May be used for the removal of DNA from protein samples or for the purification of DNA binding proteins. It may be used as an alternative to polybrene in retroviral-mediated gene transfer.
Biochem/physiol Actions
Protamine in the form of solid lipid nanoparticles (SLN) promoted transfection with plasmid DNA more efficiently and with less cytotoxicity than comparable SLNs composed of Esterquat-1.
Purification Methods
Protamine sulfate is a strongly basic protein (white powder, see pK) used to precipitate nucleic acids from crude protein extracts. It dissolves to the extent of 1.25% in H2O. It is freely soluble in hot H2O but separates as an oil on cooling. It has been purified by chromatography on an IRA-400 ion-exchange resin in the SO 4 form and is washed with dilute H2SO4. Eluates are freeze-dried under high vacuum below 20o. This method is used to convert proteamine and protamine hydrochloride to the sulfate. [UV: Rasmussen Hoppe Seyler's Z Physiol Chem 224 97 1934, Ando & Sawada J Biochem (Tokyo) 49 252 1961, Felix & Hashimoto Hoppe Seyler's Z Physiol Chem 330 205 1963.]
