Centro Superior de Investigación en Salud Pública (CSISP), Avenida de Cataluña 21, 46020, Valencia, Spain.
Microb Ecol. 2011 Jan;61(1):123-33. doi: 10.1007/s00248-010-9738-y. Epub 2010 Aug 24.
Gut microbiota is the most complex bacterial community in the human body and its study may give important clues to the etiology of different intestinal diseases. Most studies carried out so far have used fecal samples, assuming that these samples have a similar distribution to the communities present throughout the colon. The present study was designed to test this assumption by comparing samples from the rectal mucosa and feces of nine healthy volunteers by sequencing libraries of 16S rRNA genes. At the family taxonomic level, where rarefaction curves indicate that the observed number of taxa is close to the expected one, we observe under different statistical analyses that fecal and mucosal samples cluster separately. The same is found at the level of species considering phylogenetic information. Consequently, it cannot be stated that both samples from a given individual are of similar composition. We believe that the evidence in support of this statement is strong and that it would not change by increasing the number of individuals and/or performing massive sequencing. We do not expect clinicians to stop using feces for research, but we think it is important to caution them on their potential lack of representativeness with respect to the bacterial biofilm on the rectal mucosa.
肠道微生物群是人体内最复杂的细菌群落，对其进行研究可能为不同肠道疾病的病因提供重要线索。迄今为止，大多数研究都使用粪便样本，假设这些样本与整个结肠中存在的群落具有相似的分布。本研究旨在通过对 9 名健康志愿者的直肠黏膜和粪便样本的 16S rRNA 基因测序文库进行比较，验证这一假设。在分类学家族水平上，稀疏曲线表明观察到的分类数量接近预期数量，我们在不同的统计分析中观察到粪便和黏膜样本分别聚类。在考虑系统发育信息的物种水平上也是如此。因此，不能说来自给定个体的两个样本具有相似的组成。我们认为，支持这一说法的证据是强有力的，而且即使增加个体数量和/或进行大规模测序，也不会改变这一说法。我们并不期望临床医生停止使用粪便进行研究，但我们认为，提醒他们注意粪便样本相对于直肠黏膜细菌生物膜的潜在代表性不足是很重要的。
