Degradation of 1,4-dioxane by an actinomycete in pure culture

Abstract

An actinomycete capable of sustained aerobic growth on 1,4-dioxane was isolated from a dioxanecontaminated sludge sample. The actinomycete, CB1190, grows on 1,4-dioxane as the sole carbon and energy source with a generation time of approximately 30 h. CB1190 degrades 1,4-dioxane at a rate of 0.33 mg of dioxane min-' mg of protein-' and mineralizes 59.5% of the dioxane to CO2. CB1190 also grows with other cyclic and linear ethers as the sole carbon and energy sources, including 1,3-dioxane, 2-methyl-1,3-dioxolane, tetrahydrofuran, tetrahydropyran, diethyl ether, and butyl methyl ether. CB1190 is capable of aerobic autotrophic growth on H2 and CO2.

Bioleaching of rare earth elements from monazite sand

“…Growth medium composition and carbon source varied with each experiment. Four different media were used: NBRIP medium (Nautiyal, 1999), modified Pikovskaya medium (PVK medium) (Nautiyal, 1999;Pikovskaya, 1948), PVK medium without Mn and Fe, and modified ammonium salts medium (AMS medium) (Parales et al, 1994). See Table I for media compositions.…”

RubisCO‐based CO2 fixation and C1 metabolism in the actinobacterium Pseudonocardia dioxanivorans CB1190

“…CO2 fixation is energetically costly, and autotrophic microorganisms have evolved mechanisms to utilize a variety of electron donors (Hügler and Sievert, 2011). Autotrophic growth by CB1190 was originally identified with H2 as the electron donor (Parales et al, 1994). We tested if ammonia, nitrite, thiosulfate (under ambient air or microaerophilic conditions) or formate could support CB1190 autotrophic growth with bicarbonate, but only growth with formate/bicarbonate was observed after 1 month under the tested conditions.…”

“…Strain CB1190 for microarray analysis was obtained from Rebecca Parales (UC Davis) and was cultivated in ammonium mineral salts (AMS) medium (Parales et al, 1994). Serum bottles (160 ml) were prepared with 50 ml AMS medium, were amended with sodium pyruvate (31 mM) or sodium bicarbonate (36 mM), and were sealed with black butyl rubber stoppers.…”

“…Pseudonocardia dioxanivorans CB1190 (Mahendra and Alvarez-Cohen, 2005) is an additional strain in the genus Pseudonocardia that can fix CO 2. CB1190 was isolated from industrial sludge contaminated with 1,4-dioxane, and it is notable for its rare ability to use 1,4-dioxane as a sole source of carbon and energy (Parales et al, 1994). In CB1190, CO2 fixation can occur anaplerotically [as happens during growth with 1,4-dioxane (Grostern et al, 2012)], or it can support biomass growth when H2 is supplied as an energy source (Parales et al, 1994).…”

“…CB1190 was isolated from industrial sludge contaminated with 1,4-dioxane, and it is notable for its rare ability to use 1,4-dioxane as a sole source of carbon and energy (Parales et al, 1994). In CB1190, CO2 fixation can occur anaplerotically [as happens during growth with 1,4-dioxane (Grostern et al, 2012)], or it can support biomass growth when H2 is supplied as an energy source (Parales et al, 1994). The genome of CB1190 was recently sequenced (Sales et al, 2011) in order to gain specific insights into 1,4-dioxane metabolism, as well as to learn about general metabolism in Pseudonocardia.…”