Respiratory inhibitors of a magnetic bacterium Magnetospirillum sp. AMB-1 capable of growing aerobically

Respiratory inhibitors of a magnetic bacterium Magnetospirillum sp. AMB-1, which is able to grow aerobically, were investigated using a microbial electrode system. The respiration of strain AMB-1 was inhibited by 2-heptyl-4-hydroxyquinoline N-oxide (HQNO), KCN and dicumarol. Strain AMB-1 cannot grow in the presence of these inhibitors under aerobic conditions. On the other hand, strain AMB-1 can grow and form magnetite (Fe₃O₄) particles with HQNO and KCN under anaerobic conditions. Growth and magnetite formation of strain AMB-1 were reduced by dicumarol, which also inhibited iron reduction under anaerobic conditions, whereas iron reduction was not inhibited by HQNO and KCN.