Streptolysin O: Sedimentation Coefficient and Molecular Weight Determinations

Streptolysin O: sedimentation coefficient and molecular weight determinations.

The sedimentation coefficient of streptolysin O as determined by sucrose density gradient ultracentrifugation is 3.7S. An approximate molecular weight of 60,500 was calculated from the sedimentation velocity, and a similar value was obtained by Sephadex gel filtration. There was no measurable difference in the sedimentation coefficient of streptolysin O in either the active or reversibly inacti...

Polymolecularity and Polydispersity in Molecular Weight Determinations

The influence of polymolecularity on molecular weight determinations is reviewed. Several molecular weight methods give so-called mixed averages, i.e. averages which are based on more than one moment of the molecular weight distribution or on powers of the moment. Molecular weight averages can be subdivided into simple, exponential resolved, order resolved and power resolved averages. Mixed ave...

Molecular weight determinations of soluble and membrane-bound fractions of choline O-acetyltransferase in rat brain.

Three fractions of choline O-acetyltransferase (ChAT) (EC 2.3.1.6) were solubilized from a nerve ending fraction of rat forebrain using three sequential washes of an increasingly chaotrophic nature (100 mM sodium phosphate, pH 7.4; 500 mM NaCl; 2% Triton DN-65) as previously described (Benishin, C.G., and P.T. Carroll (1983) J. Neurochem. 41: 1030-1039). The molecular weights of the soluble (Na...

Sedimentation, diffusion, and molecular weight of crystalline pituitary growth hormone.

The recent work of Fishman, Wilhelmi, and Russell (1,2) has made available a crystalline growth hormone isolated from the bovine anterior pituitary gland. It was of considerable interest to determine the sedimentation behavior of this protein in the ultracentrifuge and, at the same time, to obtain the molecular weight by this method. The amorphous preparation of Li, Evans, and Simpson (3) has n...

Sedimentation and diffusion studies on insulin: the maximum molecular weight.