Protoporphyrin IX and heme binding properties of Staphylococcus aureus IsdC

摘要: Staphylococcus aureus is a human pathogen that results in numerous infections hospital settings and recently also the wider community. Its antibiotic resistant forms are causing considerable alarm. A series of surface-anchored proteins have heme uptake transport properties been reported. Through use absorption magnetic circular dichroism spectroscopies mass spectrometry, iron-free, protoporphyrin IX iron-containing, heme-binding characteristics bacterial rIsdC obtained. Mass spectrometry showed following isolation purification, bound predominantly to lesser extent heme, unlike case rIsdA, which binds heme. Magnetic analysis provided further information regarding porphyrin binding because characteristic band envelopes for iron-free iron-containing can be clearly distinguished spectrum rIsdC. Analysis these spectral data minor component exists as high-intermediate spin state ferric when rIsdC, similar high-spin reported rIsdA protein.