Title
Structural basis for preferential recognition of diaminopimelic acid-type peptidoglycan by a subset of peptidoglycan recognition proteins
UMMS Affiliation
Graduate School of Biomedical Sciences; Department of Medicine, Division of Infectious Diseases and Immunology
Publication Date
2006-01-24
Document Type
Article
Disciplines
Life Sciences | Medicine and Health Sciences
Abstract
Drosophila peptidoglycan recognition protein (PGRP)-LCx and -LCa are receptors that preferentially recognize meso-diaminopimelic acid (DAP)-type peptidoglycan (PGN) present in Gram-negative bacteria over lysine-type PGN of gram-positive bacteria and initiate the IMD signaling pathway, whereas PGRP-LE plays a synergistic role in this process of innate immune defense. How these receptors can distinguish the two types of PGN remains unclear. Here the structure of the PGRP domain of Drosophila PGRP-LE in complex with tracheal cytotoxin (TCT), the monomeric DAP-type PGN, reveals a buried ionic interaction between the unique carboxyl group of DAP and a previously unrecognized arginine residue. This arginine is conserved in the known DAP-type PGN-interacting PGRPs and contributes significantly to the affinity of the protein for the ligand. Unexpectedly, TCT induces infinite head-to-tail dimerization of PGRP-LE, in which the disaccharide moiety, but not the peptide stem, of TCT is positioned at the dimer interface. A sequence comparison suggests that TCT induces heterodimerization of the ectodomains of PGRP-LCx and -LCa in a closely analogous manner to prime the IMD signaling pathway, except that the heterodimer formation is nonperpetuating.
DOI of Published Version
10.1074/jbc.M513030200
Source
J Biol Chem. 2006 Mar 24;281(12):8286-95. Epub 2006 Jan 20. Link to article on publisher's site
Journal/Book/Conference Title
The Journal of biological chemistry
Related Resources
PubMed ID
16428381
Repository Citation
Lim J, Kim M, Kim H, Yano T, Oshima Y, Aggarwal K, Goldman WE, Silverman NS, Kurata S, Oh B. (2006). Structural basis for preferential recognition of diaminopimelic acid-type peptidoglycan by a subset of peptidoglycan recognition proteins. Morningside Graduate School of Biomedical Sciences Student Publications. https://doi.org/10.1074/jbc.M513030200. Retrieved from https://escholarship.umassmed.edu/gsbs_sp/699