Structural characterisation of capsular transporter proteins from Neisseria meningitidis

Neisseria meningitidis (Nm) uses a polysaccharide capsule to protect itself and escape the immune system. Polysaccharide transporters are complexes inserted into bacterial membranes exporting polysaccharides, of which the Nm ABC-transporter-dependent system (CtrA, CtrB, CtrC and CtrD) is one. This thesis presents: the crystallographic structure of CtrC (transmembrane domain of the ABC transporter), the low-resolution TEM structure of CtrB (polysaccharide co-polymerase protein) in detergent, the interactions between CtrB and CtrC and the CtrB/CtrC low-resolution TEM structure in circularised nanodiscs.