Dataset Information

Burkholderia PglL enzymes are Serine preferring oligosaccharyltransferases which target conserved proteins across the Burkholderia genus.

ABSTRACT: Glycosylation is increasingly recognised as a common protein modification within bacterial proteomes. While great strides have been made in identifying species that contain glycosylation systems, our understanding of the proteins and sites targeted by these systems is far more limited. Within this work we explore the conservation of glycoproteins and glycosylation sites across the pan-Burkholderia glycoproteome. Using a multi-protease glycoproteomic approach, we generate high-confidence glycoproteomes in two widely utilized B. cenocepacia strains, K56-2 and H111. This resource reveals glycosylation occurs exclusively at Serine residues and that glycoproteins/glycosylation sites are highly conserved across B. cenocepacia isolates. This preference for glycosylation at Serine residues is observed across at least 9 Burkholderia glycoproteomes, supporting that Serine is the dominant residue targeted by PglL-mediated glycosylation across the Burkholderia genus. Combined, this work demonstrates that PglL enzymes of the Burkholderia genus are Serine-preferring oligosaccharyltransferases that target conserved and shared protein substrates.

SUBMITTER: Hayes AJ

PROVIDER: S-EPMC8423747 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:We report the results of an investigation into the catalytic role of highly conserved amide (asparagine, glutamine) and OH-containing (serine, tyrosine) residues in several prenyltransferases. We first obtained the X-ray structure of cyclolavandulyl diphosphate synthase containing two molecules of the substrate analog dimethylallyl (S)-thiolodiphosphate (DMASPP). The two molecules have similar diphosphate group orientations to those seen in other ζ-fold (cis- head-to-tail and head-to-middle) prenyltransferases with one diphosphate moiety forming a bidentate chelate with Mg2+ in the so-called S1 site (which is typically the allylic binding site in ζ-fold proteins) while the second diphosphate binds to Mg2+ in the so-called S2 site (which is typically the homoallylic binding site in ζ-fold proteins) via a single P1O1 oxygen. The latter interaction can facilitate direct phosphate-mediated proton abstraction via P1O2, or more likely by an indirect mechanism in which P1O2 stabilizes a basic asparagine species that removes H+, which is then eliminated via an Asn-Ser shuttle. The universal occurrence of Asn-Ser pairs in ζ-fold proteins leads to the idea that the highly conserved amide (Asn, Gln) and OH-containing (Tyr) residues seen in many "head-to-head" prenyltransferases such as squalene and dehydrosqualene synthase might play similar roles, in H+ elimination. Structural, bioinformatics and mutagenesis investigations indeed indicate an important role of these residues in catalysis, with the results of density functional theory calculations showing that Asn bound to Mg2+ can act as a general (imine-like) base, while Gln, Tyr and H2O form a proton channel that is adjacent to the conventional (Asp-rich) "active site". Taken together, our results lead to mechanisms of proton-elimination from carbocations in numerous prenyltransferases in which neutral species (Asn, Gln, Ser, Tyr, H2O) act as proton shuttles, complementing the more familiar roles of acidic groups (in Asp and Glu) that bind to Mg2+, and basic groups (primarily Arg) that bind to diphosphates, in isoprenoid biosynthesis.

Dataset Information

Burkholderia PglL enzymes are Serine preferring oligosaccharyltransferases which target conserved proteins across the Burkholderia genus.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets