title: A short-type peptidoglycan recognition protein from tongue sole (Cynoglossus semilaevis) promotes phagocytosis and defense against bacterial infection.
abstract: Peptidoglycan recognition proteins (PGRPs) are members of the innate immune system that interact with bacteria by binding to bacterial peptidoglycan. In this study, we examined the expression and function of a short type of PGRP, CsPGRP-SC2, from tongue sole (Cynoglossus semilaevis). CsPGRP-SC2 contains 164 amino acid residues and shares 54.5%-65.3% overall sequence identities with other teleost PGRPs. CsPGRP-SC2 possesses an amidase domain with a conserved zinc binding site. CsPGRP-SC2 expression occurred in multiple tissues and was upregulated by bacterial and viral infection. Purified recombinant CsPGRP-SC2 (rCsPGRP-SC2) was able to bind and agglutinate Gram-positive bacteria in a Zn(2+)-dependent manner. rCsPGRP-SC2 enhanced the uptake of the bound bacteria by host phagocytes and reduced bacterial dissemination and colonization in host tissues. These results indicate that CsPGRP-SC2 is an innate immune factor that participates in host defense against bacterial infection.
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Qing-lei
authors.initials: QL
authors.lastname: Sun
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, China. Electronic address: lsun@qdio.ac.cn.
authors.forename: Li
authors.initials: L
authors.lastname: Sun
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D004266:DNA Virus Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D005393:Fish Diseases / Q000235:genetics* / Q000276:immunology / Q000382:microbiology / Q000821:virology; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005412:Flatfishes; D007113:Immunity, Innate; D007497:Iridoviridae / Q000502:physiology; D010587:Phagocytosis; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D016415:Sequence Alignment / Q000662:veterinary; D013290:Streptococcal Infections / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D013291:Streptococcus / Q000502:physiology
chemical_list: D002352:Carrier Proteins; D029941:Fish Proteins; C118897:peptidoglycan recognition protein
keywords: Agglutination; Antibacterial effects; Cynoglossus semilaevis; Peptidoglycan recognition protein; Phagocytosis