The molecular recognition and interaction of CphA from Aeromonas hydrophila with imipenem (Imip) and biapenem (Biap) were studied by means of the combined use of fluorescence spectra and molecular docking. The results showed that both the fluorescence quenching of CphA by Imip and Biap were caused through the combined dynamic and static quenching, and the latter was dominating in the process; the microenvironment and conformational of CphA were altered upon the addition of Imip and Biap from synchronous and three-dimensional fluorescence. The binding of CphA with Imip or Biap caused a conformational change in the loop of CphA, and through the conformational change, the loop opened the binding pocket of CphA to allow for an induced fit of the newly introduced ligand. In the binding of CphA with Imip, the whole molecule entered into the active pocket of CphA. The binding was driven by enthalpy change, and the binding force between them was mainly hydrogen bonding and Van der Waals force; whereas in the binding of CphA with Biap, only the beta-lactam ring of Biap entered into the binding pocket of CphA while the side chain was located outside the active pocket. The binding was driven by the enthalpy change and entropy change together, and the binding force between them was mainly electrostatic interaction. This study provided an insight into the recognition and binding of CphA with antibiotics, which may be helpful for designing new substrate for beta-lactamase and developing new antibiotics resistant to superbugs.

中文翻译：

---

光谱分析与分子对接相结合，对嗜水气单胞菌CphA与亚胺培南和比安培南的识别和相互作用。

通过荧光光谱和分子对接的结合，研究了嗜水气单胞菌CphA与亚胺培南（Imip）和比安培南（Biap）的分子识别和相互作用。结果表明，Imip和Biap对CphA的荧光猝灭均是由动态和静态猝灭共同引起的，而后者在该过程中占主导。从同步和三维荧光中添加了Imip和Biap后，CphA的微环境和构象发生了改变。CphA与Imip或Biap的结合在CphA环中引起构象变化，并且通过构象变化，该环打开了CphA的结合口袋，以允许新引入的配体的诱导配合。在CphA与Imip的结合中，整个分子进入了CphA的活性口袋。结合是由焓变驱动的，它们之间的结合力主要是氢键和范德华力。而在CphA与Biap的结合中，只有Biap的β-内酰胺环进入CphA的结合口袋，而侧链位于活性口袋的外部。结合是由焓变和熵变共同驱动的，它们之间的结合力主要是静电相互作用。这项研究提供了对CphA与抗生素的识别和结合的见解，这可能有助于设计β-内酰胺酶的新底物和开发对超级细菌具有抗性的新抗生素。它们之间的结合力主要是氢键和范德华力。而在CphA与Biap的结合中，只有Biap的β-内酰胺环进入CphA的结合口袋，而侧链位于活性口袋的外部。结合是由焓变和熵变共同驱动的，它们之间的结合力主要是静电相互作用。这项研究提供了对CphA与抗生素的识别和结合的见解，这可能有助于设计β-内酰胺酶的新底物和开发对超级细菌具有抗性的新抗生素。它们之间的结合力主要是氢键和范德华力。而在CphA与Biap的结合中，只有Biap的β-内酰胺环进入CphA的结合口袋，而侧链位于活性口袋的外部。结合是由焓变和熵变共同驱动的，它们之间的结合力主要是静电相互作用。这项研究提供了对CphA与抗生素的识别和结合的见解，这可能有助于设计β-内酰胺酶的新底物和开发对超级细菌具有抗性的新抗生素。结合是由焓变和熵变共同驱动的，它们之间的结合力主要是静电相互作用。这项研究提供了对CphA与抗生素的识别和结合的见解，这可能有助于设计β-内酰胺酶的新底物和开发对超级细菌具有抗性的新抗生素。结合是由焓变和熵变共同驱动的，它们之间的结合力主要是静电相互作用。这项研究提供了对CphA与抗生素的识别和结合的见解，这可能有助于设计β-内酰胺酶的新底物和开发对超级细菌具有抗性的新抗生素。