title: Expression of carotenoid pigments of haloarchaeal cultures exposed to aniline.
abstract: The effects of exposure to aniline on growth and pigmentation in three haloarchaeal isolates from the Indian subcontinent--GUSF (MTCC 3265), from the estuarine saltpans of Goa, India; and GURFT-1 and GURFP-1, both from continental shelf sediments of the west coast of India--were studied. In nutrient-rich tryptone yeast extract medium containing 25% NaCl/crude salt, the growth of GUSF, measured as absorbance at 600 nm, was not affected significantly at all concentrations of aniline used [0.005%-0.04% (v/v)], whereas the growth phases of GURFT-1 and GURFP-1 were affected at concentrations > 0.005%; the total yield, however, was nearly equal to the yield of cultures growing in the absence of aniline. GURFT-1 reached approximately 40% of total yield on the 7th day in the presence of 0.04% aniline, which declined thereafter. The pigmentation observed visually was completely abolished at concentrations of aniline greater than 0.01%. Spectral scans of acetone extracts of the pigment of each of the cultures exposed to concentrations of aniline > 0.01% showed that (i) the bacterioruberin component of the pigments (absorbance in the range 390-500 nm) was completely abolished and (ii) the pigment component(s) shifted toward squalene and phytofluene derivatives (320-360 nm). This is the first report examining the effect of an aromatic pollutant such as aniline on the growth and pigmentation of haloarchaeal cultures.
authors.affiliation: Department of Microbiology, Goa University, Goa 403 206, India.
authors.forename: T M
authors.initials: TM
authors.lastname: Raghavan
authors.forename: I
authors.initials: I
authors.lastname: Furtado
mesh_terms: D000814:Aniline Compounds / Q000633:toxicity*; D002273:Carcinogens / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D019605:Euryarchaeota / Q000737:chemistry* / Q000254:growth & development*; D007194:India; D010860:Pigments, Biological / Q000096:biosynthesis*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D000814:Aniline Compounds; D002273:Carcinogens; D010860:Pigments, Biological; D014874:Water Pollutants, Chemical; C023650:aniline