Antibiofilm mechanism of a novel milk-derived antimicrobial peptide against Staphylococcus aureus by downregulating agr quorum sensing system

Abstract

Aims Staphylococcus aureus has emerged as a serious threat to food safety owing to biofilm formation. The study aimed to examine the antibiofilm mechanism of a novel milk‐derived antimicrobial peptide BCp12 against it. Methods and results Antibiofilm activity of BCp12 was studied by crystal violet staining, MTT assay, motility, SEM and CLSM. TMT proteome, real‐time PCR and molecular docking in silico were conducted to evaluate the mechanism of BCp12 against S. aureus biofilm. The results showed that BCp12 had significant antibiofilm activity at 1 × MIC and sub‐MIC. BCp12 induced the dispersion of structure of S. aureus biofilm BCp12 inhibited the movement of S. aureus. A total of 703 proteins were downregulated and 334 proteins were upregulated after BCp12 treatment. The proteins (agrA, agrB, agrC and psmβ) of the QS systems were downregulated. Additionally, the expression of the agr‐related genes, agrA, agrB, agrC and psmβ, was downregulated. BCp12 was bound to the receptor proteins agrA and agrC through hydrogen bonds and π–π bonds. Conclusions The results showed the antibiofilm activity of BCp12 and it inhibits the biofilm formation by interfering agr QS system. Significance and Impact of Study BCp12 has the potential to be a novel antibiofilm agent against S. aureus biofilm and used in the food industry.

Nanosized Shikonin-Fe(III) Coordination Material for Synergistic Wound Treatment: An Initial Explorative Study

“…A certain amount of nucleic acids could be leaked during bacterial reproduction in LB culture medium. 33 In other words, the amount of nucleic acid revealed a bacterial reproduction rate. In Figure 3C, it is shown that the proliferation of bacteria was compromised when the Shik-Fe concentration reached 100 μg/mL with an incubation time of 6 h. Since many infectious pathogenic bacteria can form a dense biofilm on the wound, Figures 3D and S12 show the impairment of Shik-Fe on S. aureus biofilm integrity.…”

“…aureus activity of Shik-Fe. A certain amount of nucleic acids could be leaked during bacterial reproduction in LB culture medium . In other words, the amount of nucleic acid revealed a bacterial reproduction rate.…”

A Comprehensive Review of Recent Research into the Effects of Antimicrobial Peptides on Biofilms—January 2020 to September 2023

“…Mutation of the innate defense regulator peptide (IDR-)1018 (1018M) showed activity against MRSA with a 78.9% reduction in biofilm compared to the original peptide and increased binding to the ppGpp stringent response molecule by 27.9% [63]. From non-human sources, the milk-derived AMP BCp12 was shown to bind to accessory gene regulator (agr) QS proteins of S. aureus, potentially useful in the food industry [64]. MPX from wasp venom showed activity against S. aureus and in a skin scratch model was found to reduce S. aureus colonization, thereby resulting in decreased wound size, the promotion of wound healing, and a reduction in inflammation [65].…”

Recent Advances on Antimicrobial Peptides from Milk: Molecular Properties, Mechanisms, and Applications

“…The conjunction between BCp12 and two accessory gene regulator (agr) QS systems' proteins (agrA and agrC) were evaluated by utilizing the Schrodinger Maestro software program, which proposed that BCp12 successfully linked with agrA and agrC through hydrogen bonding, π−π stacking, and hydrophobic interactions. 115 Thereby BCp12 might target agrA and agrC and interfere with the agr QS system, thus avoiding the S. aureus biofilm creation. Likewise, considering Mur ligases have been identified as attractive targets for the exploration of novel antimicrobial drugs and related to PGN synthesis.…”

“…The results showed that three of the 17 AMPs displayed substantial antimicrobial activity and could be developed as highly effective antimicrobial drugs in the years to come. The conjunction between BCp12 and two accessory gene regulator (agr) QS systems’ proteins (agrA and agrC) were evaluated by utilizing the Schrödinger Maestro software program, which proposed that BCp12 successfully linked with agrA and agrC through hydrogen bonding, π–π stacking, and hydrophobic interactions . Thereby BCp12 might target agrA and agrC and interfere with the agr QS system, thus avoiding the S. aureus biofilm creation.…”