bactericidal permeability-increasing protein; BPI; CAP 57 (BPI)

Function: - cytotoxic action of BPI is limited to many species of Gram-negative bacteria specificity may be explained by a strong affinity of the very basic N-terminal half for the negatively charged lipopolysaccharides that are unique to the Gram-negative bacterial outer envelope - has antibacterial activity against the P. aeruginosa, this activity is inhibited by LPS from P. aeruginosa - during phagocytosis & degranulation, proteases may be released & activated & cleave BPI at the junction of the N- & C-terminal portions of the molecule, providing controlled release of the N-terminal antibacterial fragment when bacteria are ingested Structure: - monomer. homodimer; disulfide-linked - the N-terminal region may be exposed to the interior of the granule, whereas the C-terminal portion may be embedded in the membrane - belongs to the BPI/LBP/plunc superfamily, BPI/LBP family - contains 2 LRR repeats (leucine-rich repeats) Compartment: - secreted - cytoplasmic granule membrane - membrane-associated in polymorphonuclear leukocyte (PMN) granules Expression: restricted to cells of the myeloid series

General

glycoprotein leucine-rich repeat-containing protein (LRRC) membrane protein secreted protein

Properties

SIZE: entity length = 487 aa MW = 54 kD COMPARTMENT: cytoplasm cell nucleus MOTIF: signal sequence {1-31} leucine-rich repeat SITE: 86-111 MOTIF: leucine residue (SEVERAL) cysteine residue {C166} MODIFICATION: cysteine residue {C206} cysteine residue {C206} MODIFICATION: cysteine residue {C166} Cleavage sites for elastase {240-245} N-glycosylation site {N380} leucine-rich repeat SITE: 412-434 MOTIF: leucine residue (SEVERAL)

Database Correlations

OMIM 109195 UniProt P17213 PFAM correlations Entrez Gene 671 Kegg hsa:671

References

UniProt :accession P17213