RT Journal Article SR Electronic(1) A1 Bolland, Jeffrey R. A1 Simmons, Warren L. A1 Daubenspeck, James M. A1 Dybvig, KevinYR 2012 T1 Mycoplasma polysaccharide protects against complement JF Microbiology, VO 158 IS 7 SP 1867 OP 1873 DO https://doi.org/10.1099/mic.0.058222-0 PB Microbiology Society, SN 1465-2080, AB 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., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.058222-0