Nitrification of Oxime Compounds by Heterotrophic Bacteria

Abstract

SUMMARY: Production of nitrite from the oxime of pyruvic acid was observed with three groups of heterotrophic soil bacteria : Nocardia corallina, Alcaligenes spp. and Agrobacterium spp. The first could nitrify up to 64 % of the oxime-nitrogen in an inorganic salts solution, the second and third up to 43 and 36 yo, respectively.Glucose inhibited nitrification by stimulating the synthesis of cell substance ; nitrification by Nocardia corallina ceased at C:N ratios above 20 : 1. Approximately 75-90 yo of the oxime-nitrogen was recovered as nitrite + cell-nitrogen in cultures of Nocardiaand Alcaligenes spp. In peptone medium Nocardia corallina converted the oxime almost quantitatively to nitrite ; the rate of nitrite production was parallel with that of cell multiplication. Alcaligenes and Agrobacterium spp. caused a further removal of the nitrite in peptone medium, the latter organism by denitrification. The oxime of oxaloacetic acid was readily nitrified by Alcaligenes spp. Acetoxime was only nitrified to a slight extent and free hydroxylamine apparently not at all. Several other organisms, of which Corynebacterium equi was a possible exception, did not nitrify pyruvic acid oxime.

Heterotrophic nitrification by a thermophilicBacillusspecies as influenced by different culture conditions

“…It is known that heterotrophic nitrification generally proceeds more rapidly on reduced substrates such as organic acids, thus it is not surprising to see that the highly oxidized glucose gave the lowest nitrification rates. Besides, a similar inhibition has previously been described (Jensen 1951;Fisher et al 1956). In the complex organic media, MS30 growth was stimulated, but its nitrification activity was inhibited.…”

Fungi of a forest soil nitrifying at low pH values

“…Oximes are found in many organisms [34,35] but concentrations are as low as 0.05 mg oxime-N • kg-1 in autolysing plant material. We could find no suggestion in the literature that oximes or hydroxylamine might be produced in considerable amounts during humus degradation [36][37][38].…”

Pyruvic oxime dioxygenase from heterotrophic nitrifier Alcaligenes faecalis is a nonheme Fe(II)-dependent enzyme homologous to class II aldolase

“…In the mid-20 th century, the relevance of oxime and nitro compounds to nitrification in several heterotrophic microorganisms was reported15161718. Alcaligenes faecalis is a betaproteobacterium that has been commonly used for investigation of heterotrophic nitrification, and pyruvic oxime (2-(hydroxyimino)propanoic acid), and not its hydrolysis product, NH 2 OH, was found to be involved in the ammonia oxidation pathway of A. faecalis 6.…”