AFFINITY BINDING OF DISTINCT FUNCTIONAL FIBRONECTIN DOMAINS TO IMMOBILIZED METAL-CHELATES

Fibronectin has been found to bind metal ions. Using metal chelate chr omatography and limited proteolysis to generate the distinct functiona l domains of fibronectin we set out to address the metal binding sites to well-defined regions of fibronectin. The results show that the aff inity binding of fibronectin to Co2+ is mediated exclusively via the c ollagen binding domain of the molecule, whereas fibronectin will bind to Zn2+, Ni2+, and Cu2+ by metal binding sites located in two, three, and four well-defined regions of fibronectin, respectively, Fe2+ and M n2+ chelates did not bind any of the isolated fibronectin domains. Com bined metal chelate affinity chromatography opens a possibility to iso late particular fibronectin domains. (C) 1995 Academic Academic Press, Inc.