查看文章

Department of Biochemistry, State University of New York at Stony Brook, Stony Brook, New York 11794-5215 Received June 20, 1986; Revised Manuscript Received September 23, 1986 abstract: This report describes a method suitable for determining the depth of a wide variety of fluorescent molecules embedded in membranes. The method involves determination of the parallax in the apparent location of fluorophores detected when quenching by phospholipids spin-labeledat two different depths is compared. By use of straightforward algebraic expressions, the method allows calculation of depth in angstroms. Furthermore, the analysis can be extended toquenching by energy-transfer acceptors or bro-minated probes under appropriate conditions. Application of the methodto quenching of 7-nitro-2, l, 3-benzoxadiazol-4-yl (NBD)-labeled lipids by spin-labeled lipids located at three different depths is demonstrated …