title: Characterization of bromate-reducing bacterial isolates and their potential for drinking water treatment.
abstract: The objective of the current study was to isolate and characterize several bromate-reducing bacteria and to examine their potential for bioaugmentation to a drinking water treatment process. Fifteen bromate-reducing bacteria were isolated from three sources. According to 16S rRNA gene sequencing, the bromate-reducing bacteria are phylogenetically diverse, representing the Actinobacteria, Bacteroidetes, Firmicutes, and α-, β-, and γ-Proteobacteria. The broad diversity of bromate-reducing bacteria suggests the widespread capability for microbial bromate reduction. While the cometabolism of bromate via nitrate reductase and (per)chlorate reductase has been postulated, five of our bromate-reducing isolates were unable to reduce nitrate or perchlorate. This suggests that a bromate-specific reduction pathway might exist in some microorganisms. Bioaugmentation of activated carbon filters with eight of the bromate-reducing isolates did not significantly decrease start-up time or increase bromate removal as compared to control filters. To optimize bromate reduction in a biological drinking water treatment process, the predominant mechanism of bromate reduction (i.e., cometabolic or respiratory) needs to be assessed so that appropriate measures can be taken to improve bromate removal.
authors.affiliation: Department of Civil, Architectural, and Environmental Engineering, The University of Texas at Austin, 1 University Station C1786, Austin, TX 78712, USA.
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Davidson
authors.forename: Joanne
authors.initials: J
authors.lastname: Chee-Sanford
authors.forename: Hoi Yi Mandy
authors.initials: HY
authors.lastname: Lai
authors.forename: Chi-hua
authors.initials: CH
authors.lastname: Ho
authors.forename: J Brandon
authors.initials: JB
authors.lastname: Klenzendorf
authors.forename: Mary Jo
authors.initials: MJ
authors.lastname: Kirisits
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D061249:Batch Cell Culture Techniques; D001673:Biodegradation, Environmental; D001959:Bromates / Q000378:metabolism*; D002244:Carbon / Q000032:analysis; D060766:Drinking Water / Q000032:analysis*; D005374:Filtration; D008969:Molecular Sequence Data; D009566:Nitrates / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D010084:Oxidation-Reduction; D010802:Phylogeny; D018508:Water Purification / Q000379:methods*
chemical_list: D001959:Bromates; D060766:Drinking Water; D009566:Nitrates; D009573:Nitrites; D002244:Carbon