Wall Street stalwart Wachtell, Lipton, Rosen & Katz took the lead Wednesday advising BB&T Corp. on its $2.5 billion cash-and-stock purchase of Susquehanna Bancshares, having recently handled two other banking consolidation deals for clients AmericanWest Bank and Sterling Bancorp.

The purchase of Lititz, Pa.-based Susquehanna by BB&T, which earlier this year was the nation’s 12th-largest bank by deposits before a spate of acquisitions, will help the latter expand into the mid-Atlantic region. Winston-Salem, N.C.-based BB&T turned to Wachtell in September to handle its purchase of 41 Citibank branches in Texas and $363 million cash-and-stock buy of the Bank of Kentucky. Not surprisingly, Wachtell also got the call for BB&T’s Susquehanna buy.