Heterotrophic inorganic carbon fixation varies with temperature and resource availability in marine and soil bacterial isolates.

Heterotrophic bacteria from soil and marine environments show variable inorganic carbon fixation rates influenced by temperature and resource availability, with P. carrageenovora reaching up to 1.1%.

• Why it matters: Understanding heterotrophic inorganic carbon fixation (HICF) is crucial because it may significantly contribute to global carbon cycling, yet its controls in heterotrophic microorganisms are poorly understood.
• What they did: The study cultivated Pseudomonas putida and Pseudoalteromonas carrageenovora under different temperatures and resource conditions, using stable isotope probing to quantify HICF and assess metabolic states at the bulk and single-cell levels.
• The result: HICF was detected across all conditions, generally highest during exponential growth at optimal temperatures and low carbon levels, indicating that environmental factors influence heterotrophic inorganic carbon incorporation and its potential role in carbon cycling.