Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia.
Commun Biol. 2021 Sep 7;4(1):1045. doi: 10.1038/s42003-021-02588-y.
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.
糖基化越来越被认为是细菌蛋白质组中的一种常见蛋白质修饰。虽然在鉴定含有糖基化系统的物种方面已经取得了很大的进展，但我们对这些系统所针对的蛋白质和位点的理解要有限得多。在这项工作中，我们探讨了泛伯克霍尔德氏菌糖蛋白组中糖蛋白和糖基化位点的保守性。使用多蛋白酶糖蛋白质组学方法，我们在两种广泛使用的 B. cenocepacia 菌株 K56-2 和 H111 中生成了高可信度的糖蛋白组。这一资源表明糖基化仅发生在丝氨酸残基上，并且糖蛋白/糖基化位点在 B. cenocepacia 分离株中高度保守。这种对丝氨酸糖基化的偏好至少存在于 9 个伯克霍尔德氏菌糖蛋白组中，这表明 PglL 介导的糖基化在伯克霍尔德氏菌属中以丝氨酸为主要靶标。综上所述，这项工作表明，伯克霍尔德氏菌属的 PglL 酶是丝氨酸偏好性寡糖基转移酶，其靶向保守和共享的蛋白质底物。
