Abstract
Halogenated alkanes constitute a significant group among the organic pollutants of environmental concern. Their industrial and agricultural uses are extensive, but until 1978 they were considered to be non-biodegradable. In recent years, microorganisms were described that could degrade, partially or fully, singly or in consortia, many of the compounds tested. The first step in haloalkane degradation appears to be universal: removal of the halogen atom(s). This is mediated by a group of enzymes, generally known as dehalogenases, acting in most cases either as halidohydrolases or oxygenases. Nevertheless, information is still severely lacking regarding the biochemical pathways involved in these processes, as well as their genetic control. A recently isolated Pseudomonas strain, named ES-2, was shown to possess a very wide degradative spectrum, and to contain at least one hydrolytic dehalogenase. The utilization by this organism of water-insoluble haloalkanes, such as 1-bromooctane, appears to consist of three phases: extracellular emulsification by a constitutively excreted surface active agent, periplasmic dehalogenation by an inducible dehalogenase, and intracellular degradation of the residual carbon skeleton.
Original language | English |
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Pages (from-to) | 299-313 |
Number of pages | 15 |
Journal | Biodegradation |
Volume | 3 |
Issue number | 2-3 |
DOIs | |
State | Published - Jun 1992 |
Externally published | Yes |
Keywords
- biodegradation
- bromoalkanes
- dehalogenase
- environmental pollution
- haloalkanes
- Pseudomonas sp.