s-Triazines as nitrogen sources for bacteria

Abstract

Isolation of bacteria able to utilize s-triazines as the sole and limiting nitrogen sources for growth is described. Three strains of Pseudomonas (A, D, and F) and two strains of Klebsiella pneumoniae (90 and 99) were examined. Strains D and F utilized N-ethylammelide, N-isopropylammelide, ammeline, ammelide, cyanuric acid, and ammonium ion as nitrogen sources. Strain A utilized melamine, ammeline, ammelide, cyanuric acid, ammonium ion, and deaminated N-ethylammeline and N-isopropylammeline. Strains 90 and 99 utilized ammelide, cyanuric acid, and ammonium ion. Growth yields of strains were independent of the nitrogen source, and specific growth rates with s-triazines were similar to those with ammonium ion as the nitrogen source (-0.3-0.6 h-l). Suspensions of nongrowing cells generally gave quantitative yields of ammonium ion from s-triazines, and ring carbon atoms were released as carbon dioxide. N-Alkylammelines in mixtures of strains A and D were quantitatively degraded to ammonium ion.Papers claiming microbial degradation of s-triazines, usually herbicides, are widespread, but reviewers have various interpretations of the rates of s-triazine degradation. Thus Alexander (1979) labels s-triazines recalcitrant, Cripps and Roberts (1978) imply ready degradability, whereas other reviewers refrain from comment (Esser et al., 1975;Kaufman and Kearney, 1970; Knuesli et al., 1969; Mikrobiologisches Institut, Eidgenossische Technische Hochschule, ETH-Zentnun, CH-8092 Zurich, Switzerland. Harris et al., 1968). Jordan et al. (1970) complement these data by citing extensive nonbiological degradation of striazines, usually on clay mineral surfaces. s-Triazines do not accumulate in the soils studied by Ramsteiner et al. (1972).Metabolites from s-triazines in experiments with animals, plants, and microorganisms have been reviewed by Fishbein (1975). Definitive proof of s-triazine metabolism by microorganisms in pure culture has been provided

Different bacterial strategies to degrade taurocholate

“…Growth was followed as turbidity at 580 nm or quantiWed as protein in a Lowry-type reaction (Cook and Hütter 1981). Sulfate was determined turbidimetrically as a suspension of BaSO 4 (Sörbo 1987); samples containing taurocholate had to be diluted, to prevent taurocholic acid (>0.25 mM) forming a precipitate.…”

Sulfoacetate generated by Rhodopseudomonas palustris from taurine

“…Growth was followed as turbidity (OD 580 =1.0=250 mg protein l -1 ) and quantified as protein in a Lowry-type reaction (Cook and Hütter 1981). Reversed-phase chromatography was used to quantify taurine (Laue et al 1997) or sulfoacetaldehyde (Cunningham et al 1998) after derivatization.…”

Biodegradation of melamine and its hydroxy derivatives by a bacterial consortium containing a novel Nocardioides species

“…Pseudomonas sp. strain A (NRRL B-12227) was isolated as a melamine-utilizing bacterium from municipal sewage collected in Switzerland (Cook and Hütter 1981;Cook 1987) and was later reclassified as Acidovorax citrulli (Seffernick et al 2002;Schaad et al 2008). Another melamine-degrading isolate, Rhodococcus corallinus strain 11 (NRRL B-15444R), was obtained from soils that had been experimentally exposed to s-triazine herbicides for a long time (Cook and Hütter 1984;Cook 1987).…”