This NSF MRI RAPID project will support the acquisition of a state-of-the art instrument to elucidate the microbial mechanisms of methane and complex petroleum hydrocarbon biodegradation at the quantitative proteomics level. The mechanistic information thus obtained will be used to develop bioremediation strategies to alleviate the environmental insults that have resulted from the Deepwater Horizon oil spill in the Gulf of Mexico. The Deepwater Horizon oil spill has resulted in drastically impaired aquatic life and environmental health of the gulf. Nevertheless, the specific chemical composition of the contaminant stream presents a novel opportunity for simultaneous bioremediation of both the primary organics (the petroleum hydrocarbons) and the methane (the purported cause of the explosion that led to the spill). Methane is typically the primary energy substrate for methane oxidizing bacteria (MOB). However, owing to the broad substrate specificity of the first enzyme involved in methane oxidation to formaldehyde (methane monooxygenase), MOB can oxidize not only methane but also alternate organic substrates such as longer chain aliphatic and aromatic compounds. However, MOB cannot derive energy from such transformations, which are termed ?co-metabolic?. Co-metabolism based bioremediation strategies are therefore characterized by a finite transformation capacity, limited by availability of the primary substrate (in casu, methane).
In this project, they will elucidate the proteomics scale mechanisms of MOB to oxidize methane (via primary energy metabolism) and the mix of petroleum hydrocarbons (via co-metabolism) in lab-scale bioreactors. This NSF MRI Rapid project will support the acquisition of a quantitative proteomics analyzer (Waters Corp.), which will be housed initially for six-months in Earth and Environmental Engineering (the home department of the PI, Dr. Kartik Chandran) and then deployed onsite in the Gulf. When used for ex-situ bioremediation of the sequestered or skimmed pollutants along with the methane (which is currently just being flared or released), the bio-process technology developed in this project could be specifically applied to address both contaminants simultaneously. Mathematical models that describe methane oxidation and co-metabolism of petroleum hydrocarbons will be constructed and parameterized using the proteomics data combined with chemical profiles and microbial measurements. Finally, operating strategies, ex-situ transformation and mineralization of methane and petroleum hydrocarbons mixes obtained on site will be developed and tested.
Successful application of this project will enable the accelerated biological treatment of the widespread petroleum hydrocarbon and methane pollution in the Gulf of Mexico. Additionally, the developed strategies will help to accelerate treatment and minimize such widespread dissemination of this particular contaminant mix, which is typical of offshore drilling operations in the future.
This instrument will be used for Gulf oil spill related research in a timely fashion consistent with RAPID funding requirements.
This NSF MRI RAPID project supported the acquisition of a state-of-the art instrument to elucidate the microbial mechanisms of methane and complex petroleum hydrocarbon biodegradation at the quantitative proteomics level. The mechanistic information thus obtained is intended to develop bioremediation strategies to alleviate the environmental insults that resulted from the Deepwater Horizon oil spill in the Gulf of Mexico in 2010. The Deepwater Horizon oil spill in 2010 resulted in drastically impaired aquatic life and environmental health of the gulf. Nevertheless, the specific chemical composition of the contaminant stream presented a novel opportunity for simultaneous bioremediation of both the primary organics (the petroleum hydrocarbons) and the methane (the purported cause of the explosion that led to the spill). Methane is typically the primary energy substrate for methane oxidizing bacteria (MOB). However, owing to the broad substrate specificity of the first enzyme involved in methane oxidation to formaldehyde (methane monooxygenase), MOB can oxidize not only methane but also alternate organic substrates such as longer chain aliphatic and aromatic compounds. However, MOB cannot derive energy from such transformations, which are termed ‘co-metabolic’. Co-metabolism based bioremediation strategies are therefore characterized by a finite transformation capacity, limited by availability of the primary substrate (in casu, methane). In this project, we have elucidated the proteomics scale mechanisms of autotrophic ammonia oxidizing bacteria, which are closely evolutionarily linked to MOB to oxidize methane (via co-metabolism) in lab-scale bioreactors. We have also used the proteomics analyzer to elucidate mechanisms by which AOB respond to varying dissolved oxygen levels- as they would encounter in the ocean waters. The quantitative proteomics analyzer (Waters Corp.), has been housed permanently at Columbia University, where all the analysis has been carried out. We are also engaged in the development of microbial reactor designs, which are informed by the proteomics and whole-cell level information. When used for ex-situ bioremediation of the sequestered or skimmed pollutants along with the methane (which is currently just being flared or released), the bio-process technology designs developed in this project could be specifically applied to address both contaminants simultaneously. The work so far has mainly been restricted to lab-scale research and analysis owing to the paucity of field-scale samples. We continue to pursue mechanisms to obtain such samples and will interrogate such samples using the proteomics analyzer as they become available. We are also reaching out to other sites across the world, which have been subjected to petroleum hydrocarbon discharges to determine common microbial responses across sites. Project Significance Successful application of this project will enable the accelerated biological treatment of the widespread petroleum hydrocarbon and methane pollution in the Gulf of Mexico. Additionally, the developed strategies will help to accelerate treatment and minimize such widespread dissemination of this particular contaminant mix, which is typical of offshore drilling operations in the future.
