(Recasts lead, adds purpose of the spacewalk in paragraph 2)
MISSION CONTROL (Moscow Region), June 6 (RIA Novosti) - Russian cosmonauts Fyodor Yurchikhin and Oleg Kotov Wednesday began the second spacewalk of their current mission at the world's sole orbital station for maintenance operations and experiments, Russia's Mission Control said.
Apart from routine maintenance, the cosmonauts will install the Biorisk-MSN bacteriological module in open space to study how different strains of bacteria survive intense radiation.
U.S. astronaut Sunita Williams will stay onboard the International Space Station during the 5 hour 50 minute spacewalk to back up the two Russians, who will be working in Russian-made Orlan-M spacesuits.
