1SXR

Drosophila Peptidoglycan Recognition Protein (PGRP)-SA

Summary for 1SXR

• Entry DOI: 10.2210/pdb1sxr/pdb
• Related: 1OHT
• Descriptor: Peptidoglycan recognition protein SA CG11709-PA, SULFATE ION, 1,2-ETHANEDIOL, ... (4 entities in total)
• Functional Keywords: pattern recognition receptor, peptidoglycan, innate immunity, toll pathway, immune system
• Biological source: Drosophila melanogaster (fruit fly)
• Cellular location: Secreted: Q9VYX7
• Total number of polymer chains: 2
• Total formula weight: 41031.94

Authors

Reiser, J.B.,Teyton, L.,Wilson, I.A. (deposition date: 2004-03-31, release date: 2004-06-29, Last modification date: 2024-10-16)

Primary citation

Reiser, J.B.,Teyton, L.,Wilson, I.A.
Crystal structure of the Drosophila peptidoglycan recognition protein (PGRP)-SA at 1.56 A resolution
J.Mol.Biol., 340:909-917, 2004

PubMed Abstract: Peptidoglycan recognition proteins (PGRPs) form a recently discovered protein family, which is conserved from insect to mammals and is implicated in the innate immune system by interacting with/or degrading microbial peptidoglycans (PGNs). Drosophila PGRP-SA is a member of this family of pattern recognition receptors and is involved in insect Toll activation. We report here the crystal structure of PGRP-SA at 1.56 A resolution, which represents the first example of a "recognition" PGRP. Comparison with the catalytic Drosophila PGRP-LB reveals an overall structure conservation with an L-shaped hydrophilic groove that is likely the PGN carbohydrate core binding site, but further suggests some possible functional homology between recognition and catalytic PGRPs. Consistent with sequence analysis, PGRP-SA does not contain the canonical zinc-binding residues found in catalytic PGRPs. However, substitution of the zinc-binding cysteine residue by serine, along with an altered coordinating histidine residue, assembles a constellation of residues that resembles a modified catalytic triad. The serine/histidine juxtaposition to a threonine residue and a carbonyl oxygen atom, along with conservation of the catalytic water molecule found in PGRP-LB, tantalizingly suggests some hydrolytic function for this member of receptor PGRPs.

PubMed: 15223330
DOI: 10.1016/j.jmb.2004.04.077

Experimental method

X-RAY DIFFRACTION (1.56 Å)