Abstract:
:The hepatic pigment accumulated in 3,5-diethoxycarbonyl-1,4-dihydrocollidine-treated rats, which has been reported to inhibit ferrochelatase, has been isolated and purified. The pigment has been resolved into one major, one minor, and two trace components, all of which appear to be isomeric porphyrins. The major fraction has been unambiguously identified by spectroscopic methods as the isomer of N-methylprotoporphyrin IX (isolated as the dimethyl ester) in which vinyl-substituted pyrrole ring A is methylated. The minor product appears to be an isomer of the same porphyrin with the N-methyl group on propionic acid-substituted ring C, and the trace components have the same high-pressure liquid chromatography retention times as the other two possible isomers of the porphyrin. The four isomers of N-methylprotoporphyrin IX have been chemically synthesized, independently characterized, and used to confirm the structures of the biologically products.
journal_name
Proc Natl Acad Sci U S Aauthors
Ortiz de Montellano PR,Beilan HS,Kunze KLdoi
10.1073/pnas.78.3.1490subject
Has Abstractpub_date
1981-03-01 00:00:00pages
1490-4issue
3eissn
0027-8424issn
1091-6490journal_volume
78pub_type
杂志文章abstract::The AAA-ATPase thyroid hormone receptor interacting protein 13 (TRIP13), jointly with the Mad2-binding protein p31(comet), promotes the inactivation of the mitotic (spindle assembly) checkpoint by disassembling the mitotic checkpoint complex (MCC). This checkpoint system ensures the accuracy of chromosome segregation ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1515358112
更新日期:2015-09-15 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.1315858110
更新日期:2013-12-24 00:00:00
abstract::The crown gall teratoma tumor line BT37, incited by Agrobacterium tumefaciens strain T37, has been found to contain part of the tumor-inducing plasmid, pTi T37, of the inciting strain. This foreign DNA segment, called T-DNA, is maintained at several copies per diploid tumor cell. We have examined subcellular DNA fract...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.77.7.4060
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.1015206108
更新日期:2011-05-10 00:00:00
abstract::The understanding of mechanisms controlling zinc absorption and metabolism at the molecular level has advanced recently. Kinetics of zinc transport have been investigated for many years, but only recently have genes coding for proteins thought to be involved in the transport process been cloned. Four putative zinc tra...
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pub_type: 杂志文章,meta分析,评审
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更新日期:1997-12-23 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1990-06-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1998-02-17 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1990-10-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2020-07-14 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2010-06-29 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1976-11-01 00:00:00