9TPM
Structure of LolB from Porphyromonas gingivalis
Summary for 9TPM
| Entry DOI | 10.2210/pdb9tpm/pdb |
| Descriptor | DUF4292 domain-containing protein, SULFATE ION, DI(HYDROXYETHYL)ETHER, ... (7 entities in total) |
| Functional Keywords | lipoprotein transport, insertase, lipoprotein, lipid binding protein |
| Biological source | Porphyromonas gingivalis A7A1-28 |
| Total number of polymer chains | 1 |
| Total formula weight | 32604.72 |
| Authors | Jaiman, D.,Persson, K. (deposition date: 2025-12-18, release date: 2026-02-18, Last modification date: 2026-06-03) |
| Primary citation | Jaiman, D.,Hirohata, M.,Hasegawa, Y.,Persson, K. Identification of a LolB-like protein in Porphyromonas gingivalis reveals selective LolA-LolB pairing. Sci Rep, 16:-, 2026 Cited by PubMed Abstract: The lipoprotein transport (Lol) system is essential for outer membrane biogenesis in Gram-negative bacteria, yet its composition and organization vary markedly across bacterial phyla. While lipoprotein transport via the Lol pathway has been extensively characterized in , its components in the Bacteroidota phylum remain poorly understood. , a major periodontal pathogen has long been thought to lack the outer membrane lipoprotein insertase LolB, leaving the mechanism of lipoprotein insertion unclear. Here, we have identified and characterized a LolB-like protein in (LolB-PG). We determined its crystal structure at 2.1 Å resolution and revealed a conserved LolB fold but with an enlarged and more accessible lipid-binding cleft compared to proteobacterial homologs. Biophysical analyses demonstrate that LolB-PG selectively interacts with the cognate periplasmic chaperone LolA but not with the paralog LolA3, indicating a conserved yet specific LolA–LolB pairing. Deletion of the gene encoding LolBPG did not affect bacterial growth or the assembly, localization, or formation of type-V fimbriae—which are polymerized from lipoproteins— suggesting the existence of alternative lipoprotein trafficking routes in . Together, our findings reveal that Bacteroidota encode a functional LolB-like protein and highlight diversification of lipoprotein transport pathways beyond well-studied γ-proteobacteria. PubMed: 42020509DOI: 10.1038/s41598-026-49975-1 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.1 Å) |
Structure validation
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