Accepted_test

The CopC (copper resistant proteins) family is periplasmic, copper-binding proteins that play an important role in copper homeostasis. CopC was initially considered as one of the components of the copper resistance system - CopABCDERS. But later it was found that CopC is often present in gene clusters only with the inner membrane protein CopD, and also genes of cuproenzymes. It is assumed that CopC in this case functions as a metallochaperone, which binds copper ions and then incorporates in the active center of cuproenzymes. In the genome of the bacterium Thiolkalivibrio paradoxus, the CopCD genes are included in the gene cluster responsible for the biosynthesis of the copper-containing thiocyanate dehydrogenase (TcDH). In this work, structures of CopC- a potential metallochaperone of TcDH - were obtained , and structural changes in apo- and holo-forms were identified.