Chris Hadjineophytou

• Wang, Nelson; Anonsen, Jan Haug; Hadjineophytou, Chris; Reinar, William Brynildsen; Børud, Bente; Vik, Åshild & Koomey, John Michael (2020). Allelic polymorphisms in a glycosyltransferase gene shape glycan repertoire in the O-linked protein glycosylation system of Neisseria. Glycobiology.  ISSN 0959-6658. . doi: 10.1093/glycob/cwaa073 Fulltekst i vitenarkiv.
• Hadjineophytou, Chris; Anonsen, Jan Haug; Wang, Nelson; Ma, Kevin; Viburiene, Raimonda; Vik, Åshild; Harrison, Odile B; Maiden, Martin CJ; Grad, Yonatan H. & Koomey, John Michael (2019). Genetic determinants of genus-level glycan diversity in a bacterial protein glycosylation system. PLoS Genetics.  ISSN 1553-7390.  15(12), s 1- 24 . doi: 10.1371/journal.pgen.1008532 Fulltekst i vitenarkiv. Vis sammendrag

  The human pathogens N. gonorrhoeae and N. meningitidis display robust intra- and interstrain glycan diversity associated with their O-linked protein glycosylation (pgl) systems. In an effort to better understand the evolution and function of protein glycosylation operating there, we aimed to determine if other human-restricted, Neisseria species similarly glycosylate proteins and if so, to assess the levels of glycoform diversity. Comparative genomics revealed the conservation of a subset of genes minimally required for O-linked protein glycosylation glycan and established those pgl genes as core genome constituents of the genus. In conjunction with mass spectrometric–based glycan phenotyping, we found that extant glycoform repertoires in N. gonorrhoeae, N. meningitidis and the closely related species N. polysaccharea and N. lactamica reflect the functional replacement of a progenitor glycan biosynthetic pathway. This replacement involved loss of pgl gene components of the primordial pathway coincident with the acquisition of two exogenous glycosyltransferase genes. Critical to this discovery was the identification of a ubiquitous but previously unrecognized glycosyltransferase gene (pglP) that has uniquely undergone parallel but independent pseudogenization in N. gonorrhoeae and N. meningitidis. We suggest that the pseudogenization events are driven by processes of compositional epistasis leading to gene decay. Additionally, we documented instances where inter-species recombination influences pgl gene status and creates discordant genetic interactions due ostensibly to the multi-locus nature of pgl gene networks. In summary, these findings provide a novel perspective on the evolution of protein glycosylation systems and identify phylogenetically informative, genetic differences associated with Neisseria species.

Se alle arbeider i Cristin

• Hadjineophytou, Chris; Anonsen, Jan Haug & Koomey, Michael (2019). Genus-wide assessment of pilus glycosylation in the genus Neisseria.
• Hadjineophytou, Chris; Anonsen, Jan Haug & Koomey, Michael (2018). A genus-wide assessment of neisserial Tfp pilin subunit glycosylation: a systems level approach reveals distribution and governing co-factors.
• Hadjineophytou, Chris & Koomey, Michael (2018). A genus-wide assessment of neisserial Tfp pilin subunit glycosylation: a systems level approach reveals distribution and governing co-factors..

Se alle arbeider i Cristin