Protein: Lipopolysaccharide-binding protein (LBP) (P18428)
Organism: Homo sapiens (Human)
Function: Plays a role in the innate immune response. Binds to the lipid A moiety of bacterial lipopolysaccharides (LPS), a glycolipid present in the outer membrane of all Gram-negative bacteria. Acts as an affinity enhancer for CD14, facilitating its association with LPS. Promotes the release of cytokines in response to bacterial lipopolysaccharide.
Subcellular location: Secreted {ECO:0000269|PubMed:2402637, ECO:0000269|PubMed:24120359, ECO:0000269|PubMed:7517398}. Cytoplasmic granule membrane {ECO:0000250|UniProtKB:P17213}. Note=Membrane-associated in polymorphonuclear Leukocytes (PMN) granules. {ECO:0000250|UniProtKB:P17213}.
Sequence: MGALARALPSILLALLLTSTPEALGANPGLVARITDKGLQYAAQEGLLALQSELLRITLPDFTGDLRIPHVGRGRYEFHSLNIHSCELLHSALRPVPGQGLSLSISDSSIRVQGRWKVRKSFFKLQGSFDVSVKGISISVNLLLGSESSGRPTVTASSCSSDIADVEVDMSGDLGWLLNLFHNQIESKFQKVLESRICEMIQKSVSSDLQPYLQTLPVTTEIDSFADIDYSLVEAPRATAQMLEVMFKGEIFHRNHRSPVTLLAAVMSLPEEHNKMVYFAISDYVFNTASLVYHEEGYLNFSITDDMIPPDSNIRLTTKSFRPFVPRLARLYPNMNLELQGSVPSAPLLNFSPGNLSVDPYMEIDAFVLLPSSSKEPVFRLSVATNVSATLTFNTSKITGFLKPGKVKVELKESKVGLFNAELLEALLNYYILNTFYPKFNDKLAEGFPLPLLKRVQLYDLGLQIHKDFLFLGANVQYMRV
InterPro domains: - IPR017943: Bactericidal permeability-increasing protein, alpha/beta domain superfamily (homologous_superfamily) [27-478]
- IPR017942: Lipid-binding serum glycoprotein, N-terminal (domain) [33-256]
- IPR032942: BPI/LBP/Plunc family (family) [4-479]
- IPR001124: Lipid-binding serum glycoprotein, C-terminal (domain) [241-478]
- IPR030675: Lipid binding protein BPI/LBP (family) [7-481]
- IPR017954: Lipid-binding serum glycoprotein, conserved site (conserved_site) [28-60]
Interaction partners: - Monocyte differentiation antigen CD14
- Lymphocyte antigen 96
- Toll-like receptor 4
- Apolipoprotein A-I
- Interleukin-6
- Bactericidal permeability-increasing protein
- C-reactive protein
- Haptoglobin
- Toll-like receptor 2
- Serum amyloid A-1 protein
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0005488 (binding), GO:0097367 (carbohydrate derivative binding), GO:0008289 (lipid binding), GO:0001530 (lipopolysaccharide binding)
Biological Process (BP): GO:0008150 (biological process), GO:0065007 (biological regulation), GO:0050789 (regulation of biological process), GO:0048519 (negative regulation of biological process), GO:0019222 (regulation of metabolic process), GO:0002683 (negative regulation of immune system process), GO:0050794 (regulation of cellular process), GO:0002682 (regulation of immune system process), GO:0051241 (negative regulation of multicellular organismal process), GO:0051239 (regulation of multicellular organismal process), GO:0048523 (negative regulation of cellular process), GO:0009892 (negative regulation of metabolic process), GO:0002695 (negative regulation of leukocyte activation), GO:0050866 (negative regulation of cell activation), GO:0010605 (negative regulation of macromolecule metabolic process), GO:0060255 (regulation of macromolecule metabolic process), GO:0001818 (negative regulation of cytokine production), GO:0002694 (regulation of leukocyte activation), GO:0001817 (regulation of cytokine production), GO:0050865 (regulation of cell activation), GO:1903555 (regulation of tumor necrosis factor superfamily cytokine production), GO:0032677 (regulation of interleukin-8 production), GO:0043030 (regulation of macrophage activation), GO:0032715 (negative regulation of interleukin-6 production), GO:0032675 (regulation of interleukin-6 production), GO:1903556 (negative regulation of tumor necrosis factor superfamily cytokine production), GO:0032717 (negative regulation of interleukin-8 production), GO:0010629 (negative regulation of gene expression), GO:0010468 (regulation of gene expression), GO:0032720 (negative regulation of tumor necrosis factor production), GO:0032680 (regulation of tumor necrosis factor production)
Cellular Component (CC): GO:0005575 (cellular component), GO:0110165 (cellular anatomical entity), GO:0005622 (intracellular anatomical structure), GO:0043226 (organelle), GO:0005615 (extracellular space), GO:0005737 (cytoplasm), GO:0031974 (membrane-enclosed lumen), GO:0012505 (endomembrane system), GO:0005576 (extracellular region), GO:0099080 (supramolecular complex), GO:0036464 (cytoplasmic ribonucleoprotein granule), GO:0030141 (secretory granule), GO:0031410 (cytoplasmic vesicle), GO:0043229 (intracellular organelle), GO:0043230 (extracellular organelle), GO:0043228 (non-membrane-bounded organelle), GO:0005773 (vacuole), GO:0035770 (ribonucleoprotein granule), GO:0043233 (organelle lumen), GO:0070062 (extracellular exosome), GO:0043227 (membrane-bounded organelle), GO:0060205 (cytoplasmic vesicle lumen), GO:0000323 (lytic vacuole), GO:0031983 (vesicle lumen), GO:0099503 (secretory vesicle), GO:0043231 (intracellular membrane-bounded organelle), GO:0034774 (secretory granule lumen), GO:0043232 (intracellular non-membrane-bounded organelle), GO:0065010 (extracellular membrane-bounded organelle), GO:0042581 (specific granule), GO:0010494 (cytoplasmic stress granule), GO:0042582 (azurophil granule), GO:0005775 (vacuolar lumen), GO:0070013 (intracellular organelle lumen), GO:0031982 (vesicle), GO:0005764 (lysosome), GO:0035580 (specific granule lumen), GO:0035578 (azurophil granule lumen), GO:1903561 (extracellular vesicle), GO:0097708 (intracellular vesicle), GO:0005766 (primary lysosome)