Abstract：
:Copper(II), in the presence of UV-B radiation (280-315 nm), can generate single-strand breaks in the sugar-phosphate backbone of pBR322 plasmid DNA. A low level of single-strand backbone breaks occurs in the presence of Cu(II) alone, but UV-B irradiation increases the rate by the more than 100-fold. Concomitant with the damage to the DNA backbone is a loss of transforming activity. Oxygen is required for generation of the single-strand breaks but not for the loss of transforming activity. A DNA glycosylase (Fpg), which participates in the repair of certain DNA nitrogenous base damage, does not repair plasmid DNA damaged by Cu(II). The hydroxyl radical scavenging compound DMSO is only somewhat effective at protecting the physical and biological properties of the DNA. These results with Cu(II) are compared to those obtained previously with pBR322 plasmid DNA in the presence of Fe(III) and UV-A.
journal_name
Photochem Photobioljournal_title
Photochemistry and photobiologyauthors
Lloyd RE,Larson RA,Adair TL,Tuveson RWdoi
10.1111/j.1751-1097.1993.tb02964.xsubject
Has Abstractpub_date
1993-06-01 00:00:00pages
1011-7issue
6eissn
0031-8655issn
1751-1097journal_volume
57pub_type
杂志文章abstract：:Exposure of cultured MRC5 human fibroblasts or NCTC 2544 human keratinocytes to mild doses of ultraviolet A (UVA: 320-400 nm) radiations markedly decreased the actin reactivity with fluorescein-labeled phalloidin. This indicates a change in the degree of polymerization of actin and thus in the organization of actin fi...
journal_title：Photochemistry and photobiology
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pub_type： 杂志文章
doi：10.1111/j.1751-1097.1993.tb02928.x
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更新日期：2000-10-01 00:00:00
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journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1994.tb05147.x
更新日期：1994-12-01 00:00:00
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journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1997.tb08603.x
更新日期：1997-03-01 00:00:00
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journal_title：Photochemistry and photobiology
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更新日期：2009-11-01 00:00:00
