Abstract
BackgroundNitrilases, which hydrolyze nitriles in a one-step reaction into carboxylic acids and ammonia, gained increasing attention because of the abundance of nitrile compounds in nature and their use in fine chemicals and pharmaceutics. Extreme environments are potential habitats for the isolation and characterization of extremozymes including nitrilases with unique resistant properties. The Red Sea brine pools are characterized by multitude of extreme conditions. The Lower Convective Layer (LCL) of the Atlantis II Deep Brine Pool in the Red Sea is characterized by elevated temperature (68 °C), high salt concentrations (250 ‰), anoxic conditions and high heavy metal concentrations.ResultsWe identified and isolated a nitrilase from the Atlantis II Deep Brine Pool in the Red Sea LCL. The isolated 338 amino-acid nitrilase (NitraS-ATII) is part of a highly conserved operon in different bacterial phyla with indiscernible function. The enzyme was cloned, expressed and purified. Characterization of the purified NitraS-ATII revealed its selectivity towards dinitriles, which suggests a possible industrial application in the synthesis of cyanocarboxylic acids. Moreover, NitraS-ATII showed higher thermal stability compared to a closely related nitrilase, in addition to its observed tolerance towards high concentrations of selected heavy metals.ConclusionThis enzyme sheds light on evolution of microbes in the Atlantis II Deep LCL to adapt to the diverse extreme environment and can prove to be valuable in bioremediation processes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12896-016-0244-2) contains supplementary material, which is available to authorized users.
Highlights
Nitrilases, which hydrolyze nitriles in a one-step reaction into carboxylic acids and ammonia, gained increasing attention because of the abundance of nitrile compounds in nature and their use in fine chemicals and pharmaceutics
Our results have shown that NitraS-Atlantis II Deep (ATII) has higher thermal stability than R. sphaeroides LHS-305 nitrilase and is highly tolerant to different heavy metals
open reading frame (ORF) in the operon were compared to NCBI non-redundant protein database using BLASTp [27] and subsequently annotated as follows: conserved hypothetical protein, putative nitrilase, putative radical SAM-domain containing protein, putative acetyltransferase, selenophosphate synthetase-related protein (AIR synthetase-related protein), conserved hypothetical protein, putative FADdependent oxidoreductase, conserved hypothetical protein and putative methylmalonyl-CoA mutase
Summary
Nitrilases, which hydrolyze nitriles in a one-step reaction into carboxylic acids and ammonia, gained increasing attention because of the abundance of nitrile compounds in nature and their use in fine chemicals and pharmaceutics. The Red Sea brine pools are characterized by multitude of extreme conditions. The Lower Convective Layer (LCL) of the Atlantis II Deep Brine Pool in the Red Sea is characterized by elevated temperature (68 °C), high salt concentrations (250 ‰), anoxic conditions and high heavy metal concentrations. Nitriles are organic compounds that contain a cyano (CN) functional group These compounds are abundant in nature, produced by selected plants, animals [1], bacteria, fungi and algae [2]. Processing of nitriles can occur either chemically or enzymatically To this end, nitrilases (EC 3.5.5.1) are one of the most important enzymes as they hydrolyze nitriles (R-CN) directly into their corresponding carboxylic acids (R-COOH) and ammonia (NH3) [1, 3, 4]. Members of this superfamily are classified into 13 subgroups and are involved in non-peptide C-N
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
