Utilization of protein splicing for purification of the human growth hormone

Developing simple and reliable methods to purify recombinant proteins is among the most important problems of modern biotechnology. It is of particular interest to take advantage of protein splicing for this purpose. Affinity tagging of inteins allows the use of regular protocols for protein purification. Autocatalytic excision of the tagged intein yields the pure protein lacking N-terminal formylmethionine. A new purification technique was developed on the basis of protein splicing for the human growth hormone. The Mxe GyrA intein with the histidine tag or cellulose-binding domain was used as a self-removable affinity unit. The resulting two-step purification protocol makes it possible to obtain the human growth hormone having the native N terminus with minimal losses.