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Fisher N, Shetron-Rama L, Herring-Palmer A, Heffernan B, Bergman N, Hanna P.Fisher N, et al.J Bacteriol. 2006 Feb;188(4):1301-9. doi: 10.1128/JB.188.4.1301-1309.2006.J Bacteriol. 2006.PMID: 16452412Free PMC article.