title: Peptidoglycan recognition protein of Chlamys farreri (CfPGRP-S1) mediates immune defenses against bacterial infection.
abstract: Peptidoglycan recognition protein (PGRP) is an essential molecule in innate immunity for both invertebrates and vertebrates, owing to its prominent ability in detecting and eliminating the invading bacteria. Several PGRPs have been identified from mollusk, but their functions and the underlined mechanism are still unclear. In the present study, the mRNA expression profiles, location, and possible functions of PGRP-S1 from Zhikong scallop Chlamys farreri (CfPGRP-S1) were analyzed. The CfPGRP-S1 protein located in the mantle, gill, kidney and gonad of the scallops. Its mRNA expression in hemocytes was up-regulated extremely after PGN stimulation (P<0.01), while moderately after the stimulations of LPS (P<0.01) and β-glucan (P<0.05). The recombinant protein of CfPGRP-S1 (designated as rCfPGRP-S1) exhibited high affinity to PGN and moderate affinity to LPS, but it did not bind β-glucan. Meanwhile, rCfPGRP-S1 also exhibited strong agglutination activity to Gram-positive bacteria Micrococcus luteus and Bacillus subtilis and weak activity to Gram-negative bacteria Escherichia coli. More importantly, rCfPGRP-S1 functioned as a bactericidal amidase to degrade PGN and strongly inhibit the growth of E. coli and Staphyloccocus aureus in the presence of Zn(2+). These results indicated that CfPGRP-S1 could not only serve as a pattern recognition receptor recognizing bacterial PGN and LPS, but also function as a scavenger involved in eliminating response against the invaders.
authors: The Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Rd., Qingdao 266071, Shandong, China.
authors: Jialong
authors: J
authors: Yang
authors: Wan
authors: W
authors: Wang
authors: Xiumei
authors: X
authors: Wei
authors: Limei
authors: L
authors: Qiu
authors: Lingling
authors: L
authors: Wang
authors: Huan
authors: H
authors: Zhang
authors: Linsheng
authors: L
authors: Song
mesh_terms: D000371:Agglutination / Q000276:immunology; D000581:Amidohydrolases / Q000276:immunology; D000818:Animals; D001412:Bacillus subtilis / Q000276:immunology*; D002352:Carrier Proteins / Q000032:analysis / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary; D004926:Escherichia coli / Q000276:immunology*; D006434:Hemocytes / Q000276:immunology; D007113:Immunity, Innate; D008070:Lipopolysaccharides / Q000276:immunology; D016982:Micrococcus luteus / Q000276:immunology*; D049897:Pectinidae / Q000235:genetics / Q000276:immunology* / Q000382:microbiology*; D010457:Peptidoglycan / Q000276:immunology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051192:Receptors, Pattern Recognition / Q000032:analysis / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D011994:Recombinant Proteins / Q000276:immunology / Q000378:metabolism; D012758:Shellfish; D047071:beta-Glucans / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D018076:DNA, Complementary; D008070:Lipopolysaccharides; D010457:Peptidoglycan; D012333:RNA, Messenger; D051192:Receptors, Pattern Recognition; D011994:Recombinant Proteins; D047071:beta-Glucans; C118897:peptidoglycan recognition protein; D000581:Amidohydrolases; C019665:amidase