Differential expression, molecular cloning, and characterization of porcine beta defensin 114

Abstract

Background β-defensins have attracted considerable research interest because of their roles in protecting hosts from various pathogens. This study was conducted to investigate the expression profiles of the porcine β-defensin 114 ( PBD114 ) in different breeds and in response to infections. Moreover, the function of PBD114 protein was partially investigated. Methods Six Tibetan pigs (TP) and six DLY (Duroc×Landrace×Yorkshire) pigs were slaughtered to explore the expression profiles of PBD114 in different breeds and tissues. For infection models, sixteen DLY pigs were divided into two groups and challenged either with sterile saline or E. coli K88. The recombinant protein PBD114 (rPBD114) was obtained by using a heterologous expression system in E. coli . Results PBD114 gene was highly expressed in tissues such as the intestine, liver, spleen, and thymus. Interestingly, the expression level of PBD114 gene was higher in the TP pigs than in the DLY pigs ( P < 0.05), and was significantly elevated upon E. coli K88 challenge ( P < 0.05). The nucleotide sequences of PBD114 from Tibetan and DLY pigs was identical, and both showed a 210-bp open reading frame encoding a 69-amino acid mature peptide. To explaore the function of PBD114 protein, PBD114 gene was successfully expressed in E. coli Origami B (DE3) and the molecular weight of the rPBD114 was estimated by SDS-PAGE to be 25 kDa. The rPBD114 was purified and mass spectrometry verified the protein as PBD114. Importantly, rPBD114 showed antimicrobial activities against E. coli DH5α and E. coli K88, and the minimal inhibitory concentrations (MICs) were 64 and 128 μg/mL, respectively. Hemolytic and cytotoxicity assays showed that rPBD114 did not affect cell viability under physiological concentrations. Conclusions PBD114 is an infection response gene that is differentially-expressed between different porcine breeds and tissues. The antimicrobial activity of PBD114 protein, against pathogens such as the E. coli K88, suggested that it may serve as a candidate for the substitution of conventionally used antibiotics. Electronic supplementary material The online version of this article (10.1186/s40104-019-0367-0) contains supplementary material, which is available to authorized users.

Expression and functional characterization of a novel antimicrobial peptide: human beta-defensin118

“…and Gram-negative bacteria (E. coli K88 and E. coli DH5α).The MIC for DEFB118 against S. aureus and E. coli K88 was 4 mg/L, which is lower than beta defenses obtained in previous study [38]. These results are also consistent with a previous report on the DEFB118, and both results indicated that the DEFB118 had a broad-spectrum of antibacterial activities [37].…”

“…Recent studies indicated that the β-defensins has multidirectional biological properties, including antiviral, antibacterial, and anti-inflammatory effects [20,21]. For instance, β-defensin 114 was found to show antimicrobial activities against E. coli DH5α and E. coli K88 [22]. While, β-defensin 129 was reported to attenuate intestinal inflammation and epithelial atrophy in rat exposure to bacterial endotoxin [14].…”

Expression and Functional Characterization of a Novel Antimicrobial Peptide: Human Beta-Defensin 118

“…Interestingly, antimicrobial activity assays showed that DEFB118 has significant antimicrobial activity against both the Gram-positive bacteria ( S. aureus and B. subtilis ) and Gram-negative bacteria ( E. coli K88 and E. coli DH5α ). The MIC for DEFB118 against S. aureus and E. coli K88 was 4 mg/L, which is lower than beta defenses obtained in previous study [ 22 ]. These results are also consistent with a previous report on the DEFB118, and both results indicated that the DEFB118 had a broad spectrum of antibacterial activities [ 36 ].…”

“…Recent studies indicated that the β -defensins have multidirectional biological properties, including antiviral, antibacterial, and anti-inflammatory effects [ 20 , 21 ]. For instance, β -defensin 114 was found to show antimicrobial activities against E. coli DH5 α and E. coli K88 [ 22 ], while β -defensin 129 was reported to attenuate intestinal inflammation and epithelial atrophy in rat exposure to bacterial endotoxin [ 14 ]. The human β -defensin 118 (DEFB118) is a novel identified HDP, which is present in the epithelial cells of different ducts and most abundant in the caput epithelium, where it is present in the lumen and located on sperm [ 23 ].…”

Antimicrobial Mechanism of pBD2 against Staphylococcus aureus

“…pBD1 is the first beta defensin discovered in pigs, and it has lower bactericidal activity compared with pBD2, which has strong antibacterial activity against both Gram-negative and Gram-positive bacteria including multi-resistant bacteria [ 6 , 7 , 8 ]. To date, pBD2 has perhaps the strongest antimicrobial activity known among pBDs [ 6 , 9 , 10 ]. Oral administration of pBD2 reduces the inflammatory response in weaned piglets infected with E. coli [ 11 ], and pBD2 attenuates inflammation and mucosal lesions in dextran sodium sulfate-induced colitis in mice [ 12 ].…”