@misc{tjondro_ugonotti_kawahara_chatterjee_loke_chen_soltermann_hinneburg_parker_venkatakrishnan_et al._2020, 
  title={Hyper-Truncated N-Acetyl-β-D-Glucosamine Decorations Augment the Activity and Inhibition Potential of Neutrophil Granule Myeloperoxidase}, 
  DOI={10.1101/2020.07.24.219956}, 
  abstractNote={<jats:p>Myeloperoxidase (MPO), an important glycoprotein in neutrophil-mediated immunity, produces microbicidal hypohalous acids, but the underpinning glycobiology remains elusive. Deep characterisation of neutrophil-derived MPO (nMPO) using advanced mass spectrometry demonstrated that under-processed oligomannosidic-, truncated paucimannosidic- and hyper-truncated N-acetyl-β-D-glucosamine (GlcNAc) core-type asparagine-linked glycans decorate the protein. Occlusion of Asn355 and Asn391 and sterical hindrance of Asn323- and Asn483-glycans located in the MPO dimerisation zone were found to shape the local glycan processing thereby providing a molecular basis for the site-specific nMPO glycosylation. Native mass spectrometry, mass photometry, and glycopeptide profiling revealed extreme molecular complexity of dimeric nMPO arising from heterogeneous glycosylation, oxidation, chlorination and polypeptide truncation variants, and a lower-abundance monomer. Longitudinal profiling of maturing, mature, granule-separated, and pathogen-activated neutrophils demonstrated that MPO is dynamically expressed during granulopoiesis, unevenly distributed across granules and rapidly degranulated, but surprisingly carries uniform glycosylation across conditions. Complete proMPO-to-MPO maturation evidently occur during early/mid-stage granulopoiesis. The conserved Asn355- and Asn391-sequons displayed elevated GlcNAc signatures and higher oxidation and chlorination activity of the secretory vesicle/plasma membrane-resident MPO relative to MPO from other granules. Endoglycosidase H-treated nMPO displaying Asn355-/Asn391-GlcNAcylation recapitulated the activity gain and showed increased thermal stability and enhanced polypeptide flexibility relative to untreated nMPO as measured by activity assays, circular dichroism and molecular dynamics. Endoglycosidase H-treated nMPO also demonstrated an elevated ceruloplasmin-mediated inhibition relative to nMPO. Modelling revealed that hyper-truncated Asn355-glycans positioned in the MPO:ceruloplasmin interface are critical for contact-free inhibition. We report on novel roles of the peculiar MPO glycosylation providing new insight into neutrophil glycobiology.</jats:p>}, 
  publisher={Cold Spring Harbor Laboratory}, 
  author={Tjondro, Harry C and Ugonotti, Julian and Kawahara, Rebeca and Chatterjee, Sayantani and Loke, Ian and Chen, Siyun and Soltermann, Fabian and Hinneburg, Hannes and Parker, Benjamin L and Venkatakrishnan, Vignesh and et al.}, 
  year={2020}, 
  month={Jul}
  }