Suppr超能文献

对巴西东北部人类和犬利什曼原虫分离株全基因组序列的比较分析。

Comparative analyses of whole genome sequences of Leishmania infantum isolates from humans and dogs in northeastern Brazil.

机构信息

Department of Biochemistry, Bioscience Center, Federal University of Rio Grande do Norte, Natal, RN, Rio Grande do Norte, Brazil; Institute of Tropical Medicine of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil.

Institute of Tropical Medicine of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil.

出版信息

Int J Parasitol. 2017 Sep;47(10-11):655-665. doi: 10.1016/j.ijpara.2017.04.004. Epub 2017 Jun 10.

Abstract

The genomic sequences of 20 Leishmania infantum isolates collected in northeastern Brazil were compared with each other and with the available genomic sequences of 29 L. infantum/donovani isolates from Nepal and Turkey. The Brazilian isolates were obtained in the early 1990s or since 2009 from patients with visceral or non-ulcerating cutaneous leishmaniasis, asymptomatic humans, or dogs with visceral leishmaniasis. Two isolates were from the blood and bone marrow of the same visceral leishmaniasis patient. All 20 genomic sequences display 99.95% identity with each other and slightly less identity with a reference L. infantum genome from a Spanish isolate. Despite the high identity, analysis of individual differences among the 32 million base pair genomes showed sufficient variation to allow the isolates to be clustered based on the primary sequence. A major source of variation detected was in chromosome somy, with only four of the 36 chromosomes being predominantly disomic in all 49 isolates examined. In contrast, chromosome 31 was predominantly tetrasomic/pentasomic, consistent with its regions of synteny on two different disomic chromosomes of Trypanosoma brucei. In the Brazilian isolates, evidence for recombination was detected in 27 of the 36 chromosomes. Clustering analyses suggested two populations, in which two of the five older isolates from the 1990s clustered with a majority of recent isolates. Overall the analyses do not suggest individual sequence variants account for differences in clinical outcome or adaptation to different hosts. For the first known time, DNA of isolates from asymptomatic subjects were sequenced. Of interest, these displayed lower diversity than isolates from symptomatic subjects, an observation that deserves further investigation with additional isolates from asymptomatic subjects.

摘要

20 株采自巴西东北部的利什曼原虫(Leishmania infantum)分离株的基因组序列与其他 29 株来自尼泊尔和土耳其的利什曼原虫/杜氏利什曼原虫(L. infantum/donovani)分离株的基因组序列进行了比较。巴西分离株于 20 世纪 90 年代初或 2009 年以来,从内脏利什曼病或非溃疡性皮肤利什曼病患者、无症状感染者或患有内脏利什曼病的犬中获得。其中两个分离株来自同一内脏利什曼病患者的血液和骨髓。所有 20 个基因组序列彼此之间的相似度为 99.95%,与来自西班牙分离株的参考利什曼原虫基因组的相似度略低。尽管相似度很高,但对 3200 万个碱基对基因组之间的个体差异进行分析表明,有足够的变异可以根据主要序列对分离株进行聚类。检测到的一个主要变异来源是染色体倍性,在所有 49 个被检测的分离株中,只有 4 条染色体主要是二倍体。相比之下,染色体 31 主要是四倍体/五倍体,这与其在两种不同二倍体染色体上的区域一致,这些染色体来自于锥虫(Trypanosoma brucei)。在巴西分离株中,在 36 条染色体中的 27 条染色体中检测到重组的证据。聚类分析表明存在两个种群,其中五个 20 世纪 90 年代的较老分离株中的两个与大多数近期分离株聚类。总体而言,这些分析结果表明,个体序列变异并不导致临床结果的差异或对不同宿主的适应性差异。这是首次对无症状受试者的分离株进行测序。有趣的是,这些分离株的多样性低于有症状受试者的分离株,这一观察结果值得进一步研究,以获得更多来自无症状受试者的分离株。

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验