An anti-lipopolysaccharide factor from red swamp crayfish, Procambarus clarkii, exhibited antimicrobial activities in vitro and in vivo.
The anti-lipopolysaccharide factors (ALFs) are a group of effector molecules of innate immunity in arthropods, exhibiting binding and neutralizing activities to lipopolysaccharides. In this study, an ALF cDNA sequence (PcALF1) was identified from red swamp crayfish, Procambarus clarkii. The deduced peptide of PcALF1 was conserved; it manifested the signal peptide and lipopolysaccharide (LPS)-binding domain, especially the two conserved cysteine residues at both ends of the domain. Transcripts of PcALF1 were detected in multiple tissues. Results of quantitative real-time PCR exhibited that the expression level of PcALF1 was induced by virus and Gram-positive and Gram-negative bacteria. Purified recombinant protein of PcALF1 revealed multiple biological activities: it gave all the tested bacteria and fungi a tight binding; it could bind microbial polysaccharides (LPS, LTA, and β-glucan) as well. In vitro, the antimicrobial activity assay was demonstrated as a broad spectrum against Gram-positive and Gram-negative bacteria and a fungus. The rPcALF1 also exhibited a clearance activity on Vibrio anguillarum in a dose-dependent manner in vivo.
The Key Laboratory of Plant Cell Engineering and Germplasm Innovation of Ministry of Education, School of Life Sciences, Shandong University, Jinan, Shandong 250100, China.
Chen
C
Sun
Wen-Teng
WT
Xu
Hong-Wei
HW
Zhang
Li-Ping
LP
Dong
Ting
T
Zhang
Xiao-Fan
XF
Zhao
Jin-Xing
JX
Wang
D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000378:metabolism / Q000494:pharmacology*; D003400:Astacoidea / Q000378:metabolism*; D001483:Base Sequence; D005786:Gene Expression Regulation / Q000276:immunology; D054884:Host-Pathogen Interactions / Q000187:drug effects; D007447:Invertebrate Hormones / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D014733:Vibrio / Q000187:drug effects
D000900:Anti-Bacterial Agents; D007447:Invertebrate Hormones