英國《自然》雜志網(wǎng)站10月12日刊登研究報告說，一個國際研究小組利用從中世紀死者遺骸中取出的物質(zhì),，測出了曾在中世紀肆虐的黑死病致病菌的基因組，結(jié)果顯示現(xiàn)在所有種類的鼠疫桿菌都與其有關(guān),。
歐洲中世紀所稱的黑死病,，一般認為就是現(xiàn)在的鼠疫,。它由鼠疫桿菌引起，曾在中世紀的歐洲大規(guī)模流行,，使得西歐人口幾近減半,，引起巨大恐慌。
黑死病的一次主要暴發(fā)期是在1347年到1351年間,，當時的倫敦為了處理病死者的尸體,，曾專門建立了幾塊墓地。德國和加拿大等國的研究人員就是從這些墓地里的遺骸中取出相關(guān)物質(zhì),，測出了黑死病致病菌的基因組,。
分析顯示，今天所有的鼠疫桿菌雖然還可劃分出一些不同的菌株,，但它們從基因上看都源于黑死病致病菌,，該病菌可算得上是“瘟疫之祖”。
研究人員認為,，中世紀黑死病致病菌和今天的鼠疫桿菌在基因上的差距并不大，但現(xiàn)在卻少有大規(guī)模鼠疫流行,，這并不是因為病菌本身發(fā)生了多大變化,，而是因為環(huán)境等方面因素發(fā)生了變化。（生物谷 Bioon.com）
doi:10.1038/nature10549
PMC:
PMID:
A draft genome of Yersinia pestis from victims of the Black Death
Kirsten I. Bos; Verena J. Schuenemann; G. Brian Golding; Hernán A. Burbano; Nicholas Waglechner; Brian K. Coombes; Joseph B. McPhee; Sharon N. DeWitte; Matthias Meyer; Sarah Schmedes; James Wood; David J. D. Earn; D. Ann Herring; Peter Bauer; Hendrik N. Poinar; Johannes Krause
Technological advances in DNA recovery and sequencing have drastically expanded the scope of genetic analyses of ancient specimens to the extent that full genomic investigations are now feasible and are quickly becoming standard1. This trend has important implications for infectious disease research because genomic data from ancient microbes may help to elucidate mechanisms of pathogen evolution and adaptation for emerging and re-emerging infections. Here we report a reconstructed ancient genome of Yersinia pestis at 30-fold average coverage from Black Death victims securely dated to episodes of pestilence-associated mortality in London, England, 1348–1350. Genetic architecture and phylogenetic analysis indicate that the ancient organism is ancestral to most extant strains and sits very close to the ancestral node of all Y. pestis commonly associated with human infection. Temporal estimates suggest that the Black Death of 1347–1351 was the main historical event responsible for the introduction and widespread dissemination of the ancestor to all currently circulating Y. pestis strains pathogenic to humans, and further indicates that contemporary Y. pestis epidemics have their origins in the medieval era. Comparisons against modern genomes reveal no unique derived positions in the medieval organism, indicating that the perceived increased virulence of the disease during the Black Death may not have been due to bacterial phenotype. These findings support the notion that factors other than microbial genetics, such as environment, vector dynamics and host susceptibility, should be at the forefront of epidemiological discussions regarding emerging Y. pestis infections.
