New method for identifying genetic variants of human proalbumin
Rochu, D.; Fine, J.M.
Clinical Chemistry 32(11): 2063-2065
1986
ISSN/ISBN: 0009-9147 PMID: 2430733 Document Number: 283627
We describe a simple, rapid procedure for identifying the proalbumin nature of certain genetic variants of human albumin. Because both albumin and its precursor, proalbumin, exhibit multiple binding sites for Cu(II), we investigated the conditions for selective linkage of metal ions to the high-affinity N-terminal binding site of albumin. Guided by these data, we then developed a sensitive color test for detection of Cu(II)-albumin complexes after cellulose acetate electrophoresis of serum samples previously incubated with Cu(II). Use of dithiooxamide in ethanol-acetic acid solution allows protein fixation and copper staining in a single step. The simplicity of the procedure, together with the use of nonradioactive metal ions, makes it very useful for rapidly identifying proalbumin variants.