Beta-lactamase inhibitor protein

Beta-Lactamase Inhibitor Protein
Beta-Lactamase Inhibitory Protein (BLIP) with α-helices in red, β-sheets in blue, disulphides in yellow. (PDB: 3C7V​)
Identifiers
Symbol	BLIP
Pfam	PF07467
Pfam clan	CL0320
InterPro	IPR009099
SCOP	1s0w
SUPERFAMILY	1s0w
Available protein structures: Pfam structures PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

Beta-Lactamase Inhibitor Proteins (BLIPs) are a family of proteins produced by bacterial species including Streptomyces. BLIP acts as a potent inhibitor of beta-lactamases such as TEM-1, which is the most widespread resistance enzyme to penicillin antibiotics. BLIP binds competitively the surface of TEM-1 and inserting residues into the active site to make direct contacts with catalytic residues. BLIP is able to inhibit a variety of class A beta-lactamases, possibly through flexibility of its two domains. The two tandemly repeated domains of BLIP have an α₂-β₄ structure, the β-hairpin loop from domain 1 inserting into the active site of beta-lactamase.^[1] BLIP shows no sequence similarity with BLIP-II, even though both bind to and inhibit TEM-1.^[2]

Beta-lactamase Inhibitory Protein (white) complexed with beta-lactamase (grey) with key interaction residues highlighted (red). (PDB: 3C7V​)

References

1. Strynadka NC, Jensen SE, Alzari PM, James MN (March 1996). "A potent new mode of beta-lactamase inhibition revealed by the 1.7 A X-ray crystallographic structure of the TEM-1-BLIP complex". Nat. Struct. Biol. 3 (3): 290–7. doi:10.1038/nsb0396-290. PMID 8605632.
2. Lim D, Park HU, De Castro L, Kang SG, Lee HS, Jensen S, Lee KJ, Strynadka NC (October 2001). "Crystal structure and kinetic analysis of beta-lactamase inhibitor protein-II in complex with TEM-1 beta-lactamase". Nat. Struct. Biol. 8 (10): 848–52. doi:10.1038/nsb1001-848. PMID 11573088.

This article incorporates text from the public domain Pfam and InterPro IPR009099