title: Bioaccumulation of Vanadium by Vanadium-Resistant Bacteria Isolated from the Intestine of Ascidia sydneiensis samea.
abstract: Isolation of naturally occurring bacterial strains from metal-rich environments has gained popularity due to the growing need for bioremediation technologies. In this study, we found that the vanadium concentration in the intestine of the vanadium-rich ascidian Ascidia sydneiensis samea could reach 0.67 mM, and thus, we isolated vanadium-resistant bacteria from the intestinal contents and determined the ability of each bacterial strain to accumulate vanadium and other heavy metals. Nine strains of vanadium-resistant bacteria were successfully isolated, of which two strains, V-RA-4 and S-RA-6, accumulated vanadium at a higher rate than did the other strains. The maximum vanadium absorption by these bacteria was achieved at pH 3, and intracellular accumulation was the predominant mechanism. Each strain strongly accumulated copper and cobalt ions, but accumulation of nickel and molybdate ions was relatively low. These bacterial strains can be applied to protocols for bioremediation of vanadium and heavy metal toxicity.
authors.affiliation: Molecular Physiology Laboratory, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Japan.|Biology Department, Science and Technology Faculty, State Islamic University of Malang, Malang, Indonesia.
authors.lastname: Romaidi
authors.affiliation: Molecular Physiology Laboratory, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Japan. ueki@hiroshima-u.ac.jp.|Marine Biological Laboratory, Graduate School of Science, Hiroshima University, Onomichi, Japan. ueki@hiroshima-u.ac.jp.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Ueki
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000818:Animals; D001419:Bacteria / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D001673:Biodegradation, Environmental; D003035:Cobalt / Q000378:metabolism; D003300:Copper / Q000378:metabolism; D000069196:Gastrointestinal Microbiome / Q000235:genetics*; D006863:Hydrogen-Ion Concentration; D007422:Intestines / Q000382:microbiology; D017136:Ion Transport; D007700:Kinetics; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D017422:Sequence Analysis, DNA; D014561:Urochordata / Q000382:microbiology*; D014639:Vanadium / Q000378:metabolism*
chemical_list: D012336:RNA, Ribosomal, 16S; D014639:Vanadium; D003035:Cobalt; D003300:Copper
keywords: Ascidian; Bioaccumulation; Heavy metals; Intestine; Vanadium-resistant bacteria