| abstract |
An isolated and purified outer membrane protein B1, and peptides formed therefrom, of Moraxella catarrhalis are described. A method for the isolation and purification of outer membrane protein B1 from a bacterial strain that produces B1 protein, e.g. Moraxella catarrhalis, comprises growing the bacteria in culture in iron-depleted medium to enhance the expression of the B1 protein, harvesting the bacteria from the culture, extracting from the harvested bacteria a preparation substantially comprising an outer membrane protein preparation, contacting the outer membrane preparation with an affinity matrix containing immobilized transferrin wherein B1 protein binds to the transferrin, and eluting the bound B1 protein from the transferrin. Disclosed are the uses of the B1 protein as an immunogen for vaccine formulations, and as antigens in diagnostic immunoassays. |