Melanin biosynthesis by Frankia strain CeI5
(2007) In Physiologia Plantarum 131(2). p.90-180- Abstract
Many Frankia strains are pigmented and presumed to produce melanin. However, melanin biosynthesis has yet to be rigorously characterized in Frankia. This study was initiated to determine whether or not Frankia strain CeI5 produced melanin and to identify the biochemical pathway of pigment production. Frankia strain CeI5 first produced a dark pigment in mycelial and other tissue and then in the liquid culture medium when grown in a defined medium containing l-tyrosine. The pigment resisted solvents, lightened when subjected to the action of oxidants, as well as reductants, and produced a flocculent brown precipitate with FeCl(3). Spectroscopic characteristics of the extracted pigment were those of melanin. When subjected to gradual... (More)
Many Frankia strains are pigmented and presumed to produce melanin. However, melanin biosynthesis has yet to be rigorously characterized in Frankia. This study was initiated to determine whether or not Frankia strain CeI5 produced melanin and to identify the biochemical pathway of pigment production. Frankia strain CeI5 first produced a dark pigment in mycelial and other tissue and then in the liquid culture medium when grown in a defined medium containing l-tyrosine. The pigment resisted solvents, lightened when subjected to the action of oxidants, as well as reductants, and produced a flocculent brown precipitate with FeCl(3). Spectroscopic characteristics of the extracted pigment were those of melanin. When subjected to gradual dilution, the absorbance decreased unevenly, occurring in the near red range first, then in the visible range, and lastly in the UV range. This observation might resolve the question of why quite different descriptions of melanin UV-visible light absorption spectra exist in the literature. The tyrosinase cofactor copper greatly enhanced melanin biosynthesis at 5.3 x 10(-6) M, while 1 x 10(-8) M 3,4-dihydroxy-l-phenylalanine hastened pigmentation. The copper-chelating agent KCN and the tyrosinase inhibitor tropolone decreased melanin production at the same concentration of 1 x 10(-5) M. This evidence suggests that Frankia strain CeI5 produces melanin via the Raper and Mason pathway.
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- author
- Yuan, Wenlin ; Burleigh, Stephen H LU and Dawson, Jeffrey O
- publishing date
- 2007-10
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Copper/metabolism, Frankia/drug effects, Levodopa/pharmacology, Melanins/analysis, Monophenol Monooxygenase/metabolism, Potassium Cyanide/pharmacology, Spectrophotometry/methods, Tropolone/pharmacology
- in
- Physiologia Plantarum
- volume
- 131
- issue
- 2
- pages
- 90 - 180
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- scopus:34548463492
- pmid:18251890
- ISSN
- 0031-9317
- DOI
- 10.1111/j.1399-3054.2007.00948.x
- language
- English
- LU publication?
- no
- id
- d5ea3db7-71ba-419b-864c-0744317d2bf9
- date added to LUP
- 2018-10-17 15:40:46
- date last changed
- 2024-01-15 04:25:07
@article{d5ea3db7-71ba-419b-864c-0744317d2bf9,
abstract = {{<p>Many Frankia strains are pigmented and presumed to produce melanin. However, melanin biosynthesis has yet to be rigorously characterized in Frankia. This study was initiated to determine whether or not Frankia strain CeI5 produced melanin and to identify the biochemical pathway of pigment production. Frankia strain CeI5 first produced a dark pigment in mycelial and other tissue and then in the liquid culture medium when grown in a defined medium containing l-tyrosine. The pigment resisted solvents, lightened when subjected to the action of oxidants, as well as reductants, and produced a flocculent brown precipitate with FeCl(3). Spectroscopic characteristics of the extracted pigment were those of melanin. When subjected to gradual dilution, the absorbance decreased unevenly, occurring in the near red range first, then in the visible range, and lastly in the UV range. This observation might resolve the question of why quite different descriptions of melanin UV-visible light absorption spectra exist in the literature. The tyrosinase cofactor copper greatly enhanced melanin biosynthesis at 5.3 x 10(-6) M, while 1 x 10(-8) M 3,4-dihydroxy-l-phenylalanine hastened pigmentation. The copper-chelating agent KCN and the tyrosinase inhibitor tropolone decreased melanin production at the same concentration of 1 x 10(-5) M. This evidence suggests that Frankia strain CeI5 produces melanin via the Raper and Mason pathway.</p>}},
author = {{Yuan, Wenlin and Burleigh, Stephen H and Dawson, Jeffrey O}},
issn = {{0031-9317}},
keywords = {{Copper/metabolism; Frankia/drug effects; Levodopa/pharmacology; Melanins/analysis; Monophenol Monooxygenase/metabolism; Potassium Cyanide/pharmacology; Spectrophotometry/methods; Tropolone/pharmacology}},
language = {{eng}},
number = {{2}},
pages = {{90--180}},
publisher = {{John Wiley & Sons Inc.}},
series = {{Physiologia Plantarum}},
title = {{Melanin biosynthesis by Frankia strain CeI5}},
url = {{http://dx.doi.org/10.1111/j.1399-3054.2007.00948.x}},
doi = {{10.1111/j.1399-3054.2007.00948.x}},
volume = {{131}},
year = {{2007}},
}