UPDATE 2-Former Brazil central bank head to join KKR

* Henrique Meirelles starts as senior adviser immediately

* Formal central banker oversaw Brazil's recent boom

* Meirelles collects board posts at Lazard, J&F, Azul

June 18 (Reuters) - Private equity firm KKR & Co LP appointed Henrique Meirelles as a senior adviser on Monday, giving the longest-serving central bank president in Brazilian history his latest high profile job in a string of private-sector leadership roles.

Meirelles headed Brazil's central bank from 2003 to 2010, helping to burnish the country's inflation-fighting credentials and steer the Brazilian economy through its biggest boom in almost three decades.

Since leaving the bank in December, Meirelles has accumulated board positions and advisory work.

He is currently chairman of both the Lazard Americas unit of investment bank Lazard Ltd and Brazilian holding company J&F Participações, which controls the world's biggest meat packer, JBS, and other agricultural powerhouses.

Meirelles also serves on the board of Azul Linhas Aereas, the Brazilian airline started by JetBlue Airways founder David Neeleman. Brazil's President Dilma Rousseff appointed him last year to manage an agency coordinating investments for the 2016 Olympics in Rio de Janeiro.

The former central banker originally came from the private sector, where he was president of Corporate and Global Banking for FleetBoston from 2000 to October 2001. He had previously been president and COO of BankBoston from 1996 to 1999.

Meirelles, whose appointment is effective immediately, will play an important role in KKR's activities in Brazil and Latin America, the company said in a statement.

KKR appointed former Morgan Stanley chief executive John Mack to its senior advisory team in March.