Abstract：
:Single crystals of disodium beta-glycerophosphate pentahemihydrate (betaGP), Na2x(HO)CH2CH(PO(4)2-)CH2(OH)x5 1/2H2O, were X-irradiated at 77 and 280 K. EPR, ENDOR and FSE techniques were used to study the formation of free radicals in these irradiated crystals to characterize possible reaction mechanisms leading to dephosphorylation. Irradiation at 77 K reveals the presence of four different radicals: two alkoxy radical conformations, AR1 and AR2, (HO)CH2CH(PO(4)2-)CH2O. and two carbon-centered hydroxyalkyl radicals, LTR1, (HO)CH2CH(PO(4)2-) C.HOH, and LTR2, with a tentative structure (HO)CH2C.H(PO(4)2-)CH2OH. AR1 and AR2 were determined to be formed on each of the two independent molecules A and B of the asymmetrical unit of betaGP, each on the 3-end of the molecule. Irradiation at 280 K reveals the presence of three hydroxyalkyl allyl radicals, R1, R2 and R3, with the common chemical structure (HO)C.H-H=CH(OH). Radicals R1 and R2 are determined to form on molecules B and A of the asymmetrical unit, respectively. The site of radical formation for R3 could not be ascertained absolutely from the available data, and there is also evidence that suggests the possibility that R3 has a hydroxyphospho-allyl radical structure. Possible reaction mechanisms for the formation of both the 77 K radicals and the 280 K radicals are suggested and discussed. The formation of an allyl-type radical in such a small-molecule single-crystal model system is an interesting and surprising result which may be relevant to the formation of the so-called 3alphaH radical species commonly observed in irradiated solid cytosine nucleosides and nucleotides. The result is also important because of the formation of the hydroxyalkyl allyl radical in solid beta-glycerophosphate is at variance with mechanisms and products shown to dominate for this and similar systems in solution radiolysis.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Baine TJ,Sagstuen Esubject
Has Abstractpub_date
1998-08-01 00:00:00pages
148-58issue
2eissn
0033-7587issn
1938-5404journal_volume
150pub_type
杂志文章abstract：:The non-random distribution of DNA breakage in PFGE (pulsed-field gel electrophoresis) experiments poses a problem of proper subtraction of the background DNA damage to obtain a fragment-size distribution due to radiation only. A naive bin-to-bin subtraction of the background signal will not result in the right DNA ma...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR0663.1
更新日期：2006-12-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
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更新日期：1997-05-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-11-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1028.1
更新日期：2008-06-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1991-10-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1984-01-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-09-01 00:00:00
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journal_title：Radiation research
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doi：
更新日期：1989-02-01 00:00:00
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journal_title：Radiation research
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更新日期：2016-03-01 00:00:00
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journal_title：Radiation research
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doi：
更新日期：1988-12-01 00:00:00
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journal_title：Radiation research
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更新日期：2007-07-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-01-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
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更新日期：2013-08-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1987-11-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-10-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3430.1
更新日期：2005-10-01 00:00:00
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更新日期：2014-02-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1997-07-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
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更新日期：2016-08-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR3529.1
更新日期：2006-06-01 00:00:00
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journal_title：Radiation research
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更新日期：2013-02-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-08-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1986-03-01 00:00:00
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journal_title：Radiation research
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doi：
更新日期：1988-07-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1984-05-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1993-11-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1986-02-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
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更新日期：2004-12-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1999-09-01 00:00:00
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journal_title：Radiation research
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更新日期：2009-02-01 00:00:00
