Infection-induced molecular pattern recognition proteins in larvae of Protaetia brevitarsis seulensis (Coleoptera: Cetoniidae)

We cloned and sequenced full-length peptidoglycan recognition protein (PGRP)-like cDNAs, named PS PGRP-SA(a)-like, PGRP-SA(b)-like, PGRP-SB1-like PGRP-SC-like, from Protaetia brevitarsis seulensis. The amino acid sequences of PGRPs share 32.03-47.93% homology with those PGRP family members in insects mammals, including humans. identified a conserved consensus sequence for amidase activity (His; H-Tyr; Y-His; H-Thr; T-Cys; C) residues binding (PGN), one the major bacterial cell wall components, Asp (D) Phe (F) Lys-type PGN; Gly(G), Trp (W) Arg (R) DAP-type PGN. topological structures PGRP-SA(b)-like PGRP-SC-like proteins are structurally similar to Drosophila melanogaster PGRP-SA, which has three α-helices six β-strands. β-strands located central region helix α1 on back peripheral α2 α3 helices front. also present PGRP-SB1-like, but structure differs that typical PGRP. Significantly increased levels PGRP-SA (a)-like (b)-like mRNA were recorded when Gram-positive bacteria or yeast cells injected into larvae. up-regulated by infection all pathogens; however, expression was 20- 30-fold only shortly after injection Gram-negative bacteria.