A new group of anti-lipopolysaccharide factors from Marsupenaeus japonicus functions in antibacterial response

• Published in: Developmental and comparative immunology Vol. 48; no. 1; pp. 33 - 42
• Main Authors: Jiang, Hai-Shan, Zhang, Qing, Zhao, Yan-Ran, Jia, Wen-Ming, Zhao, Xiao-Fan, Wang, Jin-Xing
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.01.2015
• Subjects: Amino Acid Sequence; Animals; Anti-Bacterial Agents - pharmacology; Anti-lipopolysaccharide factors; Antimicrobial Cationic Peptides - genetics; Antimicrobial Cationic Peptides - pharmacology; Antimicrobial peptide; Arthropod Proteins - genetics; Arthropod Proteins - pharmacology; Bacterial clearance; Base Sequence; Decapoda; Gills - metabolism; Gram-Negative Bacteria - immunology; Hemocytes - metabolism; Intestines - metabolism; Lipopolysaccharides - immunology; Marsupenaeus japonicus; Molecular Sequence Data; Myocardium - metabolism; Penaeidae - immunology; Penaeidae - metabolism; Peptidoglycan - immunology; Protein Binding; Recombinant Proteins - genetics; Recombinant Proteins - pharmacology; RNA Interference; RNA, Small Interfering; Sequence Alignment; Sequence Analysis, DNA; Shrimp innate immunity; Stomach - metabolism; Vibrio - immunology; Vibrio anguillarum; Vibrio Infections - drug therapy; Vibrio Infections - immunology; Anti-lipopolysaccharide factors; RNA interference; Bacterial clearance; Shrimp innate immunity; Marsupenaeus japonicus; Antimicrobial peptide
• ISSN: 0145-305X; 1879-0089
• DOI: 10.1016/j.dci.2014.09.001

•A new group of ALFs (MjALF-E1 and E2) was identified in Marsupenaeus japonicus.•Both MjALF-E1 and E2 were upregulated by G+ and G− bacterial challenge.•MjALF-E1 and E2 strongly bind to bacterial cell wall components LPS and PGN.•MjALF-E2 exhibited antimicrobial activity against Gram-negative bacteria.•MjALF-E2 promotes the clearance of bacteria in shrimp. Anti-lipopolysaccharide factors (ALFs) are a group of critical effector molecules with a broad spectrum of antimicrobial activities in crustaceans. Four groups of ALFs (A, B, C, and D) have been identified in peneaid shrimp. In the study, we identified a new group of ALFs (designated as MjALF-E) from Marsupenaeus japonicus. This new group (group E) included MjALF-E1 and E2. MjALF-E1 was highly expressed in hemocytes, heart, and intestine, whereas E2 was highly expressed in gills, stomach, and intestine. Expressions of both MjALF-E1 and E2 were upregulated by bacterial challenge. Synthesized LPS-binding domain peptides of MjALF-E1 and E2 strongly bind to bacterial cell wall components lipopolysaccharide (LPS) and peptidoglycan (PGN). The recombinant rMjALF-E2 showed relatively weak binding activity to LPS and PGN. Both synthesized peptides and rMjALF-E2 exhibited antimicrobial activity against Gram-negative bacteria, whereas rMjALF-E2 could promote the clearance of bacteria in vivo. After knockdown of MjALF-E2 and infection with Vibrio anguillarum, shrimp showed high and rapid mortality compared with GFPi shrimp. These results suggest that MjALF-Es serves a protective function against bacterial infection in shrimp.