Department of Biology, University of Puerto Rico, Río Piedras Campus, 17 Avenido, Universidad Suite 1701, San Juan, Puerto Rico 00925-2537.
Molecular Sciences Research Center, University of Puerto Rico, 1390 Ponce De Leon Avenido, Suite 2, San Juan Puerto Rico 00931-3346.
ACS Appl Mater Interfaces. 2020 Oct 14;12(41):46991-47001. doi: 10.1021/acsami.0c13492. Epub 2020 Sep 30.
Many pathogens, such as and bacteria can easily attach to surfaces and form stable biofilms. The formation of such biofilms in surfaces presents a problem in environmental, biomedical, and industrial processes, among many others. Aiming to provide a plausible solution to this issue, the anionic and hydrophobic peptide Maximin H5 C-terminally deaminated isoform (MH5C) has been modified with a cysteine in the C-terminal (MH5C-Cys) and coupled to polyethylene glycol (PEG) polymers of varying sizes (i.e., 2 kDa and 5 kDa) to serve as a surface protective coating. Briefly, the MH5C-Cys was bioconjugated to PEG and purified by size exclusion chromatography while the reaction was confirmed via SDS-PAGE and MALDI ToF. Moreover, the preventive antimicrobial activity of the MH5C-Cys-PEG conjugates was performed via the growth curves method, showing inhibition of bacterial growth after 24 h. The efficacy of these peptide-polymer conjugates was extensively characterized via scanning electron microscopy (SEM), minimum inhibition concentration (MIC), minimum biofilm inhibition concentration (MBIC), and minimum biofilm eradication concentration (MBEC) assays to evaluate their ability to eradicate and prevent the biofilms. Interestingly, this work demonstrated a critical PEG polymer weight of 5 kDa as ideal when coupled to the peptide to achieve inhibition and eradication of the biofilm formation in both bacteria strains. According to the MICs (40 μM) and MBICs (300 μM), we can conclude that this conjugate (MH5C-Cys-5 kDa) has an action that prevents/inhibits the formation of biofilms and the eradication of biofilms (MBEC 500 μM). In contrast, the MH5C-Cys peptide with PEG polymer of 2 kDa did not show inhibition or eradication of the biofilms.
许多病原体，如 和 细菌，很容易附着在表面上并形成稳定的生物膜。这种生物膜在表面上的形成在环境、生物医学和工业过程等方面都存在问题。为了解决这个问题，我们对带正电荷和疏水性的肽 Maximin H5 C 端脱氨酶同型物（MH5C）进行了修饰，在 C 端加上一个半胱氨酸（MH5C-Cys），并与不同大小的聚乙二醇（PEG）聚合物（即 2 kDa 和 5 kDa）偶联，作为表面保护涂层。简而言之，MH5C-Cys 通过生物偶联与 PEG 连接，并通过凝胶排阻色谱法进行纯化，同时通过 SDS-PAGE 和 MALDI ToF 进行确认。此外，通过生长曲线法研究了 MH5C-Cys-PEG 缀合物的预防性抗菌活性，结果表明在 24 小时后抑制了细菌生长。通过扫描电子显微镜（SEM）、最小抑制浓度（MIC）、最小生物膜抑制浓度（MBIC）和最小生物膜消除浓度（MBEC）评估，广泛研究了这些肽-聚合物缀合物的功效，以评估其消除和预防生物膜形成的能力。有趣的是，这项工作表明，当与肽偶联时，理想的 PEG 聚合物重量为 5 kDa，以实现对两种细菌菌株生物膜形成的抑制和消除。根据 MIC（40 μM）和 MBIC（300 μM），我们可以得出结论，该缀合物（MH5C-Cys-5 kDa）具有预防/抑制生物膜形成和消除生物膜（MBEC 500 μM）的作用。相比之下，带有 2 kDa PEG 聚合物的 MH5C-Cys 肽没有显示出对生物膜的抑制或消除作用。
