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Study · Not a test of the peptide alone · 2005

3 results

Acid-base titration of melanocortin peptides: evidence of Trp rotational conformers interconversion.

Fernandez RM, Vieira RF, Nakaie CR, Lamy MT, Ito AS

Biopolymers1 Jan 2005Cited by 7 (Europe PMC)

PMID15657882 (opens in a new tab)DOI10.1002/bip.20210 (opens in a new tab)PepBankPUB-15657882
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Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study3

No result from this study comes from a test of the peptide.

Studies that did not test the peptide alone3

In this study, Melanotan I (afamelanotide) was a lab tool or a carrier, part of a mix, or the subject of a lab method. These results are not evidence about taking Melanotan I (afamelanotide).

  1. 01LabNot a test of Melanotan I (afamelanotide) aloneIn vitro (cell-free)Other

    Global analysis of fluorescence decay profiles showed that, for each peptide including NDP-MSH, the data fitted three lifetimes whose values remained constant.

    In plain wordsIn lab tests, the fluorescence of NDP-MSH fitted three constant lifetimes across the pH range.

    Peptide
    Melanotan I (afamelanotide)
    Outcome
    Not applicableTryptophan fluorescence lifetimes across pH
    Study

    n: not reported in source

    Outcome group
    Peptide structure and chemistry · Pharmacology

    Source sentences

    Summary
    Global analysis of fluorescence decay profiles measured in the pH range between 2.0 and 11.0 showed that, for each peptide, the data could be well fitted to three lifetimes whose values remained constant.
    1 context sentence
    Summary · context
    Tryptophantime-resolved fluorescence was used to monitor acid-base titration properties of alpha-melanocyte stimulating hormone (alpha-MSH) and the biologically more potent analog [Nle4, D-Phe7]alpha -MSH (NDP-MSH), labeled or not with the paramagnetic amino acid probe 2,2,6,6-tetramthylpiperidine-N…

    In this study, Melanotan I (afamelanotide) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Melanotan I (afamelanotide).

  2. 02LabNot a test of Melanotan I (afamelanotide) aloneIn vitro (cell-free)Other

    The long and intermediate lifetime factors interconverted along the pH interval, interpreted as interconversion between Trp rotamers driven by changes in side-chain ionization.

    In plain wordsIn lab tests, the shape of the peptide's tryptophan group shifted between forms as the acidity changed.

    Peptide
    Melanotan I (afamelanotide)
    Outcome
    Not applicableTrp rotamer interconversion with pH
    Study

    n: not reported in source

    Outcome group
    Peptide structure and chemistry · Pharmacology

    Source sentences

    Summary
    The long and intermediate lifetime preexponential factors interconverted along that pH interval and the result was interpreted as due to interconversion between Trp g- and trans chi1 rotamers, driven by conformational changes promoted by modifications in the ionization state of side-chain residues.
    1 context sentence
    Summary · context
    Tryptophantime-resolved fluorescence was used to monitor acid-base titration properties of alpha-melanocyte stimulating hormone (alpha-MSH) and the biologically more potent analog [Nle4, D-Phe7]alpha -MSH (NDP-MSH), labeled or not with the paramagnetic amino acid probe 2,2,6,6-tetramthylpiperidine-N…

    In this study, Melanotan I (afamelanotide) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Melanotan I (afamelanotide).

  3. 03LabNot a test of Melanotan I (afamelanotide) aloneIn vitro (cell-free)Other

    The extent of rotamer interconversion differed between alpha-MSH and NDP-MSH, indicating structural differences between the peptides.

    In plain wordsIn lab tests, alpha-MSH and NDP-MSH differed in structure.

    Peptide
    Melanotan I (afamelanotide)
    Outcome
    Not applicableStructural difference between alpha-MSH and NDP-MSH
    Study

    n: not reported in source

    Outcome group
    Peptide structure and chemistry · Pharmacology

    Source sentences

    Summary
    The differences in the extent of interconversion in alpha-MSH and NDP-MSH are indicative of structural differences between the peptides, while titration curves suggest structural similarities between each peptide and its Toac-labeled species, in aqueous solution.

    In this study, Melanotan I (afamelanotide) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Melanotan I (afamelanotide).

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

  1. Version 2Current

    13 Oct 2026, 21:44 UTC

    Study results updated

  2. Version 1

    13 Oct 2026, 16:31 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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