Departament de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Diagonal 643. Annex. Floor 0, E-08028, Barcelona, Spain.
Nat Commun. 2023 Jul 18;14(1):4295. doi: 10.1038/s41467-023-40098-z.
Crassvirales (crAss-like phages) are an abundant group of human gut-specific bacteriophages discovered in silico. The use of crAss-like phages as human fecal indicators is proposed but the isolation of only seven cultured strains of crAss-like phages to date has greatly hindered their study. Here, we report the isolation and genetic characterization of 25 new crAss-like phages (termed crAssBcn) infecting Bacteroides intestinalis, belonging to the order Crassvirales, genus Kehishuvirus and, based on their genomic variability, classified into six species. CrAssBcn phage genomes are similar to ΦCrAss001 but show genomic and aminoacidic differences when compared to other crAss-like phages of the same family. CrAssBcn phages are detected in fecal metagenomes around the world at a higher frequency than ΦCrAss001. This study increases the known crAss-like phage isolates and their abundance and heterogeneity open the question of what member of the Crassvirales group should be selected as human fecal marker.
Crassvirales（crAss 样噬菌体）是一类在计算机中发现的大量存在于人类肠道中的噬菌体。目前已经提出将 crAss 样噬菌体用作人类粪便指示剂，但是迄今为止仅分离出七种培养的 crAss 样噬菌体，这极大地阻碍了对其的研究。在这里，我们报告了 25 种新的 crAss 样噬菌体（称为 crAssBcn）的分离和遗传特征，它们感染肠道拟杆菌，属于 Crassvirales 目、Kehishuvirus 属，并且根据其基因组的变异性，分为六个种。CrAssBcn 噬菌体基因组与 ΦCrAss001 相似，但与同一家族的其他 crAss 样噬菌体相比，其基因组和氨基酸存在差异。CrAssBcn 噬菌体在世界各地的粪便宏基因组中检测到的频率高于 ΦCrAss001。这项研究增加了已知的 crAss 样噬菌体分离株及其丰度和异质性，这使得人们开始质疑应该选择该科中的哪个成员作为人类粪便标志物。
