title: Isolation and characterization of Acidithiobacillus caldus from a sulfur-oxidizing bacterial biosensor and its role in detection of toxic chemicals.
abstract: A novel toxicity detection methodology based on sulfur-oxidizing bacteria (SOB) has been developed for the rapid and reliable detection of toxic chemicals in water. The methodology exploits the ability of SOB to oxidize sulfur particles in the presence of oxygen to produce sulfuric acid. The reaction results in an increase in electrical conductivity (EC) and a decrease in pH. The assay is based on the inhibition of SOB in the presence of toxic chemicals by measuring changes in EC and pH. We found that SOB biosensor can detect toxic chemicals, such as heavy metals and CN-, in the 5-2000ppb range. One bacterium was isolated from an SOB biosensor and the 16S rRNA gene of the bacterial strain has 99% and 96% sequence similarity to Acidithiobacillus sp. ORCS6 and Acidithiobacillus caldus DSM 8584, respectively. The isolate was identified as A. caldus SMK. The SOB biosensor is ideally suited for monitoring toxic chemicals in water having the advantages of high sensitivity and quick detection.
authors.affiliation: Department of Biological Environment, Kangwon National University, Chuncheon, Kangwon-do, Republic of Korea.
authors.forename: Sedky H A
authors.initials: SH
authors.lastname: Hassan
authors.forename: Steven W
authors.initials: SW
authors.lastname: Van Ginkel
authors.forename: Sung-Min
authors.initials: SM
authors.lastname: Kim
authors.forename: Sung-Hwan
authors.initials: SH
authors.lastname: Yoon
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Joo
authors.forename: Beom-Soo
authors.initials: BS
authors.lastname: Shin
authors.forename: Byong-Hun
authors.initials: BH
authors.lastname: Jeon
authors.forename: Wookeun
authors.initials: W
authors.lastname: Bae
authors.forename: Sang-Eun
authors.initials: SE
authors.lastname: Oh
mesh_terms: D042763:Acidithiobacillus / Q000145:classification / Q000302:isolation & purification* / Q000378:metabolism*; D001419:Bacteria; D015374:Biosensing Techniques / Q000379:methods*; D001711:Biotransformation; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D004553:Electric Conductivity; D006863:Hydrogen-Ion Concentration; D019216:Metals, Heavy / Q000032:analysis*; D010084:Oxidation-Reduction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D013455:Sulfur / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014877:Water Pollution, Chemical
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D019216:Metals, Heavy; D012336:RNA, Ribosomal, 16S; D014874:Water Pollutants, Chemical; D013455:Sulfur