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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1981 Jan;78(1):266–269. doi: 10.1073/pnas.78.1.266

Replacement of riboflavin by an analogue in the blue-light photoreceptor of Phycomyces

M K Otto 1,*, M Jayaram 1,†, R M Hamilton 1, M Delbrück 1,‡
PMCID: PMC319033  PMID: 16592946

Abstract

Under suitable conditions, roseoflavin [7-methyl-8-dimethylamino-10-(1′-D-ribityl)isoalloxazine] replaces riboflavin to about 80% in the photoreceptor of Phycomyces. The substitute-bearing photoreceptor functions with an efficiency of about 0.1% of that of the normal receptor. The substitution is proven by (i) a decrease of the effective light flux by a factor of 4.7, expressed as a corresponding increase in threshold, and (ii) an increase of the effectiveness of 529-nm light relative to 380-nm light. It has also been shown that roseoflavin is taken up by the mycelium, translocated to the sporangiophore, and effectively phosphorylated by the riboflavin kinase of Phycomyces.

Keywords: roseoflavin, photobiology

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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