[38]Physical properties of purified calf brain tubulin

This chapter summarizes characteristic properties of calf brain tubulin, which can be used as standards in establishing the purity and integrity of tubulin preparations. While the methods described in this chapter should be applicable to pure tubulin prepared by a variety of procedures, the experience of the authors is limited to highly purified tubulin isolated by the modified Weisenberg procedure; therefore, the values of all physical parameters presented in this chapter should be regarded as valid only for this protein. The methods described in this chapter are those involved in (1) the handling of the protein for experimentation, starting with the purified tubulin stored in liquid nitrogen, (2) the routine characterization of the protein to establish its homogeneity and biochemical integrity, and (3) the determination of its other physical properties.