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Published on: March 20, 2018
Metabolism of anthracene by a Rhodococcus species
D Dean-Ross1, J D Moody, J P Freeman
1Department of Biology, Indiana University-Purdue University, Fort Wayne, IN 46805, USA. ross@ipwf.edu
FEMS Microbiology Letters
|October 30, 2001
Summary
This study shows a Rhodococcus bacterium can degrade high molecular mass polycyclic aromatic hydrocarbons. It utilizes specific compounds and reveals novel metabolic pathways in Gram-positive bacteria for pollutant breakdown.
Area of Science:
- Environmental Microbiology
- Bioremediation
- Bacterial Metabolism
Background:
- Polycyclic Aromatic Hydrocarbons (PAHs) are persistent environmental pollutants.
- Microbial degradation offers a sustainable bioremediation strategy.
- Rhodococcus species are known for their metabolic versatility.
Purpose of the Study:
- To investigate the degradation capabilities of a Rhodococcus sp. isolated from river sediment.
- To identify the metabolic pathways involved in high molecular mass PAH degradation by this isolate.
Main Methods:
- Isolation and cultivation of Rhodococcus sp. from contaminated river sediment.
- Assessing the utilization of various PAHs as sole carbon and energy sources.
- Identification of metabolic intermediates and ring-fission products using analytical techniques.
Main Results:
- The Rhodococcus sp. efficiently degraded anthracene (53%), phenanthrene (31%), pyrene (13%), and fluoranthene (5%).
- Naphthalene and chrysene were not utilized as carbon sources.
- Two distinct ring-cleavage pathways for anthracene degradation were identified: a meta-cleavage pathway and a novel ortho-cleavage pathway.
Conclusions:
- The isolated Rhodococcus sp. demonstrates significant potential for bioremediating PAH-contaminated environments.
- The identification of a novel ortho-cleavage pathway in Gram-positive bacteria expands our understanding of microbial PAH metabolism.
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