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.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Barnes RB,Amend J,Sistrom WR,Griffith OHdoi
10.1016/S0006-3495(78)85519-2subject
Has Abstractpub_date
1978-03-01 00:00:00pages
195-202issue
3eissn
0006-3495issn
1542-0086pii
S0006-3495(78)85519-2journal_volume
21pub_type
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