Boston-based private equity firm Thomas H. Lee Partners LP is buying steakhouse operator Fogo de Chao Churrascaria LLC from GP Investments for an undisclosed sum.

Privately held Fogo, founded in 1979 in Southern Brazil and now based in Dallas, has 18 restaurants in the U.S. and seven in Brazil.

J.P. Morgan and Jefferies Finance LLC are providing committed financing for the buyout.

The deal is expected to close in the third quarter, the companies said Tuesday.