Infoscitex investigated biosynthetic approaches toward the generation of nitramines (RDX, HMX) used in explosives. Nitramines are widely used by the U.S. military as key components of contemporary weapons. However, production of these nitroenergetics involves the use of highly concentrated hot nitric and sulfuric acids, results in the emission of nitrogen oxides, and is also a potential health hazard. The development of an alternative process for producing nitro-energetic compounds under milder conditions, in an environmentally friendly manner, and in higher yields is needed.

The objective of this project was to develop microorganisms capable of catalyzing bioconversion (oxidation-nitration) of the common RDX precursor, hexamine, into RDX in presence of nitrite and peroxide.

The project encompassed three main activities:

• Generation of a microbial strain that would be able to convert hexamine into RDX
• Generation of microbially produced RDX
• Characterization of the microbial product

The following outcomes were generated:

• A microbial strain deriving from a known microbial RDX degrader, Rhodococcus strain DN22, was engineered to exhibit elevated levels of cytochrome P450 expression and activity that would be required for hexamine to RDX conversion.
• The biomass of this microorganism was applied to attempt the hexamine to RDX conversion.
• The microbial product was analyzed for presence of RDX by Fourier-transform infrared (FTIR), chromatography, and nuclear magnetic resonance (NMR) spectroscopy.

Formation of RDX was not detected. However, it is possible that some RDX-like intermediates were formed in trace amounts.

The development of an alternative process for producing nitro-energetic compounds under milder conditions, in an environmentally friendly manner, and in higher yields would result in a significant saving and improvement of the quality of life in the surrounding communities.