Wolkenstein, Klaus

[["dc.bibliographiccitation.artnumber","e0223552"],["dc.bibliographiccitation.issue","10"],["dc.bibliographiccitation.journal","PLoS One"],["dc.bibliographiccitation.volume","14"],["dc.contributor.author","Affenzeller, Susanne"],["dc.contributor.author","Frauendorf, Holm"],["dc.contributor.author","Licha, Tobias"],["dc.contributor.author","Jackson, Daniel J."],["dc.contributor.author","Wolkenstein, Klaus"],["dc.date.accessioned","2020-08-04T08:32:28Z"],["dc.date.available","2020-08-04T08:32:28Z"],["dc.date.issued","2019"],["dc.description.abstract","Eumelanin and pheomelanin are well known and common pigments found in nature. However, their complex polymer structure and high thermostability complicate their direct chemical identification. A widely used analytical method is indirect determination using HPLC with UV detection of both types of melanin by their most abundant oxidation products: pyrrole-2,3-dicarboxylic acid (PDCA), pyrrole-2,3,5-tricarboxylic acid (PTCA), thiazole-4,5-dicarboxylic acid (TDCA), and thiazole-2,4,5-tricarboxylic acid (TTCA). An increasing interest in pigmentation in biological research led us to develop a highly sensitive and selective method to identify and quantify these melanin markers in diverse biological samples with complex matrices. By introducing solid-phase extraction (SPE, reversed-phase) following alkaline oxidation we could significantly decrease background signals while maintaining recoveries greater than 70%. Our HPLC-UV-MS method allows for confident peak identification via exact mass information in corresponding UV signals used for quantitation. In addition to synthetic melanin and Sepia officinalis ink as reference compounds eumelanin markers were detected in brown human hair and a brown bivalve shell (Mytilus edulis). Brown feathers from the common chicken (Gallus g. domesticus) yielded all four eumelanin and pheomelanin markers. The present method can be easily adapted for a wide range of future studies on biological samples with unknown melanin content."],["dc.identifier.doi","10.1371/journal.pone.0223552"],["dc.identifier.pmid","31622353"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/16606"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/67513"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1932-6203"],["dc.relation.orgunit","Abteilung Geobiologie"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.title","Quantitation of eumelanin and pheomelanin markers in diverse biological samples by HPLC-UV-MS following solid-phase extraction"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2442"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Scientific Reports"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Affenzeller, Susanne"],["dc.contributor.author","Wolkenstein, Klaus"],["dc.contributor.author","Frauendorf, Holm"],["dc.contributor.author","Jackson, Daniel J."],["dc.date.accessioned","2020-08-04T07:37:40Z"],["dc.date.available","2020-08-04T07:37:40Z"],["dc.date.issued","2020"],["dc.description.abstract","The common grove snail Cepaea nemoralis displays a stable pigmentation polymorphism in its shell that has held the attention of scientists for decades. While the details of the molecular mechanisms that generate and maintain this diversity remain elusive, it has long been employed as a model system to address questions related to ecology, population genetics and evolution. In order to contribute to the ongoing efforts to identify the genes that generate this polymorphism we have tested the long-standing assumption that melanin is the pigment that comprises the dark-brown bands. Surprisingly, using a newly established analytical chemical method, we find no evidence that eumelanin is differentially distributed within the shells of C. nemoralis. Furthermore, genes known to be responsible for melanin deposition in other metazoans are not differentially expressed within the shell-forming mantle tissue of C. nemoralis. These results have implications for the continuing search for the supergene that generates the various pigmentation morphotypes."],["dc.identifier.doi","10.1038/s41598-020-59185-y"],["dc.identifier.pmid","32051478"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/67511"],["dc.language.iso","en"],["dc.relation.issn","2045-2322"],["dc.relation.orgunit","Abteilung Geobiologie"],["dc.title","Challenging the concept that eumelanin is the polymorphic brown banded pigment in Cepaea nemoralis"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","47"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Frontiers in Zoology"],["dc.bibliographiccitation.volume","16"],["dc.contributor.author","Affenzeller, Susanne"],["dc.contributor.author","Wolkenstein, Klaus"],["dc.contributor.author","Frauendorf, Holm"],["dc.contributor.author","Jackson, Daniel J."],["dc.date.accessioned","2020-08-04T07:39:30Z"],["dc.date.available","2020-08-04T07:39:30Z"],["dc.date.issued","2019"],["dc.description.abstract","The geometric patterns that adorn the shells of many phylogenetically disparate molluscan species are comprised of pigments that span the visible spectrum. Although early chemical studies implicated melanin as a commonly employed pigment, surprisingly little evidence generated with more recent and sensitive techniques exists to support these observations."],["dc.identifier.doi","10.1186/s12983-019-0346-5"],["dc.identifier.pmid","31889966"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/17046"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/67512"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1742-9994"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0/"],["dc.title","Eumelanin and pheomelanin pigmentation in mollusc shells may be less common than expected: insights from mass spectrometry"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]