Last year, I reviewed a PLoS Pathogens paper that found European Black Plague victims from the mid 14th century were infected with more than one clone of Yersinia pestis. While the Y. pestis-specific sequences amplified from several skeletal samples from various countries were evidence of the bacterium as the etiological agent, questions still remained about the virulence of the outbreak. What allowed that ancient strain of Y. pestis to cause such widespread death? Another group of researchers decided to further analyze the causative agent of the Black Plague by enriching for and sequencing one of the extrachromasomal plasmids present in the bacterial genome: the 9.6kb virulence-associated pPCP1 plasmid. Continue reading “Dance Macabre: Will 14th Century Remains Reveal the Pandemic Secrets of the Black Death?”