Learn More
All isolates of Neisseria gonorrhoeae express receptors that bind human transferrin (Tf). Although lactoferrin (Lf) is abundant on mucosa and in purulent exudates, many gonococci do not express an Lf receptor. The naturally occurring Lf receptor deletion mutant FA1090 (LbpB-LbpA-) is infectious, but a Tf receptor mutant of FA1090 is unable to infect male(More)
The pathogenic Neisseria species are capable of utilizing transferrin as their sole source of iron. A neisserial transferrin receptor has been identified and its characteristics defined; however, the biochemical identities of proteins which are required for transferrin receptor function have not yet been determined. We identified two iron-repressible(More)
Pathogenic Neisseria species have been shown to scavenge iron from transferrin (Tf), although the mechanism is not yet fully understood. Two iron-repressible proteins that exhibit Tf-binding activity have been identified. This work describes the cloning and sequencing of tbpB, a 2.1-kb gene in N. gonorrhoeae that encodes Tbp2, an 85-kDa iron-repressible(More)
Iron, an essential nutrient for most microorganisms, is sequestered by the host to decrease the concentration of iron available to bacterial pathogens. Neisseria gonorrhoeae, the causative agent of gonorrhoea, can acquire iron by direct interaction with human iron-binding proteins, including the serum glycoprotein, transferrin. Iron internalization from(More)
Transferrin (TF) and lactoferrin (LF) are probably the major sources of iron (Fe) for Neisseria gonorrhoeae in vivo. We isolated mutants of N. gonorrhoeae FA19 that were unable to grow with Fe bound to either TF (TF-) or LF (LF-) or to both TF and LF ([TF LF]-). The amount of Fe internalized by each of the mutants was reduced to background levels from the(More)
Neisseria gonorrhoeae ordinarily requires both HpuA and HpuB to use hemoglobin (Hb) as a source of iron for growth. Deletion of HpuA resulted in reduced Hb binding and failure of growth on Hb. We identified rare Hb-utilizing colonies (Hb(+)) from an hpuA deletion mutant of FA1090, which fell into two phenotypic classes. One class of the Hb(+) revertants(More)
Piliated gonococci were competent in genetic transformation in all stages of growth in minimal and enriched media, but nonpiliated cells were almost totally incompetent. Uptake of deoxyribonucleic acid into a deoxyribonuclease-insensitive state was observed only in competent piliated cells. Competence was not affected by washing of competent cells or(More)
The ability of 107 Neisseria isolates to compete for iron with human lactoferrin (LF) was examined. Each of 15 meningococci, 53% of 59 selected gonococci, and 24% of 33 commensal Neisseria could use LF-bound iron for growth. Isolates which could not obtain iron from LF were growth inhibited when sufficient LF was added to defined agar medium to bind(More)
Gonococci isolated from localized urogenital infections usually possess one or more protein II (P.II) species in the outer membrane, but the structural and antigenic variation of these proteins among different gonococcal strains has made it difficult to determine if specific proteins of the P.II class are associated with particular sites or types of(More)
Sparling, Philip F. (Communicable Disease Center, Atlanta, Ga.). Genetic transformation of Neisseria gonorrhoeae to streptomycin resistance. J. Bacteriol. 92:1364-1371. 1966.-Eight strains of Neisseria gonorrhoeae were transformed to streptomycin resistance by deoxyribonucleic acid (DNA) extracted from a streptomycin-resistant strain of N. gonorrhoeae. In(More)