(Bloomberg News) Sallie Krawcheck, president of Bank of America Corp.'s wealth-management division, picked John Thiel to replace Lyle LaMothe as head of the firm's Merrill Lynch brokerage, according to a memo.

Thiel, who runs the firm's private banking and investment group, will gain responsibility for the 15,500-person brokerage as head of Merrill Lynch U.S. Wealth Management starting May 1, according to an internal memo obtained by Bloomberg News. LaMothe said March 4 he's retiring from the Charlotte, North Carolina-based bank to pursue personal interests.

Krawcheck's selection of a Merrill Lynch veteran may solidify her relationship with top members of the brokerage, known as the "Thundering Herd" because of the firm's bull logo. Thiel, 50, started at Merrill as a financial adviser in Tampa, Florida in 1989 and held several management jobs before leading the private bank. Krawcheck, 46, joined Bank of America from New York-based Citigroup Inc. in August 2009.

"John possesses deep wealth-management and Merrill Lynch experience and has a strong commitment to our advisers, our clients and our culture," Krawcheck said in the memo.

The brokerage is the biggest contributor to Krawcheck's operation. Almost 80 percent of the division's $16.7 billion in 2010 revenue came from the adviser group. The unit posted a 4 percent increase in revenue last year to $13.1 billion, or about $854,000 per adviser.

Merrill Lynch Roots

The search for LaMothe's successor focused on managers with roots at Merrill Lynch, two people with knowledge of the process said last month. LaMothe joined Merrill in 1987 as a financial adviser in San Bernardino, California, and held several supervisory jobs before being promoted to head of U.S. wealth management in 2009. Merrill Lynch was taken over by Bank of America at the start of 2009 after subprime-related losses weakened the firm's capital.

Thiel joined Merrill's private-banking and investment group, which caters to the wealthiest individuals, in 2000 and opened the firm's Pacific West department as a regional director based in San Francisco. The private-banking unit has more than $160 billion in assets, according to the memo.

He won the appointment over Andrew Sieg, who runs the division's retirement services operations. Sieg joined Merrill Lynch in 1992 as an analyst in the firm's private-client group, and at one point reported to Krawcheck while both were at Citigroup. He was hired to join Bank of America in 2009.