Hyper-truncated Asn355-and Asn391-glycans modulate the activity of neutrophil granule myeloperoxidase
Harry C Tjondro, Julian Ugonotti, Rebeca Kawahara, Sayantani Chatterjee, Ian Loke, Siyun Chen, Fabian Soltermann, Hannes Hinneburg, Benjamin L Parker, Vignesh Venkatakrishnan, Regis Dieckmann, Oliver C Grant, Johan Bylund, Alison Rodger, Robert J Woods, Anna Karlsson-Bengtsson, Weston B Struwe, Morten Thaysen-Andersen
JOURNAL OF BIOLOGICAL CHEMISTRY | ELSEVIER | Published : 2021
Myeloperoxidase (MPO) plays essential roles in neutrophil-mediated immunity via the generation of reactive oxidation products. Complex carbohydrates decorate MPO at discrete sites, but their functional relevance remains elusive. To this end, we have characterised the structure-biosynthesis-activity relationship of neutrophil MPO (nMPO). Mass spectrometry demonstrated that nMPO carries both characteristic under-processed and hyper-truncated glycans. Occlusion of the Asn355/Asn391-glycosylation sites and the Asn323-/Asn483-glycans, located in the MPO dimerisation zone, was found to affect the local glycan processing, thereby providing a molecular basis of the site-specific nMPO glycosylation. ..View full abstract
H. C. T. was supported by an Australian Cystic Fibrosis postgraduate studentship award and an international Macquarie University Research Excellence Scholarship (iMQRES). S. Chatterjee was supported by an iMQRES. J. U. was supported by a Macquarie University Research Excellence Scholarship (MQRES). R. K. was supported by an Early Career Fellowship from the Cancer Institute NSW. M. T.-A. was supported by a Macquarie University Safety Net Grant.