Chlorophyll-sensitized oxidation-reduction reactions of hemin in pyridine

M. Brody, Suse Broyde, C. C. Yeh, S. S. Brody

Research output: Contribution to journalArticle

Abstract

In one of the photochemical reaction systems of photosynthesis (system I), the primary process is believed to involve an electron transfer between cytochrome and chlorophyll. As an in vitro model for this system, a study has been made of the photochemical reactions between chlorophyll a and hemin, in pyridine solution. A slow dark reduction, undergone by hemin in pyridine, is accelerated by the presence of chlorophyll, and both red and green light further increase the rate of the reaction. A mechanism proposed for this reaction is electron transfer from chlorophyll to hemin, with recovery of oxidized chlorophyll at the expense of solvent. Chlorophyll also sensitizes the photooxidation of reduced hemin in air. The kinetics of this reaction are similar to those of other sensitized photooxidations, indicating a similar mechanism. Quenching of chlorophyll fluorescence by low concentrations of hemin or reduced hemin suggest the existence of a complex between chlorophyll and hemin.

Original languageEnglish (US)
Pages (from-to)3007-3015
Number of pages9
JournalBiochemistry
Volume7
Issue number8
StatePublished - 1968

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Hemin
Redox reactions
Chlorophyll
Oxidation-Reduction
Photooxidation
Photochemical reactions
Electrons
Methyl Green
Photosynthesis
Cytochromes
pyridine
Quenching
Fluorescence
Air
Recovery
Kinetics

ASJC Scopus subject areas

  • Biochemistry

Cite this

Brody, M., Broyde, S., Yeh, C. C., & Brody, S. S. (1968). Chlorophyll-sensitized oxidation-reduction reactions of hemin in pyridine. Biochemistry, 7(8), 3007-3015.

Chlorophyll-sensitized oxidation-reduction reactions of hemin in pyridine. / Brody, M.; Broyde, Suse; Yeh, C. C.; Brody, S. S.

In: Biochemistry, Vol. 7, No. 8, 1968, p. 3007-3015.

Research output: Contribution to journalArticle

Brody, M, Broyde, S, Yeh, CC & Brody, SS 1968, 'Chlorophyll-sensitized oxidation-reduction reactions of hemin in pyridine', Biochemistry, vol. 7, no. 8, pp. 3007-3015.
Brody, M. ; Broyde, Suse ; Yeh, C. C. ; Brody, S. S. / Chlorophyll-sensitized oxidation-reduction reactions of hemin in pyridine. In: Biochemistry. 1968 ; Vol. 7, No. 8. pp. 3007-3015.
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