Dimitrova Dilyana, Nemska Veronica, Iliev Ivan, Petrin Stoyko, Georgieva Nelly, Danalev Dancho
Biotechnology Department, University of Chemical Technology and Metallurgy, 8 Kliment Ohridski Blvd., 1797 Sofia, Bulgaria.
Institute of Experimental Morphology, Pathology and Anthropology with Museum, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 25, 1113 Sofia, Bulgaria.
Pharmaceutics. 2025 Mar 21;17(4):396. doi: 10.3390/pharmaceutics17040396.
: With growing antimicrobial resistance, the overuse of antibiotics, and stagnation in the discovery of new antibiotics, a novel alternative is required to overcome hard-to-treat infections. Antimicrobial peptides (AMPs) show great potential as a possible alternative to standard chemotherapeutics. Temporins are a group of AMPs that have been under the spotlight in numerous studies. Herein, we report the design and synthesis of Temporin A modified in position 1, where the proteinogenic amino acid Phe is replaced by Tyr or fluorinated Phe. In addition, in other analogues, in position 10, the Ser residue is replaced by Tyr or Thr. The aim of all modifications in the primary structure of the native Temporin A is to study the influence of the changes made on the antibacterial properties, antiproliferative activity, and hydrolytic stability of the newly synthesized molecules. : The Fmoc/OBu SPPS strategy was employed for the synthesis of the novel-designed analogues. The antibacterial activity was evaluated with both disk diffusion and broth microdilution methods. The BALB 3T3 NRU test and MTT dye reduction assay were used to determine safety and antiproliferative activity. : The investigated analogues have low toxicity and are photosafe. The greatest selectivity was shown by DTTyr10 towards MCF-7 cells. DT4F, containing fluorinated Phe in position 1, was the most effective antibacterial agent among the new compounds. The incorporation of Thr in position 10, in comparison with the natural Ser residue, led to an increase in the antiproliferative effect of the new peptide. : The obtained structure-activity relationship data show that the most promising compound in the tested series is FLPLIGRVL--GILNH, where the Ser residue in position 10 is replaced by a more hydrophobic OH-containing Tyr residue. The analogue containing fluorinated Phe in position 1, DT4F, has the highest antiproliferative effect against both tested tumor cell lines, combined with good antibacterial properties at the lowest MIC (80 µg/mL), but it is more cyto- and phototoxic than the parent DTA molecule and is not stable at pH 9 for a 24 h period.
随着抗菌耐药性的增加、抗生素的过度使用以及新抗生素发现的停滞，需要一种新的替代方法来克服难以治疗的感染。抗菌肽（AMPs）作为标准化疗药物的一种可能替代物显示出巨大潜力。天蚕抗菌肽是在众多研究中备受关注的一类抗菌肽。在此，我们报告了在第1位进行修饰的天蚕抗菌肽A的设计与合成，其中蛋白质原性氨基酸苯丙氨酸（Phe）被酪氨酸（Tyr）或氟化苯丙氨酸取代。此外，在其他类似物中，第10位的丝氨酸（Ser）残基被酪氨酸或苏氨酸取代。对天然天蚕抗菌肽A一级结构进行所有修饰的目的是研究这些变化对新合成分子的抗菌特性、抗增殖活性和水解稳定性的影响。
采用Fmoc/OBu固相肽合成策略合成新设计的类似物。通过纸片扩散法和肉汤微量稀释法评估抗菌活性。使用BALB 3T3 NRU试验和MTT染料还原试验来确定安全性和抗增殖活性。
所研究的类似物具有低毒性且对光安全。DTTyr10对MCF - 7细胞表现出最大的选择性。在第1位含有氟化苯丙氨酸的DT4F是新化合物中最有效的抗菌剂。与天然丝氨酸残基相比，在第10位引入苏氨酸导致新肽的抗增殖作用增强。
所获得的构效关系数据表明，测试系列中最有前景的化合物是FLPLIGRVL--GILNH，其中第10位的丝氨酸残基被疏水性更强的含羟基酪氨酸残基取代。在第1位含有氟化苯丙氨酸的类似物DT4F对两种测试肿瘤细胞系均具有最高的抗增殖作用，同时在最低抑菌浓度（80 µg/mL）下具有良好的抗菌特性，但它比母体DTA分子具有更高的细胞毒性和光毒性，并且在pH 9条件下24小时内不稳定。
