Pressure‐dependent adaptation strategies implied by the dissimilatory iron reducer Orenia metallireducens Z6

Impact statement Tolerance of high hydrostatic pressure (HHP) is the hallmark of deep subsurface microorganisms, while its mechanisms remain under‐investigated. This study explores HHP adaptation in the piezotolerant bacterium Orenia metallireducens across its near‐full pressure range (0.1–40 MPa). At inhibitory pressure (40 MPa), the organism redirected carbon flux toward more favorable energy generation and biosynthesis using ferric mineral as the “electron sink.” Furthermore, both universal and pressure‐dependent strategies enabled the organism to withstand varying pressures. These findings highlight the role of iron minerals in microbial HHP adaptation and reveal novel survival strategies, advancing our understanding of deep‐life evolution and biogeochemical impacts.