The structure of the polysaccharide of the lipopolysaccharide produced by Taylorella equigenitalis type strain (ATCC 35865).

This study presents a detailed analysis of the polysaccharide component of lipopolysaccharides found in Taylorella equigenitalis, a bacteria causing contagious equine metritis. Researchers identified a specific structure of the antigenic O-polysaccharide that will assist in distinguishing this bacteria from similar, non-pathogenic types.

Introduction to Taylorella equigenitalis

• Taylorella equigenitalis is a Gram-negative bacterium that causes contagious equine metritis (CEM), a venereal disease transmitted among horses.
• Identifying and differentiating this bacterium from similar bacteria and Taylorella species is crucial for controlling CEM infection.

Structure of the Antigenic O-Polysaccharide

• The researchers use Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS) analysis to examine the antigenic O-polysaccharide (O-PS), a component of the lipopolysaccharide (LPS) produced by the type strain T. equigenitalis (ATCC 35865).
• They find that the O-PS is a linear polymer composed of a repeating disaccharide unit with specific components, concluding with a unique 4-O-methylated non-reducing Gulp-NAc3NAcA residue.

Identification as Specific Antigenic Marker

• The unique structure of the O-PS in the T. equigenitalis LPS serves as a specific antigenic marker. This marker can help distinguish this pathogen from a related, non-pathogenic type strain, Taylorella asinigenitalis sp. nov.
• Though T. asinigenitalis sp. nov is phenotypically indistinguishable from T. equigenitalis, it has a different, unrelated LPS O-antigen.

Unusual Core Oligosaccharide of the LPS

• Aside from the antigenic O-PS, this study also reports on an unusual structure found in the core oligosaccharide of the T. equigenitalis LPS.
• The specific details and implications of this unusual structure are not detailed in the abstract, but would be further explored in the full research article.