Ladewig Lisa, Gloy Leon, Langfeldt Daniela, Pinnow Nicole, Weiland-Bräuer Nancy, Schmitz Ruth A
General Microbiology, Kiel University, Am Botanischen Garten 1-9, 24118 Kiel, Germany.
Institute of Clinical Molecular Biology (IKMB), Kiel University, Am Botanischen Garten 11, 24118 Kiel, Germany.
Microorganisms. 2023 Aug 29;11(9):2184. doi: 10.3390/microorganisms11092184.
The demand for novel antimicrobial compounds is rapidly growing due to the rising appearance of antibiotic resistance in bacteria; accordingly, alternative approaches are urgently needed. Antimicrobial peptides (AMPs) are promising, since they are a naturally occurring part of the innate immune system and display remarkable broad-spectrum activity and high selectivity against various microbes. Marine invertebrates are a primary resource of natural AMPs. Consequently, cDNA expression (EST) libraries from the Cnidarian moon jellyfish and the Ctenophore comb jelly were constructed in . Cell-free size-fractionated cell extracts (<3 kDa) of the two libraries (each with 29,952 clones) were consecutively screened for peptides preventing the biofilm formation of opportunistic pathogens using the crystal violet assay. The 3 kDa fraction of ten individual clones demonstrated promising biofilm-preventing activities against and . Sequencing the respective activity-conferring inserts allowed for the identification of small ORFs encoding peptides (10-22 aa), which were subsequently chemically synthesized to validate their inhibitory potential. Although the peptides are likely artificial products from a random translation of EST inserts, the biofilm-preventing effects against , , , and were verified for five synthetic peptides in a concentration-dependent manner, with peptide BiP_Aa_5 showing the strongest effects. The impact of BiP_Aa_2, BiP_Aa_5, and BiP_Aa_6 on the dynamic biofilm formation of was further validated in microfluidic flow cells, demonstrating a significant reduction in biofilm thickness and volume by BiP_Aa_2 and BiP_Aa_5. Overall, the structural characteristics of the marine invertebrate-derived AMPs, their physicochemical properties, and their promising antibiofilm effects highlight them as attractive candidates for discovering new antimicrobials.
由于细菌中抗生素耐药性的不断出现，对新型抗菌化合物的需求正在迅速增长；因此，迫切需要替代方法。抗菌肽（AMPs）很有前景，因为它们是先天免疫系统的天然组成部分，对各种微生物具有显著的广谱活性和高选择性。海洋无脊椎动物是天然AMPs的主要来源。因此，在[具体年份]构建了来自刺胞动物海月水母和栉水母的cDNA表达（EST）文库。使用结晶紫测定法，对两个文库（每个文库有29,952个克隆）的无细胞大小分级细胞提取物（<3 kDa）连续筛选可防止机会性病原体形成生物膜的肽。十个单独克隆的3 kDa级分对[具体病原体1]和[具体病原体2]表现出有前景的生物膜预防活性。对各自赋予活性的插入片段进行测序，从而鉴定出编码肽（10 - 22个氨基酸）的小开放阅读框，随后对其进行化学合成以验证其抑制潜力。尽管这些肽可能是EST插入片段随机翻译产生的人工产物，但已以浓度依赖性方式验证了五种合成肽对[具体病原体1]、[具体病原体2]、[具体病原体3]和[具体病原体4]的生物膜预防作用，其中肽BiP_Aa_5显示出最强的效果。BiP_Aa_2、BiP_Aa_5和BiP_Aa_6对[具体病原体5]动态生物膜形成的影响在微流控流动池中进一步得到验证，结果表明BiP_Aa_2和BiP_Aa_5使生物膜厚度和体积显著降低。总体而言，海洋无脊椎动物来源的AMPs的结构特征、其理化性质以及其有前景的抗生物膜作用突出表明它们是发现新型抗菌剂的有吸引力的候选物。
