Effective Strategies for Enhancing Carbon Monoxide Oxidation in Microorganisms

Role of Carboxydovores in Volcanic Ecosystems

Carboxydovores are specialized microorganisms that utilize carbon monoxide as a primary energy source. They are particularly abundant in volcanic ecosystems where CO is produced from geothermal emissions. Recent studies have highlighted the significance of carboxydovores in these environments, demonstrating their ability to thrive despite extreme conditions such as high temperatures and fluctuating pH levels (Dawson et al., 2025). In volcanic deposits, CO-oxidizing bacteria, including members of the Burkholderiaceae family, play a crucial role in carbon cycling and microbial community dynamics.

Carboxydovores have been shown to possess unique adaptations that allow them to efficiently oxidize CO. For example, isolates such as Cupriavidus ulmosensis and Paraburkholderia terrae demonstrate metabolic flexibility, enabling them to utilize CO across a wide range of concentrations (Dawson et al., 2025). This metabolic versatility is essential for their survival in nutrient-limited environments, where they can switch between different energy sources depending on availability.

Physiological and Metabolic Characteristics of Carbon Oxidizers

The physiological and metabolic characteristics of carbon oxidizers are fundamental to their ability to thrive in harsh environments. CO-oxidizing microorganisms typically possess carbon monoxide dehydrogenases (CODHs), which are pivotal in the oxidation of CO to carbon dioxide. These enzymes are categorized into two types based on their metal co-factors: molybdenum-copper (Mo-Cu) and nickel-iron (Ni-Fe) CODHs, with Mo-Cu CODHs being more common among aerobic carboxydovores (Dawson et al., 2025).

Studies have revealed that carboxydovores exhibit distinct metabolic pathways that enable them to utilize CO in combination with other substrates. For instance, Cupriavidus ulmosensis can grow in the presence of both CO and organic carbon, optimizing energy production through a mixotrophic lifestyle. In contrast, Paraburkholderia terrae is capable of oxidizing CO even in the absence of additional carbon sources, indicating its adaptability to extreme conditions (Dawson et al., 2025).

Table 1: Physiological Characteristics of Key CO-Oxidizing Bacteria

Innovations in Isolating and Cultivating CO-Oxidizing Bacteria

The isolation and cultivation of CO-oxidizing bacteria have advanced significantly in recent years. Targeted enrichment techniques have been developed to enhance the recovery of carboxydovores from complex environmental samples, such as volcanic deposits. By utilizing modified media that simulate low CO concentrations, researchers have isolated new strains capable of efficient CO oxidation (Dawson et al., 2025).

For example, a modified isolation method was successfully employed to target bacteria that utilize low concentrations of CO as a supplementary energy source, leading to the discovery of novel species like Cupriavidus ulmosensis and Paraburkholderia terrae (Dawson et al., 2025). These innovations not only expand the diversity of known carboxydovores but also enhance the understanding of their ecological roles and metabolic strategies.

Figure 1: Isolation Process of CO-Oxidizing Bacteria

Implications of Carbon Monoxide Utilization for Environmental Microbiology

The ability of microorganisms to oxidize carbon monoxide has significant implications for environmental microbiology. CO-oxidizing bacteria contribute to carbon cycling in various ecosystems, impacting soil health and nutrient availability. Their role in volcanic ecosystems is particularly noteworthy, as these microorganisms help stabilize carbon emissions and enhance soil formation processes (Dawson et al., 2025).

Furthermore, the metabolic pathways utilized by carboxydovores can influence the composition and diversity of microbial communities in their respective environments. Understanding these interactions is crucial for developing strategies to manage ecosystems affected by volcanic activity and for promoting sustainable practices in carbon management.

Frequently Asked Questions (FAQ)

What are carboxydovores?

Carboxydovores are microorganisms that utilize carbon monoxide as their primary energy source, playing a significant role in carbon cycling within ecosystems.

How do CO-oxidizing bacteria contribute to volcanic ecosystems?

These bacteria help stabilize carbon emissions from volcanic activity and enhance the formation of soils by participating in nutrient cycling.

What innovations have been made in isolating CO-oxidizing bacteria?

Recent advancements include targeted enrichment techniques that allow for the recovery of novel strains from complex environments, enhancing the understanding of their metabolic strategies.

Why is understanding carbon monoxide oxidation important for environmental microbiology?

Understanding CO oxidation is crucial for managing ecosystems, improving soil health, and developing sustainable carbon management practices.

How do the physiological characteristics of CO-oxidizing bacteria vary?

Physiological characteristics, such as the type of carbon monoxide dehydrogenase and growth conditions, can vary among different CO-oxidizing bacteria, influencing their ecological roles and metabolic flexibility.

References

1. Dawson, R. A., Fantom, N., Martin-Pozas, T., Aguila, P., King, G. M., & Hernández, M. (2025). Carbon monoxide-oxidising Pseudomonadota on volcanic deposits. Environmental Microbiome. https://doi.org/10.1186/s40793-025-00672-y

2. Zhao, F., Yuan, M., Keating, C., Shaabani, N., Limbo, O., Joyce, C., Woehl, J., Barman, S., Burns, A., Tran, Q., Zhu, X., Ricciardi, M., Peng, L., Smith, J., Huang, D., Briney, B., Sok, D., Nemazee, D., Teijaro, J. R., Wilson, I. A., Burton, D. R., & Jardine, J. G. (2025). Broadening a SARS-CoV-1–neutralizing antibody for potent SARS-CoV-2 neutralization through directed evolution

3. Xu, S., Chen, J., Yue, S., Zhang, Y., Zhao, S., Hu, Y., Zhang, C., Guan, W., Zhang, L., Zhang, L., & Liang, C. (2025). Alcohol intake exacerbates experimental autoimmune prostatitis through activating PI3K/AKT/mTOR pathway-mediated Th1 differentiation. Frontiers in Immunology. https://doi.org/10.3389/fimmu.2024.1512456

4. Xie, L., Hu, W., Zhang, H., Ding, Y., Zeng, Q., Liao, X., Wang, D., & Xie, W. (2023). Single-nucleus RNA sequencing reveals heterogeneity among multiple white adipose tissue depots

5. Li, Z. Q., Gao, Y. T., Zhao, C. F., An, R., Wu, Y. L., Huang, Z. P., Ma, P., Yang, X. Y. (2025). Antioxidant and anti-inflammatory function of walnut green husk aqueous extract (WNGH-AE) on human hepatocellular carcinoma cells (HepG2) treated with t-BHP. PLoS One. https://doi.org/10.1371/journal.pone.0318005