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Covalent bonding of heme to protein prevents heme capture by nontypeable Haemophilus influenzae.

ABSTRACT: Nontypeable Haemophilus influenzae (NTHi) are Gram-negative pathogens that contribute to a variety of diseases, including acute otitis media and chronic obstructive pulmonary disease. As NTHi have an absolute requirement for heme during aerobic growth, these bacteria have to scavenge heme from their human hosts. These heme sources can range from free heme to heme bound to proteins, such as hemoglobin. To test the impact of heme structural factors on heme acquisition by NTHi, we prepared a series of heme sources that systematically vary in heme exposure and covalent binding of heme to peptide/protein and tested the ability of NTHi to use these sources to support growth. Results from this study suggest that NTHi can utilize protein-associated heme only if it is noncovalently attached to the protein.

SUBMITTER: Sgheiza V

PROVIDER: S-EPMC5666386 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Covalent bonding of heme to protein prevents heme capture by nontypeable Haemophilus influenzae.

Sgheiza Valerie V Novick Bethany B Stanton Sarah S Pierce Jeanetta J Kalmeta Breanne B Holmquist Melody Frink MF Grimaldi Kyle K Bren Kara L KL Michel Lea Vacca LV

FEBS open bio 20171012 11

Nontypeable Haemophilus influenzae (NTHi) are Gram-negative pathogens that contribute to a variety of diseases, including acute otitis media and chronic obstructive pulmonary disease. As NTHi have an absolute requirement for heme during aerobic growth, these bacteria have to scavenge heme from their human hosts. These heme sources can range from free heme to heme bound to proteins, such as hemoglobin. To test the impact of heme structural factors on heme acquisition by NTHi, we prepared a ...[more]

PMID: 29123985

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