Dataset Information

Characterization of the mouse beta defensin 1, Defb1, mutant mouse model.

ABSTRACT: Beta defensins are small cationic antimicrobial peptides present in the respiratory system which have been proposed to be dysfunctional in the environment of the cystic fibrosis lung. Defb1, a murine homologue to the human beta defensins, has also been found to be expressed in the respiratory system and, in order to examine the function of beta defensins in vivo, gene targeting was used to generate Defb1-deficient (Defb1(tm1Hgu)/Defb1(tm1Hgu) [Defb1(-/-)]) mice. The Defb1 synthetic peptide was shown to have a salt-sensitive antimicrobial activity that was stronger against Staphylococcus aureus than against Escherichia coli or Pseudomonas aeruginosa. Defb1(-/-) mice were found, however, to be effective in the clearance of the cystic fibrosis relevant pathogen S. aureus from the airways after nebulization. Although no overt deleterious phenotype was evident in the Defb1(-/-) mice, the number of mutant mice found to harbor bacteria of the Staphylococcus species in the bladder was significantly higher (P = 0.008) than that of controls, suggesting a role for these peptides in resistance to urinary tract infection.

SUBMITTER: Morrison G

PROVIDER: S-EPMC128030 | biostudies-literature | 2002 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Characterization of the mouse beta defensin 1, Defb1, mutant mouse model.

Morrison Gillian G Kilanowski Fiona F Davidson Donald D Dorin Julia J

Infection and immunity 20020601 6

Beta defensins are small cationic antimicrobial peptides present in the respiratory system which have been proposed to be dysfunctional in the environment of the cystic fibrosis lung. Defb1, a murine homologue to the human beta defensins, has also been found to be expressed in the respiratory system and, in order to examine the function of beta defensins in vivo, gene targeting was used to generate Defb1-deficient (Defb1(tm1Hgu)/Defb1(tm1Hgu) [Defb1(-/-)]) mice. The Defb1 synthetic peptide was s ...[more]

PMID: 12010997

Similar Datasets

Project description:Backgroundβ-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.MethodsSix 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.ResultsPBD114 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.ConclusionsPBD114 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.

Dataset Information

Characterization of the mouse beta defensin 1, Defb1, mutant mouse model.

Publications

Characterization of the mouse beta defensin 1, Defb1, mutant mouse model.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets