Related Experiment Video
Updated: Jan 26, 2026

A Practical Guide to Phylogenetics for Nonexperts
Published on: February 5, 2014
Diversion and phylogenetic relatedness of filterable bacteria from Norwegian tap and bottled waters
Colin Charnock1, Ralf Xue Hagen1, Theresa Ngoc-Thu Nguyen1
1Department of Life Sciences and Health, Oslo Metropolitan University, NO-0130, Oslo, Norway
Abstract:
Numerous articles have documented the existence of filterable bacteria. Where filtration is the chosen method of sterilization for medicinal or media components, these bacteria will by definition render products non-sterile. They may further represent a health hazard to the end user. A wide-range of bacterial genera were found in bottled and tap water filtrates from 0.2 μm filters, including genera housing opportunistic pathogens (e.g. Methylobacterium) and endospore formers (Paenibacillus). Two municipal tap water isolates were only distantly related to named species. One of these grew on agar, and could potentially provide hitherto unharvested useful biological products. The other grew only in water, and failed to produce colonies on media targeting either heterotrophs or autotrophs. The present study is one of very few looking at filterable bacteria in bottled waters intended for human consumption and the first identifying the filterable portion. It extends the range of known habitats of filterable bacteria and provides data on two new or novel species.
Related Concept Videos
Phylogenetic Trees
Passive Filters
Low-Pass Filters
Low-pass filters are designed to transmit signals with frequencies lower than the cutoff frequency, ωc, and attenuate those above it. The cutoff...
Active Filters
Diversity of Archaea I
Diversity of Archaea II
Diversity of Protists I

