‘OIL-EATING’ ALCANIVORAX BORKUMENSIS BACTERIA

Context

The role of a specific type of bacteria called Alcanivorax borkumensis (Alca) in enhancing the biodegradation of oil.

Details

• The passage discusses the role of Alcanivorax borkumensis bacteria, also known as Alca, in enhancing the biodegradation of oil.
• The researchers have discovered how these bacteria optimize oil consumption through the formation of dendritic biofilms around oil droplets.

Oil-Degrading Bacteria - Alcanivorax borkumensis

• Alcanivorax borkumensis bacteria are categorized as obligately hydrocarbonoclastic bacteria (OHCB) due to their ability to consume hydrocarbons as their sole carbon and energy source.
• OHCB, like Alca, play a crucial role in the bioremediation of petroleum spills worldwide.

Bloom During Oil Spills

• Alca, a rod-shaped and aerobic OHCB, thrives on organic acids and alkanes present in crude oil.
• During oil spills, Alca populations bloom to exploit the hydrocarbons within the spilled oil.

Role of Biofilm Formation

• Alca bacteria form biofilms around oil droplets during the consumption of alkanes.
• The function of biofilm formation in oil consumption by Alca remains unclear.

Microfluidic Device for Observation

• Researchers developed a microfluidic device for real-time imaging of bacteria-covered oil droplets.
• This device enabled the observation of biofilm development dynamics, from initial colonization to complete consumption of oil droplets.

Shift in Biofilm Morphology

• Researchers noticed a change in biofilm morphology based on adaptations to oil consumption.
• Newly exposed cultures formed thick spherical biofilms growing outward from the oil, while longer-exposed cultures developed thin biofilms with dendritic finger-like protrusions.

Dendritic Biofilms and Consumption Optimization

• Dendritic biofilms altered oil-water interfacial tension, reshaping oil droplets as bacterial cells proliferated.
• This reshaping increased the droplet's surface area, allowing more bacteria to feed simultaneously.
• Alca's efficiency in oil consumption was optimized by expanding the interfacial properties of the droplets.

Multi-Species Microbial Community

• The research emphasizes that Alca alone cannot degrade the numerous hydrocarbons in crude oil.
• The degradation process requires a diverse microbial community that interacts and sometimes competes with each other.

Broader Implications and Future Directions

• The findings provide insights into the mechanisms that drive oil biodegradation and transport in oceans.
• Expanding the understanding from micro-scale interactions to macro-scaled multi-species processes can enhance our knowledge of oil spill mitigation.

https://www.eurekalert.org/news-releases/998434