Abstract
Phages drive bacterial diversity, profoundly influencing microbial communities, from microbiomes to the drivers of global biogeochemical cycling. Aiming to broaden our understanding of Escherichia coli (MG1655, K-12) phages, we screened 188 Danish wastewater samples and isolated 136 phages. Ninety-two of these have genomic sequences with less than 95% similarity to known phages, while most map to existing genera several represent novel lineages. The isolated phages are highly diverse, estimated to represent roughly one-third of the true diversity of culturable virulent dsDNA Escherichia phages in Danish wastewater, yet almost half (40%) are not represented in metagenomic databases, emphasising the importance of isolating phages to uncover diversity. Seven viral families, Myoviridae, Siphoviridae, Podoviridae, Drexlerviridae, Chaseviridae, Autographviridae, and Microviridae, are represented in the dataset. Their genomes vary drastically in length from 5.3 kb to 170.8 kb, with a guanine and cytosine (GC) content ranging from 35.3% to 60.0%. Hence, even for a model host bacterium, substantial diversity remains to be uncovered. These results expand and underline the range of coliphage diversity and demonstrate how far we are from fully disclosing phage diversity and ecology.
Highlights
Phages are important ecological contributors, renewing organic matter supplies in nutrient cycles and driving bacterial diversity by enabling co-existence of competing bacteria by “Killing the winner”and by serving as genomic reservoirs and transport units [1,2]
We aim to expand our understanding of coliphage diversity, by screening for coliphages targeting a single strain of E. coli
Even though we screened wastewater samples, which is a commonly used source for isolation of coliphages, we identified 136 coliphages of which 92 differed by ≥5% from published phage genomes and some with nucleotide (NT) similarities as low as 29% (Table 1)
Summary
Phages are important ecological contributors, renewing organic matter supplies in nutrient cycles and driving bacterial diversity by enabling co-existence of competing bacteria by “Killing the winner”and by serving as genomic reservoirs and transport units [1,2]. Phages are important ecological contributors, renewing organic matter supplies in nutrient cycles and driving bacterial diversity by enabling co-existence of competing bacteria by “Killing the winner”. Phage genomes are known to contain auxiliary metabolism genes (AMGs), toxins, and virulence factors [3,4,5,6,7]. They can transfer metabolic traits including antibiotic resistance to their hosts and can confer immunity against homologous phages [1]. Still, despite their ecological role, potential as antimicrobials and the fact that they carry a multitude of unknown genes with great potential for biotechnological applications, phages are vastly understudied. The most scrutinized phage host is the Mycobacterium smegmatis, for which the Science Education Alliance Phage Hunters program has isolated more than
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
