UNASSIGNED: Anti-lipopolysaccharide factor is a kind of antimicrobial peptide (AMP) with broad-spectrum activities against bacteria, virus, and fungi in crustacean. Different isoforms of ALFs showed different activities to virus or bacteria. Therefore, discovery of more ALFs will provide new insights into drug development and disease control. Here we reported an ALF gene, EcALF1, isolated from the ridgetail prawn @entity69332 . Its transcripts was mainly detected in hemocytes. Silencing of EcALF1 caused a lesion of hepatopancreas and finally led to death of the prawn. In  vivo bacteria detection to the hepatopancreas showed that the colonies of @entity17464 citrate @entity3645 (TCBS) cultured bacteria in EcALF1-silenced prawn increased dramatically. We identified the dominant bacteria cultured in TCBS and found that @entity12671 and @entity8966 were dominant bacteria which were pathogenic species to prawn. We further synthesized the functional domain, LPS binding domain (LBD) of EcALF1, and its antibacterial and antiviral activities were detected. The synthetic EcLBD1 peptide showed very strong antibacterial activity against @entity7178 and @entity12671 . Pre-incubation of @entity17274 with EcLBD1 peptide reduced the pathogenicity of @entity17274 infection to the prawn. The present data showed the important roles of an ALF gene in modulating the in  vivo bacterial proliferation in @entity69332 and provided new insight in disease control in aquaculture.

Identification and function analysis of an anti-lipopolysaccharide factor from the ridgetail prawn XXXX .

@entity12671 :: ('663', 'Species') :: ['V.  alginolyticus', 'Vibrio alginolyticus'] @entity8966 :: ('670', 'Species') :: ['Vibrio parahaemolyticus'] @entity69332 :: ('392227', 'Species') :: ['E.  carinicauda', 'Exopalaemon carinicauda'] @entity17464 :: ('CHEBI:16094', 'Chemical') :: ['thiosulphate'] @entity3645 :: ('MESH:D001647', 'Chemical') :: ['bile salts'] @entity17274 :: ('92652', 'Species') :: ['WSSV'] @entity7178 :: ('1270', 'Species') :: ['Micrococcus luteus']
@entity69332 :: (392227,Species) :: ['Exopalaemon carinicauda']
