title: Mercury bioremoval by Yarrowia strains isolated from sediments of mercury-polluted estuarine water.
abstract: Difference in mercuric ion removal by resting and growing cells of two mercury-resistant yeast strains, identified as Yarrowia spp. (strains Idd1 and Idd2), were studied. Resting cells of strain Idd2 exhibited high maximum Hg(2+) removal capacity (59 mg mercury per g dry cell weight [gdw(-1)]) by adsorption than those of resting cells of strain Idd1 (32 mg gdw(-1)). The resting cells of strain Idd2 exhibited a higher Hg(2+) desorption capacity using CaCl2 (68 %) and EDTA (48 %) than strain Idd1, depicting weaker binding of Hg(2+) onto strain Idd2 unlike strain Idd1. The actively growing yeast cells showed opposite Hg removal characteristics to those of the resting cells. Strain Idd1 adsorbed less Hg(2+) from culture medium supplemented with Hg(2+) than strain Idd2. However, the growing strain Idd1 reduced and vaporized 27 % of supplemented Hg(2+) as metallic mercury (Hg(0)), while the growing strains Idd2 vaporized 15 % of the supplemented Hg(2+). These two yeast strains are potential biotechnological tools for the eventual bioremediation of polluted aquatic systems.
authors.affiliation: Department of Civil and Environmental Engineering, Faculty of Engineering, Tohoku Gakuin University, 1-13-1 Chuo, Tagajo, Miyagi, 985-8537, Japan, goyetibo@unilag.edu.ng.
authors.forename: Ganiyu Oladunjoye
authors.initials: GO
authors.lastname: Oyetibo
authors.forename: Shakirat Titilayo
authors.initials: ST
authors.lastname: Ishola
authors.forename: Wakako
authors.initials: W
authors.lastname: Ikeda-Ohtsubo
authors.forename: Keisuke
authors.initials: K
authors.lastname: Miyauchi
authors.forename: Matthew Olusoji
authors.initials: MO
authors.lastname: Ilori
authors.forename: Ginro
authors.initials: G
authors.lastname: Endo
mesh_terms: D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D063366:Estuaries; D020459:Genes, rRNA; D019015:Geologic Sediments / Q000382:microbiology*; D008628:Mercury / Q000378:metabolism*; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D012331:RNA, Fungal / Q000235:genetics; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D017422:Sequence Analysis, DNA; D014873:Water Pollutants / Q000378:metabolism*; D025062:Yarrowia / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D004271:DNA, Fungal; D004275:DNA, Ribosomal; D012331:RNA, Fungal; D012337:RNA, Ribosomal, 18S; D014873:Water Pollutants; D008628:Mercury