IDENTIFICATION OF A LACTOFERRIN-BINDING PROTEIN IN PREVOTELLA-NIGRESCENS

A 40-kDa lactoferrin-binding protein was identified in a strain of Pre votella nigrescens isolated from a patient with periodontitis. The pro tein was purified by affinity column chromatography using a Sepharose- lactoferrin column and detergent-solubilized membranes. The N-terminal sequence revealed no apparent similarities with any other sequenced b acterial protein. The native conformation of the 40-kDa protein was a condition to bind either iron-free or iron-saturated lactoferrin. A po ssible function of this Lf-binding protein could be related with an ir on acquisition mechanism in P. nigrescens.