By Anthony Boadle
BRASILIA (Reuters) - Brazilian President Michel Temer appointed a lower house lawmaker from his ruling PMDB party, Osmar Serraglio, to be justice minister on Thursday, a choice aimed at appeasing disgruntled members of his party.
Temer's spokesman said Serraglio, 68, had accepted the job.
PMDB lawmakers, whose support is vital for passage of Temer's unpopular austerity measures, were unhappy he had too many members from allied parties in his cabinet and pushed for inclusion of one of their own.
Reuters reported earlier on Thursday that Serraglio was tipped for the post. Serraglio succeeds Alexandre de Moraes who was confirmed by the Senate to become a Supreme Court justice on Wednesday.
Serraglio, a five-term congressman from Paraná state, was an ally of former lower chamber speaker Eduardo Cunha, who was stripped of his seat and arrested last year on corruption charges.
Serraglio has said that, if appointed, he would not interfere in the investigations under way in Brazil's biggest ever graft scandal that threatens to ensnare dozens of politicians for allegedly taking kickbacks from engineering firms seeking government contracts.
"The president had to deal with the malaise in his party," a Temer aide told Reuters on condition of anonymity because he was not authorized to speak about the appointment.
Temer enjoys a majority in Congress, but some PMDB lawmakers want to water down his proposal for reform of Brazil's costly pension system, a key item on his agenda to restore fiscal discipline and business confident in a stagnant economy.
The first signs of revolt appeared on Thursday when lawmaker Fabio Ramalho said he was breaking with Temer because the PMDB caucus from his state of Minas Gerais had been overlooked in the distribution of cabinet posts.
"The appointment of Serraglio was the last drop," Ramalho, who is deputy speaker of the lower chamber, told Reuters. "Most of us will vote against the pension reform as sent here. It will have to be changed."
(Additional reporting by Lisandra Paraguassu and Maria Carolina Marcello; Editing by Cynthia Osterman and James Dalgleish)