Gram-negative bacteria protect themselves with an outermost layer containing lipopolysaccharide (LPS). O-antigen-specific bacteriophages use tailspike proteins (TSP) to recognize and cleave the O-polysaccharide part of LPS. However. O-antigen composition and structure can be highly variable depending on the environmental conditions. https://www.mariameetsanna.com/product-category/taper-2000-adjustble-cut-clipper/