Abstract:
:A proton NMR method is described for determining the orientation of a porphyrin within the heme pocket of a hemoprotein. The pattern of the hyperfine-shifted heme methyl resonances in low-spin ferric model compounds is demonstrated to characteristically reflect the position of a localized low-symmetry perturbation on the pi system. The specific assignments via deuteration of the two interconvertible sets of methyl resonances observed for deuteroporphyrin-reconstituted sperm whale metmyoglobin cyanide lead to the conclusion that the low-symmetry perturbations on the heme due to the apo-protein contacts differ for the two protein components by a 180 degrees rotation about the alpha-gamma meso axis. Hence the heme in the reconstituted myoglobin is "disordered" in solution, and the altered functional properties of the reconstituted protein cannot be simply attributed to the local effect of the heme substituent. This NMR technique has applicability for determining the relative heme orientation in related hemoproteins, and may clarify the origin of doubling of heme resonances observed in several native hemoproteins.
journal_name
Proc Natl Acad Sci U S Aauthors
La Mar GN,Budd DL,Viscio DB,Smith KM,Langry KCdoi
10.1073/pnas.75.12.5755subject
Has Abstractpub_date
1978-12-01 00:00:00pages
5755-9issue
12eissn
0027-8424issn
1091-6490journal_volume
75pub_type
杂志文章abstract::Prolyl hydroxylase and other enzymes of collagen synthesis have been found in cloned cells, including epithelium, melanoma, liver, HeLa, pituitary, kidney, and neuroblastoma. The significance of collagen biosynthesis in nonfibroblastic cells lines is discussed. ...
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.71.1.50
更新日期:1974-01-01 00:00:00
abstract::Monoclonal antibodies penetrate bulky tumors poorly after intravenous administration, in part because of specific binding to the target antigen. Experiments presented here demonstrate an analogous phenomenon in micrometastases; poor antibody penetration, attributable to a "binding-site barrier" phenomenon, can be seen...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.92.19.8999
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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.1508990112
更新日期:2015-06-30 00:00:00
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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
doi:10.1073/pnas.95.24.14447
更新日期:1998-11-24 00:00:00
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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
doi:10.1073/pnas.94.17.8976
更新日期:1997-08-19 00:00:00
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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
doi:10.1073/pnas.1932554100
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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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doi:10.1073/pnas.0904890106
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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:2010-09-07 00:00:00
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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
doi:10.1073/pnas.0603900103
更新日期:2006-07-11 00:00:00
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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:1997-12-09 00:00:00
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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
doi:10.1073/pnas.72.4.1594
更新日期:1975-04-01 00:00:00
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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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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.93.23.12926
更新日期:1996-11-12 00:00:00
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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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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1972-01-01 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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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
doi:10.1073/pnas.84.12.4180
更新日期:1987-06-01 00:00:00
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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
doi:10.1073/pnas.79.2.685
更新日期:1982-01-01 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
doi:10.1073/pnas.0902761106
更新日期:2009-05-05 00:00:00
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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
doi:10.1073/pnas.1322170111
更新日期:2014-03-04 00:00:00
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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
doi:10.1073/pnas.0408172101
更新日期:2004-12-21 00:00:00