@article{mbs:/content/journal/micro/10.1099/00221287-140-6-1473, author = "Lee, B Craig", title = "Isolation and characterization of the haeminbinding proteins from Neisseria meningitidis", journal= "Microbiology", year = "1994", volume = "140", number = "6", pages = "1473-1480", doi = "https://doi.org/10.1099/00221287-140-6-1473", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-140-6-1473", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", keywords = "Neisseria meningitidis", keywords = "meningococcal disease", keywords = "haemoglobin", keywords = "iron", keywords = "haemin-binding proteins", abstract = "The mechanism of haem-iron acquisition in Neisseria meningitidis is poorly understood. Using haemin-agarose in a batch affinity chromatography method, two haemin-binding proteins of 97 and 50 kDa were isolated from total membranes derived from Neisseria meningitidis B16B6 grown under iron-deficient but not under iron-replete conditions. No binding proteins were affinity-purified when total membranes underwent limited proteolysis with trypsin, suggesting a haem-protein interaction. When biotinylated human haemoglobin was used as the affinity ligand, proteins of identical molecular mass were isolated. Detection of haemin-binding proteins in a whole cell binding assay demonstrated a surface-exposed location. Competitive binding studies indicated that this haem-protein interaction was specific, because only haemin or human haemoglobin, but not cytochrome c111' protoporphyrin IX, iron-loaded human lactoferrin, iron-loaded human transferrin or Fe(NO3)3, could abrogate binding. The presence of similar haemin-binding proteins in a limited survey of clinical meningococcal strains indicated that the expression of the haemin-binding proteins is not serogroup-specific.", }