Mycoplasma polysaccharide protects against complement

Academic Article


  • Although they lack a cell wall, mycoplasmas do possess a glycocalyx. The interactions between the glycocalyx, mycoplasmal surface proteins and host complement were explored using the murine pathogen Mycoplasma pulmonis as a model. It was previously shown that the length of the tandem repeat region of the surface lipoprotein Vsa is associated with susceptibility to complement-mediated killing. Cells producing a long Vsa containing about 40 repeats are resistant to complement, whereas strains that produce a short Vsa of five or fewer repeats are susceptible. We show here that the length of the Vsa protein modulates the affinity of the M. pulmonis EPS-I polysaccharide for the mycoplasma cell surface, with more EPS-I being associated with mycoplasmas producing a short Vsa protein. An examination of mutants that lack EPS-I revealed that planktonic mycoplasmas were highly susceptible to complement killing even when the Vsa protein was long, demonstrating that both EPS-I and Vsa length contribute to resistance. In contrast, the mycoplasmas were resistant to complement even in the absence of EPS-I when the cells were encased in a biofilm. © 2012 SGM.
  • Published In

  • Microbiology  Journal
  • Digital Object Identifier (doi)

    Pubmed Id

  • 22211066
  • Author List

  • Bolland JR; Simmons WL; Daubenspeck JM; Dybvig K
  • Start Page

  • 1867
  • End Page

  • 1873
  • Volume

  • 158
  • Issue

  • 7