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. 1978 Mar;21(3):195–202. doi: 10.1016/S0006-3495(78)85519-2

Quantum yield and image contrast of bacteriochlorophyll monolayers in photoelectron microscopy.

R B Barnes, J Amend, W R Sistrom, O H Griffith
PMCID: PMC1473685  PMID: 630040

Abstract

The photoelectron quantum yield spectrum of bacteriochlorophyll aGg (Bchl a ) from Rhodospirillum rubrum was determined in order to evaluate the possibility of mapping photoreceptor distribution and organization in bacterial chromatophores. The quantum yield is on the order of 1 X 10(-3) electrons/incident photon at 180 nm and decreases to 2.5 X 10(-5) electrons/incident photon at 230 nm. Photoelectron micrographs confirm the high contrast predicted between monolayers of Bchl a against a lipid background (calcium arachidate). A significant contrast difference is found between the two monolayer orientations, demonstrating that photoelectron microscopy is a sensitive detector of asymmetry in Bch1 a monolayers.

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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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