在古代DNA中广泛出现的肉毒素和破伤风神经毒素基因
Shyan Mascarenhas1, Harold P Hodgins1, Andrew C Doxey2
1Department of Biology and Waterloo Centre for Microbial Research, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada.
概括
古代DNA分析揭示了密闭性神经毒素基因的频繁发生,包括神经毒素 (TeNT) 和各种肉毒神经毒素 (BoNT),在人类和动物遗骸中. 这些发现表明,病原性克洛斯特里迪亚和腐烂的有机物之间存在着强烈的生态联系.
科学领域:
- 古遗传学是古遗传学的一部分.
- 微生物遗传学 微生物遗传学
- 考古学科学 考古学科学
背景情况:
- 来自考古遗址的古代DNA (aDNA) 提供了对过去人类遗传多样性和相关的微生物DNA (包括病原体) 的洞察.
- 之前的研究已经在DNA中确定了Clostridium tetani和神经毒素 (TeNT) 基因,但其他毒素基因的患病率仍然不清楚.
研究的目的:
- 在古老的DNA数据集中进行大规模调查,研究密闭性神经毒素基因的存在和多样性.
- 确定各种神经毒素基因在古代标本中保存和检测到的程度.
主要方法:
- 分析了来自不同人类和非人类来源的6435个古老DNA (aDNA) 测序数据集.
- 通过序列匹配,系统地搜索49种闭膜神经毒素类型/亚型和3种额外的毒素.
主要成果:
- 105个aDNA数据集 (1.6%) 产生了与神经毒素基因的显著匹配.
- 结核神经毒素 (TeNT) 基因是最常见的 (50 个数据集),以及各种肉毒神经毒素 (BoNT/C,D,B,E) 和与肠球菌相关的BoNT/En.
- 在人类和动物遗骸 (马,熊,黑猩猩,大猩猩,狗) 中发现了毒素基因,埃及木乃伊显示出最高的多样性;确定的序列与现代毒素非常相似.
结论:
- 密闭性神经毒素基因在DNA中经常被检测到,这表明它们在古代环境中普遍存在.
- 这些基因的流行很可能源于致病性克洛斯特里迪亚与腐烂的有机物质和潜在的死后殖民的生态联系.
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