Abstract：
:Amide linkages are among the most important chemical bonds in living systems, constituting the connections between amino acids in peptides and proteins. We demonstrate the controlled formation of amide bonds between amino acids or peptides in the gas phase using ion/ion reactions in a mass spectrometer. Individual amino acids or peptides can be prepared as reagents by (i) incorporating gas phase-labile protecting groups to silence otherwise reactive functional groups, such as the N terminus; (ii) converting the carboxyl groups to the active ester of N-hydroxysuccinimide; and (iii) incorporating a charge site. Protonation renders basic sites (nucleophiles) unreactive toward the N-hydroxysuccinimide ester reagents, resulting in sites with the greatest gas phase basicities being, in large part, unreactive. The N-terminal amines of most naturally occurring amino acids have lower gas phase basicities than the side chains of the basic amino acids (i.e., those of histidine, lysine, or arginine). Therefore, reagents may be directed to the N terminus of an existing "anchor" peptide to form an amide bond by protonating the anchor peptide's basic residues, while leaving the N-terminal amine unprotonated and therefore reactive. Reaction efficiencies of greater than 30% have been observed. We propose this method as a step toward the controlled synthesis of peptides in the gas phase.
journal_name
Proc Natl Acad Sci U S Aauthors
McGee WM,McLuckey SAdoi
10.1073/pnas.1317914111subject
Has Abstractpub_date
2014-01-28 00:00:00pages
1288-92issue
4eissn
0027-8424issn
1091-6490pii
1317914111journal_volume
111pub_type
杂志文章abstract：:Complement receptors (CRs), expressed notably on myeloid and lymphoid cells, play an essential function in the elimination of complement-opsonized pathogens and apoptotic/necrotic cells. In addition, these receptors are crucial for the cross-talk between the innate and adaptive branches of the immune system. CR3 (also...
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.1311261110
更新日期：2013-10-08 00:00:00
abstract：:8-L-Arginine vasopressin ([Arg8]VP) receptors are expressed transiently in the rat facial nucleus during the perinatal period. Electrophysiological studies suggest that at least part of these receptors is located on facial motoneurones. In the present study we report that, in the adult rat, unilateral section of a fac...
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.91.20.9636
更新日期：1994-09-27 00:00:00
abstract：:Pathway proteomics strategies measure protein expression changes in specific cellular processes that carry out related functions. Using targeted tandem mass tags-based sample multiplexing, hundreds of proteins can be quantified across 10 or more samples simultaneously. To facilitate these highly complex experiments, w...
journal_title：Proceedings of the National Academy of Sciences of the United States of America
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doi：10.1073/pnas.1919410117
更新日期：2020-05-05 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.1315121111
更新日期：2014-02-04 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.94.11.5611
更新日期：1997-05-27 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.93.19.10222
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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.91.4.1248
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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.76.4.1896
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更新日期：2014-02-18 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.79.24.7609
更新日期：1982-12-01 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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更新日期：1975-09-01 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.76.1.373
更新日期：1979-01-01 00:00:00
abstract：:Although it is accepted that regulatory T cells (T regs) contribute to cancer progression, most studies in the field consider nonantigen-specific suppression. Here, we show the presence of tumor antigen-specific CD4(+) T regs in the blood of patients with metastatic melanoma. These CD4(+) T regs recognize a broad rang...
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.0710557105
更新日期：2007-12-26 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.70.7.2033
更新日期：1973-07-01 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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doi：10.1073/pnas.1518509113
更新日期：2016-04-05 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：2010-03-23 00:00:00
abstract：:The conserved Ndc80 complex is an essential microtubule-binding component of the kinetochore. Recent findings suggest that the Ndc80 complex influences microtubule dynamics at kinetochores in vivo. However, it was unclear if the Ndc80 complex mediates these effects directly, or by affecting other factors localized at ...
journal_title：Proceedings of the National Academy of Sciences of the United States of America
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更新日期：2012-10-02 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：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：1969-10-01 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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更新日期：2018-10-02 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：1990-02-01 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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更新日期：2019-05-28 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：2020-09-29 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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更新日期：2009-08-25 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：1986-10-01 00:00:00
abstract：:Prostaglandin E1 and the beta-adrenergic hormone l-isoproterenol stimulated cyclic AMP formation in both nucleated and enucleated myeloid leukemic cells that could be induced to differentiate normally to mature cells by the macrophage- and granulocyte-inducing protein MGI (MGI+D+ cells). Enucleated as well as nucleate...
journal_title：Proceedings of the National Academy of Sciences of the United States of America
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doi：10.1073/pnas.77.8.4798
更新日期：1980-08-01 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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更新日期：2019-08-13 00:00:00
abstract：:Recent advances in cell-free expression protocols have opened a new avenue toward high-resolution structural investigations of membrane proteins by x-ray crystallography and NMR spectroscopy. One of the biggest challenges for liquid-state NMR-based structural investigations of membrane proteins is the significant peak...
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.0710843105
更新日期：2008-06-17 00:00:00
