O55 Polysaccharides Are Good Antigen Targets for the Formulation of Vaccines against O55 STEC and Capsulated aEPEC Strains.

The serogroup O55 of is composed of strains whose mechanisms of virulence are different from each other. Since the O55 polysaccharides are present in all O55 strains, and so are the polymers that compose the capsule of O55 atypical enteropathogenic (aEPEC), it was investigated whether anti-O55 antibodies were able to help the innate immune system to eliminate capsulated aEPEC and Shiga toxin-producing (STEC) belonging to the serogroup O55. The results demonstrate that the capsule of EPEC was able to inhibit the deposition of C3b on the bacterial surface and, as a consequence, their lysis by the alternative pathway of the complement system.

The C-Terminal Domain of Zinc Transport Protein AdcA Binds Plasminogen and Factor H In Vitro.

Bacterial acquisition of metals from a host is an essential attribute to facilitate survival and colonization within an infected organism. , a bacterial pathogen of medical importance, has evolved its strategies to acquire multiple metals, including iron, manganese, and zinc. Other important strategies for the colonization and infection of the host have been reported for staphylococci and include the expression of adhesins on the bacterial surface, as well as the acquisition of host plasminogen and complement regulatory proteins.

The multifaceted roles of Leptospira enolase.

A previous study had demonstrated that Leptospira enolase is secreted extracellularly by a yet unknown mechanism and reassociates with the bacterial membrane. Surface-anchored leptospiral enolase displays plasminogen binding activity. In this work, we explored the consequences of this interaction and also assessed whether Leptospira enolase might display additional moonlighting functions by interacting with other host effector proteins.