A comparative analysis of lipoprotein transport proteins: LolA and LolB from Vibrio cholerae and LolA from Porphyromonas gingivalis

• Published in: Scientific reports 2023-04, Vol.13 (1), p.6605-6605, Article 6605
• Main Authors: Jaiman, Deepika, Nagampalli, Raghavendra, Persson, Karina
• Format: Article
• Language: English
• Subjects: 631/326; 631/535; Antibiotics; Bacteria; Bacterial Outer Membrane Proteins - metabolism; Carrier Proteins - metabolism; Cell Membrane - metabolism; Comparative analysis; Escherichia coli - metabolism; Escherichia coli Proteins - metabolism; Gram-negative bacteria; Humanities and Social Sciences; Lipoproteins; Lipoproteins - metabolism; Membrane trafficking; multidisciplinary; Periplasm; Periplasmic Binding Proteins - metabolism; Polymyxin B; Porphyromonas gingivalis; Porphyromonas gingivalis - metabolism; Protein transport; Protein Transport - physiology; Science; Science (multidisciplinary); Structure-function relationships; Vibrio cholerae; Vibrio cholerae - metabolism
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-023-33705-y

In Gram-negative bacteria, N-terminal lipidation is a signal for protein trafficking from the inner membrane (IM) to the outer membrane (OM). The IM complex LolCDE extracts lipoproteins from the membrane and moves them to the chaperone LolA. The LolA-lipoprotein complex crosses the periplasm after which the lipoprotein is anchored to the OM. In γ-proteobacteria anchoring is assisted by the receptor LolB, while a corresponding protein has not been identified in other phyla. In light of the low sequence similarity between Lol-systems from different phyla and that they may use different Lol components, it is crucial to compare representative proteins from several species. Here we present a structure–function study of LolA and LolB from two phyla: LolA from Porphyromonas gingivalis (phylum bacteroidota), and LolA and LolB from Vibrio cholerae (phylum proteobacteria). Despite large sequence differences, the LolA structures are very similar, hence structure and function have been conserved throughout evolution. However, an Arg-Pro motif crucial for function in γ-proteobacteria has no counterpart in bacteroidota. We also show that LolA from both phyla bind the antibiotic polymyxin B whereas LolB does not. Collectively, these studies will facilitate the development of antibiotics as they provide awareness of both differences and similarities across phyla.