Open AccessHigh antimicrobial activity of lactoferricin‐expressing Bacillus subtilis strains
Author(s) -
Lee BingChang,
Tsai JuiChe,
Hung ChunWei,
Lin ChengYung,
Sheu JinChuan,
Tsai HuaiJen
Publication year - 2022
Publication title -
microbial biotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.287
H-Index - 74
ISSN - 1751-7915
DOI - 10.1111/1751-7915.14026
Subject(s) - microbiology and biotechnology , ampicillin , biology , tetracycline , bacillus subtilis , escherichia coli , streptococcus iniae , bacteria , antibiotics , gene , biochemistry , genetics
Summary The lactoferricin expressed in Bacillus subtilis is relatively low in yield, making it hard to apply in industrial settings. We constructed a six tandem repeat of lactoferricin cDNA driven by promoter PtrnQ. After transformation, two transformants P245 and P263 possessing a stable inheritance of plasmid and high expression of lactoferricin were selected. The bactericidal activities, 1 μl of aliquot of a total 5.5 ml of solution extracted from 5 ml of cultured P245 and P263, were equivalent to the efficacy of 238.25 and 322.7 ng of Ampicillin against Escherichia coli , respectively, and 366.4 and 452.52 ng of Ampicillin against Staphylococcus epidermidis respectively. These extracts were able to kill an Ampicillin‐resistant E. coli strain. The bactericidal activities of P245 and P263 equivalent to the efficacy of Tetracycline against Vibrio parahaemolyticus and V. alginolyticus were also determined. Moreover, the bactericidal activities of P245 and P263 were 168.04 and 249.94 ng of Ampicillin against Edwardsiella tarda , respectively, and 219.7 and 252.43 ng of Tetracycline against Streptococcus iniae respectively. Interestingly, the survival rate of E. tarda ‐infected tilapia fry fed the P263 extract displayed a significantly greater than that of the fry‐fed control strain. Collectively, these B . subtilis transgenic strains are highly promising for use in animal husbandry during a disease outbreak.