The HMW2 adhesin of non-typeable Haemophilus influenzae is a human-adapted lectin that mediates high-affinity binding to 2-6 linked N-acetylneuraminic acid glycans. Biochem Biophys Res Commun 2018 Sep 05;503(2):1103-1107
Date
06/27/2018Pubmed ID
29944882Pubmed Central ID
PMC6095747DOI
10.1016/j.bbrc.2018.06.126Scopus ID
2-s2.0-85048968279 (requires institutional sign-in at Scopus site) 17 CitationsAbstract
Non-typeable Haemophilus influenzae (NTHi) is a human-adapted bacterial pathogen, responsible for infections of the human respiratory tract. This pathogen expresses a range of adhesins that mediate binding to host cells. Most NTHi strains can express the related adhesins HMW1 and HMW2. Expression of HMW proteins is phase-variable: changes in the length of simple-sequence repeats located in the encoding genes promoter regions results in changes in expression levels of these adhesins. HMW expression is also controlled by epigenetic regulation. HMW1 has been previously demonstrated to bind α 2-3 sialyl-lactosamine, but affinity of this interaction has not been investigated. The host receptor(s) for HMW2 is currently unknown. We hypothesized that host glycans may act as receptors for HMW2-mediated adherence. We examined the glycan-binding activity of HMW2 using glycan arrays and Surface Plasmon Resonance (SPR). These studies demonstrate that HMW2 binds 2-6 linked N-acetylneuraminic acid with high affinity. HMW2 did not bind glycan structures containing the non-human form of sialic acid, N-glycolylneuraminic acid. Thus, the specificity of HMW1 and HMW2 have complementary lectin activities that may allow NTHi distinct niches in the human host.
Author List
Atack JM, Day CJ, Poole J, Brockman KL, Bakaletz LO, Barenkamp SJ, Jennings MPAuthor
Kenneth Brockman PhD Assistant Professor in the Microbiology and Immunology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Adhesins, BacterialHaemophilus Infections
Haemophilus influenzae
Humans
Lectins
N-Acetylneuraminic Acid
Polysaccharides
Protein Binding