@article{saikaly_hicks_barlaz_reyes_2010, title={Transport Behavior of Surrogate Biological Warfare Agents in a Simulated Landfill: Effect of Leachate Recirculation and Water Infiltration}, volume={44}, ISSN={["1520-5851"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-78449246551&partnerID=MN8TOARS}, DOI={10.1021/es101937a}, abstractNote={An understanding of the transport behavior of biological warfare (BW) agents in landfills is required to evaluate the suitability of landfills for the disposal of building decontamination residue (BDR) following a bioterrorist attack on a building. Surrogate BW agents, Bacillus atrophaeus spores and Serratia marcescens, were spiked into simulated landfill reactors that were filled with synthetic building debris (SBD) and operated for 4 months with leachate recirculation or water infiltration. Quantitative polymerase chain reaction (Q-PCR) was used to monitor surrogate transport. In the leachate recirculation reactors, <10% of spiked surrogates were eluted in leachate over 4 months. In contrast, 45% and 31% of spiked S. marcescens and B. atrophaeus spores were eluted in leachate in the water infiltration reactors. At the termination of the experiment, the number of retained cells and spores in SBD was measured over the depth of the reactor. Less than 3% of the total spiked S. marcescens cells and no B. atrophaeus spores were detected in SBD. These results suggest that significant fractions of the spiked surrogates were strongly attached to SBD.}, number={22}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Saikaly, Pascal E. and Hicks, Kristin and Barlaz, Morton A. and Reyes, Francis L., III}, year={2010}, month={Nov}, pages={8622–8628} }
 @article{saikaly_barlaz_reyes_2007, title={Development of quantitative real-time PCR assays for detection and quantification of surrogate biological warfare agents in building debris and leachate}, volume={73}, ISSN={["1098-5336"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-35448953535&partnerID=MN8TOARS}, DOI={10.1128/AEM.00779-07}, abstractNote={ABSTRACT
          
            Evaluation of the fate and transport of biological warfare (BW) agents in landfills requires the development of specific and sensitive detection assays. The objective of the current study was to develop and validate SYBR green quantitative real-time PCR (Q-PCR) assays for the specific detection and quantification of surrogate BW agents in synthetic building debris (SBD) and leachate.
            Bacillus atrophaeus
            (vegetative cells and spores) and
            Serratia marcescens
            were used as surrogates for
            Bacillus anthracis
            (anthrax) and
            Yersinia pestis
            (plague), respectively. The targets for SYBR green Q-PCR assays were the 16S-23S rRNA intergenic transcribed spacer (ITS) region and
            recA
            gene for
            B. atrophaeus
            and the
            gyrB
            ,
            wzm
            , and
            recA
            genes for
            S. marcescens
            . All assays showed high specificity when tested against 5 ng of closely related
            Bacillus
            and
            Serratia
            nontarget DNA from 21 organisms. Several spore lysis methods that include a combination of one or more of freeze-thaw cycles, chemical lysis, hot detergent treatment, bead beat homogenization, and sonication were evaluated. All methods tested showed similar threshold cycle values. The limit of detection of the developed Q-PCR assays was determined using DNA extracted from a pure bacterial culture and DNA extracted from sterile water, leachate, and SBD samples spiked with increasing quantities of surrogates. The limit of detection for
            B. atrophaeus
            genomic DNA using the ITS and
            B. atrophaeus recA
            Q-PCR assays was 7.5 fg per PCR. The limits of detection of
            S. marcescens
            genomic DNA using the
            gyrB
            ,
            wzm
            , and
            S. marcescens recA
            Q-PCR assays were 7.5 fg, 75 fg, and 7.5 fg per PCR, respectively. Quantification of
            B. atrophaeus
            vegetative cells and spores was linear (
            R
            2
            > 0.98) over a 7-log-unit dynamic range down to 10
            1
            B. atrophaeus
            cells or spores. Quantification of
            S. marcescens
            (
            R
            2
            > 0.98) was linear over a 6-log-unit dynamic range down to 10
            2
            S. marcescens
            cells. The developed Q-PCR assays are highly specific and sensitive and can be used for monitoring the fate and transport of the BW surrogates
            B. atrophaeus
            and
            S. marcescens
            in building debris and leachate.
          }, number={20}, journal={APPLIED AND ENVIRONMENTAL MICROBIOLOGY}, author={Saikaly, Pascal E. and Barlaz, Morton A. and Reyes, Francis L., III}, year={2007}, month={Oct}, pages={6557–6565} }