Iodoacetyl-LC-biotin

Iodoacetyl-LC-biotin is water-insoluble and therefore must be dissolved in an organic solvent prior to addition to an aqueous reaction medium. Suitable solvents include DMSO and DMF. Concentrated stock solutions may be prepared in DMSO and a small aliquot transferred... 

Iodoacetyl-LC-biotin has been used to localize the SH thiol of myosin by use of an avidin-biotin complex visualized by electron microscopy (Sutoh et al., 1984) and to determine the spatial relationship between SHj and the actin binding site on the myosin subfragment-1 surface (Yamamoto et al., 1984). 

Dissolve iodoacetyl-LC-biotin (Thermo Fisher) in DMF at a concentration of 4 mM (2 mg/ml). Protect from light. 

Add 50 xl of the iodoacetyl-LC-biotin solution to each milliliter of the protein solution. Mix well. This level of addition represents a 3.28-fold molar excess of biotinylation reagent over the quantity of protein present if the protein has a molecular weight of 67,000 and possesses one sulfhydryl. Adjustments to the amount of reagent addition may have to be made to be appropriate for other... 

Incubate the reaction mixture for 90 min at room temperature. If the labeling reagent is iodoacetyl-LC-biotin (Pierce), both the reagent and the reaction mixture should be protected from light. 

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