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Cyanide is a potent poison that can be found naturally in some environments, and released as a waste in human activities.Cyanide waste is indeed a public health and an environmental concern.Its removal is an important issue that has been addressed by chemical/physical methods or by alternatives, such as bioremediation, that utilize organisms that can degrade cyanide.Pseudomonas fluorescens NCIMB11764 (Pf11764) bacterium is capable of utilizing cyanide as its sole nitrogen source.However, the complete pathways involved in its metabolism are unclear.To understand the genetic features of Pf11764, we sequenced the bacteriums genome and identified the genes involved in cyanide degradation.Our results showed that the genome of Pf11764 has metabolic capabilities similar to the Pseudomonas fluorescens species; however, specific cyanide degradation and cyanide resistance pathways were also identified.Specifically, we discovered the nitC cluster and cyanatehydratase enzymes in the genome.We alsoidentified candidates for two of the four enzyme components of the cyanide oxygenase (CNO) complex.In addition, we observed and proposed cyanide resistance pathways through the presence of the nir operon.We hypothesized that the nir operon might perform a double function for cyanide protection: (1) by directly binding cyanide to the NirS protein in order to prevent cyanides toxic effects, and (2) by production of NO (Nitrous oxide), which is a cyanide antagonist.Such resistance genes might be necessary for cyanide-degrading bacteria to survive in contaminated environments.We believe it is possible to use Pf11764 or other genetically modified bacteria with cyanide degrading genes as a bioremediation process for removing cyanide from the environments.