Chemical characterization of eumelanins with special emphasis on 5,6-dihydroxyindole-2-carboxylic acid content and molecular size

Analytical Biochemistry
H OzekiI Ishiguro

Abstract

Mammalian melanins exist in two chemically distinct forms; the brown to black eumelanins and the yellow to reddish pheomelanins. Eumelanins are derived from copolymerization of 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA). Eumelanins can be quantified by HPLC analysis of the oxidation product pyrrole-2,3,5-tricarboxylic acid (PTCA) and by our spectrophotometric method (Sp.EM). We also developed a spectrophotometric method for assaying the total amount of eu- and pheomelanins by dissolving them in Soluene-350 (TM). In addition, we previously showed that Sp.EM/TM and PTCA/TM ratios are significant parameters in characterizing eumelanins produced in follicular melanocytes. The objectives of this study were (1) to clarify the significance of Sp.EM/TM and PTCA/TM ratios in synthetic eumelanins and (2) to apply these methods to characterizing natural eumelanins with various DHI/ DHICA ratios and molecular sizes. The results obtained show that (1) the Sp.EM/TM ratio of synthetic eumelanins increases as polymerization proceeds, (2) the Sp.EM/TM and PTCA/TM ratios in copolymers of DHI and DHICA correlate to the percentage content of DHICA-derived units, and (3) combination of the Sp.EM/TM and PTCA/TM ratio...Continue Reading

References

Sep 1, 1992·The Biochemical Journal·K TsukamotoG Prota
Jan 1, 1988·Pigment Cell Research·J R JaraJ A Lozano
Aug 6, 1986·Biochimica Et Biophysica Acta·S Ito
Sep 1, 1995·The Journal of Investigative Dermatology·H OzekiT Hirobe
Jan 1, 1994·Annual Review of Genetics·I J Jackson
Dec 1, 1993·Analytical Biochemistry·S ItoH Ozeki
Aug 1, 1993·Pigment Cell Research·K UrabeV J Hearing
Feb 15, 1996·European Journal of Biochemistry·A K ChakrabortyJ M Pawelek
Apr 1, 1996·Pigment Cell Research·H OzekiK Wakamatsu

❮ Previous
Next ❯

Citations

Jun 22, 2007·The Journal of Physical Chemistry. B·Lian Hong, John D Simon
May 4, 2005·Ophthalmic Research·Rangaprasad Sarangarajan, Shireesh P Apte
May 25, 2002·Pigment Cell Research·Kazumasa Wakamatsu, Shosuke Ito
May 1, 2004·Analytical Sciences : the International Journal of the Japan Society for Analytical Chemistry·Junwei Di, Shuping Bi
Jul 15, 2004·Pigment Cell Research·Marina ZoccolaRoberto Zanetti
Jan 15, 2005·Pigment Cell Research·Yan Liu, John D Simon
May 14, 2004·Pigment Cell Research·Yan LiuJohn D Simon
May 20, 2003·Pigment Cell Research·Shosuke Ito, UNKNOWN IFPCS
May 23, 2007·Pigment Cell Research·Kazumasa WakamatsuShosuke Ito
Aug 24, 2010·Pigment Cell & Melanoma Research·Shosuke Ito, Kazumasa Wakamatsu
Jul 13, 2013·Pigment Cell & Melanoma Research·Shosuke ItoKazumasa Wakamatsu
Dec 2, 2009·Photochemistry and Photobiology·Dana N Peles, John D Simon
Aug 8, 2009·Pigment Cell & Melanoma Research·Ingo BraaschManfred Schartl
Aug 16, 2000·Experimental Cell Research·V M ViradorV J Hearing
May 1, 2001·The Journal of Small Animal Practice·S YuJ G Morris
May 9, 2018·Pigment Cell & Melanoma Research·Ismael GalvánKazumasa Wakamatsu
Oct 27, 2004·Photochemistry and Photobiology·Yan LiuJohn D Simon
Mar 21, 2008·Pigment Cell & Melanoma Research·Kazumasa WakamatsuShosuke Ito
Jan 25, 2006·Melanoma Research·Rangaprasad Sarangarajan, Shireesh P Apte
Sep 21, 2006·The Journal of Biological Chemistry·Dana N MosesJ Herbert Waite
Feb 10, 2021·Journal of the American Chemical Society·Wei CaoNathan C Gianneschi
Sep 27, 2008·The Journal of Physical Chemistry. B·John D SimonDana N Peles
Nov 21, 2000·The International Journal of Biochemistry & Cell Biology·K J Rodgers, R T Dean
May 9, 2003·Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy·Junwei Di, Shuping Bi
Mar 7, 2003·Fungal Genetics and Biology : FG & B·Kim LangfelderAxel A Brakhage
Oct 30, 2003·Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy·Junwei Di, Shuping Bi

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.