Degradative capability ofPseudomonas putida on acetonitrile

Pseudomonas putida, capable of utilizing acetonitrile as a sole source of carbon and nitrogen, was isolated from contaminated soil and water samples collected from industrial sites. TheP. putida cells were immobilized in calcium alginate beads. The degradation of acetonitrile by the immobilized cells ofP. putida was investigated. The immobilized cells degraded different concentrations of acetonitrile into ammonia and carbon dioxide. The effect of aeration on the degradation rate was also studied. Oxygen limitation was suggested in the alginate-immobilized system. The rate of degradation of acetonitrile increased with increase in the rate of aeration.     

Effect of temperature and yeast extract on microbial respiration of sediments from a shallow coastal subsurface and vadose zone

Applied Biochemistry and Biotechnology - As a part of our study on microbial heterogeneity in subsurface environments, we have examined the microbial respiration of sediment samples obtained from a...     

Degradation of Organic Cyanides byPseudomonas aeruginosa

A bacterium capable of utilizing acetonitrile (methyl cyanide) as the sole source of carbon and nitrogen was isolated from soil and identified asPseudomonas aeruginosa. This bacterium could also utilize and oxidize numerous lower-mol-wt nitrile compounds and their corresponding amides as growth substrates. A metabolite of acetonitrile in the culture medium was determined to be ammonia. The accumulation of ammonia in the culture medium was proportional to the concentration of the substrate and the inoculum. Cell extracts of the bacterium contained activities corresponding to nitrile aminohydrolase (E C 3.5.5.1) and amidase (E C 3.5.1.4), which regulate the degradation of acetonitrile. Both enzymes were inducible and hydrolyzed a wide range of substrates, and it was determined that the specific activity of amidase was far greater than the activity of nitrile aminohydrolase.     

A kinetic study on the bioremediation of sodium cyanide and acetonitrile by free and immobilized cells ofPseudomonas putida

Pseudomonas putida capable of utilizing organic nitrile (acetonitrile) and inorganic cyanide (sodium cyanide) as the sole source of carbon and nitrogen was isolated from contaminated industrial sites and waste water. The bacterium possesses nitrile aminohydrolase (EC 3.5.5.1) and amidase (EC 3.5.1.4), which are involved in the transformation of cyanides and nitriles into ammonia and CO₂ through the formation of amide as an intermediate. Both of the enzymes have a high selectivity and affinity toward the⁻Cn group. The rate of degradation of aceotnitrile and sodium cyanide to ammonia and CO₂ by the calcium-alginate immobilized cells ofP. putida was studied. The rate of reaction during the biodegradation of acetonitrile and sodium cyanide, and the substrate- and product-dependent kinetics of these toxic compounds were studied using free and immobilized cells ofP. putida and modeled using a simple Michaelis-Menten equation.