Boston--State Street Corp. will purchase Winston-Salem, N.C.-based Wachovia Bank's institutional trust and custody businesses. Wachovia's institutional businesses represent approximately 270 clients and $61 billion in assets under management. State Street will offer jobs to Wachovia's 43 institutional marketing and sales execs and staffers. To augment the acquisition, State Street, which has $5.3 trillion in assets under custody and $574 billion in assets under management, will open marketing offices in Winston-Salem and Atlanta. Wachovia is the 16th largest bank in the U.S.