Cupriavidus

Cupriavidus necator

Cupriavidus is a genus of bacteria within the family Burkholderiaceae. The members of this genus are Gram-negative, motile, rod-shaped bacteria that are notable for their resistance to heavy metals, including compounds of copper, cadmium, zinc, and mercury. This characteristic makes them of interest in the field of bioremediation, where they are studied and utilized for the cleanup of heavy metal-contaminated environments.

Characteristics

Cupriavidus bacteria are aerobic, capable of using oxygen to break down organic materials for energy. They are also versatile in their metabolic capabilities, able to degrade a wide range of organic compounds, which contributes to their survival in diverse environments. Some species within this genus can fix nitrogen, converting atmospheric nitrogen into ammonia, a process that is crucial for nutrient cycling in ecosystems.

Taxonomy

The genus Cupriavidus was previously included in the genus Ralstonia, but phylogenetic studies based on 16S rRNA gene sequences have led to the reclassification of some species into the new genus Cupriavidus. This reclassification is part of an ongoing effort to refine bacterial taxonomy based on genetic information.

Environmental and Biotechnological Applications

Due to their heavy metal resistance, Cupriavidus species are studied for their potential in bioremediation projects. For example, Cupriavidus metallidurans is known for its ability to tolerate high concentrations of heavy metals and has been researched for its use in cleaning up environments contaminated with these toxic substances. Additionally, some species are being explored for their ability to promote plant growth by fixing nitrogen and solubilizing phosphate, making them beneficial in agriculture as biofertilizers.

Health Implications

While Cupriavidus species are primarily studied for their environmental applications, there have been instances where they have been identified as opportunistic pathogens in humans, particularly in individuals with compromised immune systems. However, such infections are rare.

Species

The genus Cupriavidus includes several species, such as:

• Cupriavidus metallidurans
• Cupriavidus basilensis
• Cupriavidus campinensis
• Cupriavidus gilardii
• Cupriavidus necator (also known for its role in bioplastics production)
• Cupriavidus oxalaticus
• Cupriavidus pauculus
• Cupriavidus respiraculi

See Also

• Bioremediation
• Heavy metal pollution
• Microbial biotechnology
• Nitrogen fixation