Structural and biophysical characterisation of the Neisserial capsular polysaccharide export complex

Many pathogenic bacteria utilise a lipopolysaccharide coating, known as the capsule, to evade host immune responses and aid in disease progression. A membrane protein complex, the capsule transporter complex, mediates the export of the polar lipopolysaccharide capsule components across the hydrophobic cell wall. This work focused on the biophysical and structural characterisation of the capsule transporter proteins that comprise this export machine. The oligomeric state of the proteins and binding affinity between them was established. Crystals of one of the membrane proteins was obtained that diffracted to high resolution. This study sets the foundation for future structure based therapeutic design.