The conjugation of antibiotics with polymers is rarely done, but it might be a promising alternative to low-molecular-weight derivatization. The two penicillins penicillin G (PenG) and penicillin V (PenV) were attached to the end groups of different water-soluble poly(2-oxazoline)s (POx) via their carboxylic acid function. This ester group was shown to be more stable against hydrolysis than the β-lactam ring of the penicillins. The conjugates are still antimicrobially active and up to 20 times more stable against penicillinase catalyzed hydrolysis. The antibiotic activity of the conjugates against Staphylococcus aureus in the presence of penicillinase is up to 350 times higher compared with the free antibiotics. Conjugates with a second antimicrobial function, a dodecyltrimethylammonium group (DDA–X), at the starting end of the PenG and PenV POx conjugates are more antimicrobially active than the conjugates without DDA–X and show high activity in the presence of penicillinase. For example, the conjugates DDA–X–PEtOx–PenG and DDA–X–PEtOx–PenV are 200 to 350 times more active against S. aureus in the presence of penicillinase and almost as effective as the penicillinase stable cloxacollin (Clox) under these conditions. These conjugates show even greater activity compared to cloxacollin without this enzyme present. Further, both conjugates kill Escherichia coli more effectively than PenG and Clox.

中文翻译：

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聚（2-恶唑啉）-抗生素与青霉素结合

很少将抗生素与聚合物结合，但它可能是低分子量衍生化的有前途的替代方法。两个青霉素青霉素G（PenG）和青霉素V（PenV）通过其羧酸功能连接到不同的水溶性聚（2-恶唑啉）（POx）的端基上。已显示该酯基团比青霉素的β-内酰胺环对水解更稳定。结合物仍然具有抗微生物活性，并且对青霉素酶催化的水解具有高达20倍的稳定性。缀合物对金黄色葡萄球菌的抗菌活性与游离抗生素相比，存在青霉素酶的情况要高出350倍。在PenG和PenV POx结合物的起始端，具有第二种抗菌功能的结合物（十二烷基三甲基铵基团（DDA–X））比没有DDA–X的结合物具有更高的抗菌活性，并且在存在青霉素酶的情况下表现出高活性。例如，在青霉素酶存在下，结合物DDA–X–PEtOx–PenG和DDA–X–PEtOx–PenV对金黄色葡萄球菌的活性高200至350倍，在这些条件下，其稳定性几乎与稳定于青霉素酶的cloxacollin（Clox）一样。条件。与不存在这种酶的cloxacollin相比，这些结合物显示出更高的活性。此外，两种结合物都比PenG和Clox更有效地杀死大肠杆菌。