SAO PAULO, March 19 (Reuters) - Brazilian state-run oil company Petrobras said on Tuesday that it signed a memorandum of understanding with Mitsui & Co to study low-carbon business opportunities in Brazil, including on sustainable hydrogen and biomethane.

The memorandum was signed during the CERAWeek energy conference in Houston, Petrobras said in a securities filing. (Reporting by Andre Romani; Editing by Leslie Adler)