How small are bacteria? New research indicates that they can be far smaller than we originally thought! The standard method of collecting environmental bacteria is by using a 0.2 micron filter (see our filtering blog post). We’ve noticed with our samples that even water passed through a 0.2 micron filter still has some bacteria in it. These researchers have further investigated the bacteria that can pass through a filter (called ultra-small bacteria) and have found some cool results:
– Most of the ultra-small bacteria belong to candidate phyla – groups of bacteria with no cultured representatives
– The ultra-small bacteria appear to be packed with DNA
– Ultra-small bacteria appear to have pili, protein structures that extend out from the cell membrane to contact other cells. Are they using these pili to get nutrients they can’t produce themselves?
Check out the full paper below for some very cool pictures of ultra-small bacteria!