Microbial Ecology of Perchlorate-Reducing Bacteria that Accumulate High Levels of Chlorate

Master's Thesis

Abstract

Perchlorate (ClO4-) is a harmful oxidant found in drinking water sources throughout the US. Recently, several strains of perchlorate-reducing bacteria (PCRB) that accumulate large amounts of chlorate during perchlorate reduction have been isolated and studied. In this study, it was estimated that these novel perchlorate reducers have similar qmax values to conventional PCRB (8.3mgClO3-/mgX-day and 11.5mgClO4-/mgX-day) and much higher K values (58.3mg/L for chlorate and 192.6mg/L for perchlorate). Based on these kinetic parameters, these novel perchlorate reducers are unlikely to play a significant role in perchlorate reduction at concentrations below 200 mg/L, but may contribute to faster degradation at high concentrations. Analysis of the nucleotide and amino acid sequences of the catalytic subunit of the (per)chlorate reductase enzyme (pcrA) of three high chlorate accumulating isolates were highly similar and distinct from conventional PCRB, suggesting that structural differences in the pcrA enzyme could account for differences in microbial activity.

Attributes

Attribute NameValues
URN
  • etd-09102007-214031

Author Margaret Martin Dudley
Advisor Robert Nerenberg
Contributor Jennifer Dubois, Committee Member
Contributor Jeffrey Talley, Committee Member
Contributor Robert Nerenberg, Committee Chair
Degree Level Master's Thesis
Degree Discipline Civil Engineering and Geological Sciences
Degree Name MSEnvE
Defense Date
  • 2007-07-24

Submission Date 2007-09-10
Country
  • United States of America

Subject
  • biodegradation

  • kinetics

  • (per)chlorate reductase

Publisher
  • University of Notre Dame

Language
  • English

Record Visibility Public
Content License
  • All rights reserved

Departments and Units

Files

Please Note: You may encounter a delay before a download begins. Large or infrequently accessed files can take several minutes to retrieve from our archival storage system.