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Torok VA, Allison GE, Percy NJ, Ophel-Keller K, Hughes RJ.Torok VA, et al.Appl Environ Microbiol. 2011 May;77(10):3380-90. doi: 10.1128/AEM.02300-10. Epub 2011 Mar 25.Appl Environ Microbiol. 2011.PMID: 21441326Free PMC article.