Digitization of sedimentation equilibrium and velocity data for analysis by minicomputer

✍ Scribed by Thomas F. Holzman; Steven P. Leytus; Thomas O. Baldwin; Walter F. Mangel

• Book ID: 102985928
• Publisher: Elsevier Science
• Year: 1982
• Tongue: English
• Weight: 889 KB
• Volume: 119
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(82)90665-0

✦ Synopsis

A fast, efficient, and accurate method to obtain solute sedimentation coefficients and molecular weights from analytical ultracentrifugation data is described. Recorder tracings from the photoelectric scanner of a Beckman Model E analytical ultracentrifuge are analyzed with a computer program after being entered into a minicomputer via a digitizer board. The method is a simple, low-cost, and resource-efficient alternative to complex methods of modifying the ultracentrifuge for similar purposes. Even nonideal and polydisperse solute samples may be analyzed. To illustrate this method sedimentation equilibrium data for a mutant bacterial luciferase, AK-6, are analyzed. Two major species are detected, the dimeric enzyme with an apparent mass average molecular weight, Mw,,,, of 71,000 and dissociated subunits with an I);iv.aw of 40,000. This method is used to calculate the sedimentation coefficients of native and proteolyzed samples of bacterial luciferase from three species of luminous marine bacteria (Holzman, T. F., and Baldwin, T. 0. (1980) Proc. Nat. Acad. Sci. USA 77, 6363-6367).