Fish Shellfish Immunol 2020 Apr 01;99:257-266. doi: 10.1016/j.fsi.2020.02.013.

Identification and characterization of a novel short-type peptidoglycan recognition protein in Apostichopus japonicus.

Abstract
Peptidoglycan recognition proteins (PGRPs) are pattern recognition molecules of the innate immune system via specific recognizing peptidoglycan, a unique component of bacterial cell wall. In the present study, a homologous gene encoding PGRP-S was identified and characterized from Apostichopus japonicus and designated as AjPGRP-S. The open reading frame of AjPGRP-S is 756 bp encoding a polypeptide of 251 amino acids (aa) with a signal peptide (1-24 aa) and a typical PGRP domain (37-178 aa). Phylogenetic analysis and sequence alignment revealed that AjPGRP-S is a member of the PGRP-S family. In healthy sea cucumbers, AjPGRP-S was expressed in all examined tissues with the highest distribution in body wall, muscle, and intestine. In Vibrio splendidus-infected sea cucumbers, AjPGRP-S was remarkably induced in coelomocytes. The recombinant AjPGRP-S (rAjPGRP-S) was shown to possess the highly amidase activity in the presence of Zn2+. Moreover, rAjPGRP-S exhibited agglutination abilities and strong bacteriostatic activities against V. splendidus, V. harveyi, V. parahaemolyticus, Staphylococcus aureus, and Micrococcus luteus. Furthermore, the agglutination ability can be enhanced in the presence of Zn2+. In conclusion, our results suggested that AjPGRP-S serves as a pattern recognition molecule involved in the immune response towards various pathogenic infections.

PubMed ID: 32061713
Article link: Fish Shellfish Immunol


Genes referenced: LOC100887844 LOC115919910 LOC576789 LOC577317