Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States.
Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States.
ACS Chem Biol. 2023 Sep 15;18(9):2063-2072. doi: 10.1021/acschembio.3c00351. Epub 2023 Sep 6.
The bacterial cell envelope provides a protective barrier that is challenging for small molecules and biomolecules to cross. Given the anionic nature of both Gram-positive and Gram-negative bacterial cell envelopes, negatively charged molecules are particularly difficult to deliver into these organisms. Many strategies have been employed to penetrate bacteria, ranging from reagents such as cell-penetrating peptides, enzymes, and metal-chelating compounds to physical perturbations. While cationic polymers are known antimicrobial agents, polymers that promote the permeabilization of bacterial cells without causing high levels of toxicity and cell lysis have not yet been described. Here, we investigate four polymers that display a cationic poly(2-(dimethylamino)ethyl methacrylate () block for the internalization of an anionic adenosine triphosphate (ATP)-based chemical probe into and . We evaluated two polymer architectures, linear and micellar, to determine how shape and hydrophobicity affect internalization efficiency. We found that, in addition to these reagents successfully promoting probe internalization, the probe-labeled cells were able to continue to grow and divide. The micellar structures in particular were highly effective for the delivery of the negatively charged chemical probe. Finally, we demonstrated that these cationic polymers could act as general permeabilization reagents, promoting the entry of other molecules, such as antibiotics.
细菌的细胞膜提供了一个具有挑战性的屏障，小分子和生物分子很难穿越。鉴于革兰氏阳性和革兰氏阴性细菌细胞膜的阴离子性质，带负电荷的分子尤其难以输送到这些生物体中。已经采用了许多策略来穿透细菌，从穿透肽、酶和金属螯合化合物等试剂到物理干扰。虽然阳离子聚合物是已知的抗菌剂，但尚未描述能够促进细菌细胞通透性而不引起高毒性和细胞裂解的聚合物。在这里，我们研究了四种显示阳离子聚（2-（二甲氨基）乙基甲基丙烯酸酯（）嵌段的聚合物，用于将阴离子三磷酸腺苷（ATP）基化学探针内化为 和 。我们评估了两种聚合物结构，线性和胶束，以确定形状和疏水性如何影响内化效率。我们发现，除了这些试剂成功地促进探针内化之外，标记探针的细胞还能够继续生长和分裂。特别是胶束结构非常有效地输送带负电荷的化学探针。最后，我们证明这些阳离子聚合物可以作为通用的通透化试剂，促进其他分子（如抗生素）的进入。
