctuations in CPD concentrations in the marine environment at Palmer Station, Antarctica correlate well with ozone concentration and UV-B irradiance at the Earth's surface. A comparison of photoproduct levels in marine plankton and DNA dosimeters show that bacterioplankton display higher resistance to solar UVR than phytoplankton in an ozone depleted environment. DNA damage in marine microorganisms was investigated during two separate latitudinal transects which covered a total range of 140°. We observed the same pattern of change in DNA damage levels in dosimeters and marine plankton as measured using two distinct quantitative techniques. Results from the transects show that differences in photosensitivity exist in marine plankton collected under varying UVR environments. Laboratory studies of Antarctic bacterial isolates confirm that marine bacterioplankton possess differences in survival, DNA damage induction, and repair following ... |
format |
Text |
author |
Meador, Jarah A |
author_facet |
Meador, Jarah A |
author_sort |
Meador, Jarah A |
title |
A comprehensive assessment of environmental ultraviolet radiation induced DNA damage in marine microorganisms |
title_short |
A comprehensive assessment of environmental ultraviolet radiation induced DNA damage in marine microorganisms |
title_full |
A comprehensive assessment of environmental ultraviolet radiation induced DNA damage in marine microorganisms |
title_fullStr |
A comprehensive assessment of environmental ultraviolet radiation induced DNA damage in marine microorganisms |
title_full_unstemmed |
A comprehensive assessment of environmental ultraviolet radiation induced DNA damage in marine microorganisms |
title_sort |
comprehensive assessment of environmental ultraviolet radiation induced dna damage in marine microorganisms |
publisher |
DigitalCommons@TMC |
publishDate |
2004 |
url |
https://digitalcommons.library.tmc.edu/dissertations/AAI3138884 |
genre |
Antarc* Antarctic Antarctica Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctica Southern Ocean |
op_source |
Texas Medical Center Dissertations (via ProQuest) |
op_relation |
https://digitalcommons.library.tmc.edu/dissertations/AAI3138884 |
_version_ |
1781701491617169408 |