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The influence of iron on selected properties of synthetic pheomelanin
It is believed that while eumelanin plays photoprotective and antioxidant role in pigmented tissues, pheomelanin being more photoreactive could behave as a phototoxic agent. Although the metal ion-sequestering ability of melanin might be protective, transition metal ions present in natural melanins...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Springer US
2020
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7266848/ https://www.ncbi.nlm.nih.gov/pubmed/32451722 http://dx.doi.org/10.1007/s12013-020-00918-1 |
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author | Zadlo, Andrzej Mokrzyński, Krystian Ito, Shosuke Wakamatsu, Kazumasa Sarna, Tadeusz |
author_facet | Zadlo, Andrzej Mokrzyński, Krystian Ito, Shosuke Wakamatsu, Kazumasa Sarna, Tadeusz |
author_sort | Zadlo, Andrzej |
collection | PubMed |
description | It is believed that while eumelanin plays photoprotective and antioxidant role in pigmented tissues, pheomelanin being more photoreactive could behave as a phototoxic agent. Although the metal ion-sequestering ability of melanin might be protective, transition metal ions present in natural melanins could affect their physicochemical properties. The aim of this research was to study iron binding by pheomelanin and analyze how such a binding affects selected properties of the melanin. Synthetic pheomelanin (CDM), prepared by enzymatic oxidation of DOPA in the presence of cysteine was analyzed by electron paramagnetic resonance (EPR) spectroscopy, spectrophotometry, chemical analysis, and time-resolved measurements of singlet oxygen phosphorescence. Iron broadened EPR signal of melanin and increased its optical absorption. Iron bound to melanin exhibited EPR signal at g = 4.3, typical for high-spin iron (III). Iron bound to melanin significantly altered the kinetics of melanin photodegradation, which in turn modified the accessibility and stability of the melanin–iron complexes as indicated by the release of iron from melanin induced by diethylenetriaminepentaacetic acid and KCN. Although bound to melanin iron little affects initial stages of photodegradation of CDM, the effect of iron becomes more pronounced at later stages of melanin photolysis. |
format | Online Article Text |
id | pubmed-7266848 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | Springer US |
record_format | MEDLINE/PubMed |
spelling | pubmed-72668482020-06-15 The influence of iron on selected properties of synthetic pheomelanin Zadlo, Andrzej Mokrzyński, Krystian Ito, Shosuke Wakamatsu, Kazumasa Sarna, Tadeusz Cell Biochem Biophys Original Paper It is believed that while eumelanin plays photoprotective and antioxidant role in pigmented tissues, pheomelanin being more photoreactive could behave as a phototoxic agent. Although the metal ion-sequestering ability of melanin might be protective, transition metal ions present in natural melanins could affect their physicochemical properties. The aim of this research was to study iron binding by pheomelanin and analyze how such a binding affects selected properties of the melanin. Synthetic pheomelanin (CDM), prepared by enzymatic oxidation of DOPA in the presence of cysteine was analyzed by electron paramagnetic resonance (EPR) spectroscopy, spectrophotometry, chemical analysis, and time-resolved measurements of singlet oxygen phosphorescence. Iron broadened EPR signal of melanin and increased its optical absorption. Iron bound to melanin exhibited EPR signal at g = 4.3, typical for high-spin iron (III). Iron bound to melanin significantly altered the kinetics of melanin photodegradation, which in turn modified the accessibility and stability of the melanin–iron complexes as indicated by the release of iron from melanin induced by diethylenetriaminepentaacetic acid and KCN. Although bound to melanin iron little affects initial stages of photodegradation of CDM, the effect of iron becomes more pronounced at later stages of melanin photolysis. Springer US 2020-05-24 2020 /pmc/articles/PMC7266848/ /pubmed/32451722 http://dx.doi.org/10.1007/s12013-020-00918-1 Text en © The Author(s) 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. |
spellingShingle | Original Paper Zadlo, Andrzej Mokrzyński, Krystian Ito, Shosuke Wakamatsu, Kazumasa Sarna, Tadeusz The influence of iron on selected properties of synthetic pheomelanin |
title | The influence of iron on selected properties of synthetic pheomelanin |
title_full | The influence of iron on selected properties of synthetic pheomelanin |
title_fullStr | The influence of iron on selected properties of synthetic pheomelanin |
title_full_unstemmed | The influence of iron on selected properties of synthetic pheomelanin |
title_short | The influence of iron on selected properties of synthetic pheomelanin |
title_sort | influence of iron on selected properties of synthetic pheomelanin |
topic | Original Paper |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7266848/ https://www.ncbi.nlm.nih.gov/pubmed/32451722 http://dx.doi.org/10.1007/s12013-020-00918-1 |
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