Expression pattern, promoter activity and bactericidal property of β-defensin from the mandarin fish Siniperca chuatsi

β-Defensin in Nile tilapia (Oreochromis niloticus): Sequence, tissue expression, and anti-bacterial activity of synthetic peptides

“…In P. olivaceus, medaka (Oryzias latipes), E. coioides, and S. chuatsi, β-defensins show antimicrobial activity against Gramnegative bacteria such as E. coli or A. hydrophila (Guo et al, 2012a;Wang et al, 2012;Nam et al, 2010;Zhao et al, 2009). Additionally, the β-defensins of gilthead seabream (Sparus aurata) and S. chuatsi have antimicrobial activity against Gram-positive bacteria such as Bacillus subtilis and Staphylococcus aureus (Cuesta et al, 2011;Wang et al, 2012), while antiviral activity has been observed in the β-defensins of E. coioides and O. mykiss (Casadei et al, 2009;Guo et al, 2012a). In the present study, we showed that the synthetic Onβ-defensin peptide showed a certain degree of antimicrobial activity against both Gramnegative E. coli DH5α and Gram-positive S. agalactiae GBS.…”

Characterization and expression pattern of a novel β-defensin in common carp (Cyprinus carpio L.): implications for its role in mucosal immunity

“…4), similarly to the results for zebrafish, 12) rainbow trout, 16) gilthead seabream, 18) orange-spotted grouper, 19) and mandarin fish. 20) Among these tissues, the common carp β-defensin 3 mRNA was mainly expressed in the spleen, which coincided with omBD-4 in the rainbow trout and ScBD in the mandarin fish. Additionally, there was high expression of β-defensin in the gills of the common carp (β-defensin 3), rainbow trout (omDB-3 and -4), orange-spotted grouper, and gilthead seabream.…”

“…12,15) In healthy fish, some of these β-defensins are expressed in a wide range of mucosal and systemic tissues, including the gills, gonad, gut, peritoneal leucocytes, kidney, liver, muscle, skin, and spleen. 12,16,[18][19][20] In contrast, some β-defensins in other species have been detected only in one or two tissues. 12,15,21) After challenge with bacteria and with bacterial DNA, the gene expression of β-defensin was upregulated in some of these tissues, [16][17][18] suggesting the important role of this gene in the immune responses of fish.…”

“…14) In fish, β-defensins have recently been identified in many species, including zebrafish (Danio rerio) zfDB-1, -2, and -3; fugu (Takifugu rubripes) fuDB-1; tetraodron (Tetraodon nigroviridis) tnDB-1 and -2; 12) rainbow trout (Oncorhynchus mykiss) omDB-1 to -4; 15,16) olive flounder (Paralichthys olivaceus) fBDI-1 to -5; 17) gilthead seabream (Sparus aurata) saBD; 18) orange-spotted grouper (Epinephelus coioides) EcDefensin; 19) mandarin fish (Siniperca chuatsi) ScBD; 20) and the common carp (Cyprinus carpio L.) BD1 and BD2. 21) Based on homology comparison and phylogenetic analysis, the multiple defensin-like genes discovered in fish have been classified into two subgroups, the BD-1 group, and another group containing BD-2 and BD-3.…”

“…12,15,21) After challenge with bacteria and with bacterial DNA, the gene expression of β-defensin was upregulated in some of these tissues, [16][17][18] suggesting the important role of this gene in the immune responses of fish. Moreover, the recombinant β-defensin peptides showed strong antimicrobial activity against gram-negative bacteria E. coli, V. anguillarum, and A. hydrophila, [17][18][19][20] grampositive bacteria B. subtilis and S. saureus, 18,20) and certain viruses. 15,19) The immune system of vertebrates is composed of two subdivisions, the innate immune system and the adaptive immune system, and innate immunity provides the first line of defense against invading pathogens.…”