Single-particle visualization of assembly: I. Dimerization in a planar zone.
Summary Single-particle fluorescence microscopy of association/dissociation is required for analysis of biological assembly reactions. Toward achieving this goal, Wang et al. (J. Microsc., 2004, 213, 101-109) used molten agarose to concentrate thermally diffusing particles in a thin zone of solution next to the surface of a coverglass (plane of concentration). The present study details the first real-time, single-particle analysis of the association/dissociation of thermally diffusing particles in the plane of concentration. The test particles were procapsids of bacteriophage lambda (radius = 31 nm). Quantification of thermal motion was developed and used to determine whether co-diffusing particles were bound to each other. The data are explained by (1) the presence of a molten agarose-generated barrier that is 93-155 nm from the coverglass surface, and (2) non-random orientation of procapsid dimers in the plane of concentration.
Wang
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Department of Biochemistry, The University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA.
Wu
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Yang
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Catalano
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Serwer
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D019281:Dimerization; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008856:Microscopy, Fluorescence; D014764:Viral Proteins / Q000737:chemistry*
D014764:Viral Proteins