Sharma Deepali, Ashaduzzaman Md, Golabi Mohsen, Shriwastav Amritanshu, Bisetty Krishna, Tiwari Ashutosh
Department of Chemistry, Durban University of Technology , Durban 4000, South Africa.
Biosensors and Bioelectronics Centre, IFM, Linköping University , Linköping 58183, Sweden.
ACS Appl Mater Interfaces. 2015 Nov 4;7(43):23848-56. doi: 10.1021/acsami.5b06617. Epub 2015 Oct 26.
Molecular imprinting generates robust, efficient, and highly mesoporous surfaces for biointeractions. Mechanistic interfacial interaction between the surface of core substrate and protein corona is crucial to understand the substantial microbial toxic responses at a nanoscale. In this study, we have focused on the mechanistic interactions between synthesized saponin imprinted zinc oxide nanohoneycombs (SIZnO NHs), average size 80-125 nm, surface area 20.27 m(2)/g, average pore density 0.23 pore/nm and number-average pore size 3.74 nm and proteins corona of bacteria. The produced SIZnO NHs as potential antifungal and antibacterial agents have been studied on Sclerotium rolfsii (S. rolfsii), Pythium debarynum (P. debarynum) and Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), respectively. SIZnO NHs exhibited the highest antibacterial (∼50%) and antifungal (∼40%) activity against Gram-negative bacteria (E. coli) and fungus (P. debarynum), respectively at concentration of 0.1 mol. Scanning electron spectroscopy (SEM) observation showed that the ZnO NHs ruptured the cell wall of bacteria and internalized into the cell. The molecular docking studies were carried out using binding proteins present in the gram negative bacteria (lipopolysaccharide and lipocalin Blc) and gram positive bacteria (Staphylococcal Protein A, SpA). It was envisaged that the proteins present in the bacterial cell wall were found to interact and adsorb on the surface of SIZnO NHs thereby blocking the active sites of the proteins used for cell wall synthesis. The binding affinity and interaction energies were higher in the case of binding proteins present in gram negative bacteria as compared to that of gram positive bacteria. In addition, a kinetic mathematical model (KMM) was developed in MATLAB to predict the internalization in the bacterial cellular uptake of the ZnO NHs for better understanding of their controlled toxicity. The results obtained from KMM exhibited a good agreement with the experimental data. Exploration of mechanistic interactions, as well as the formation of bioconjugate of proteins and ZnO NHs would play a key role to interpret more complex biological systems in nature.
分子印迹为生物相互作用生成了坚固、高效且具有高度介孔性的表面。核心底物表面与蛋白质冠层之间的界面相互作用机制对于理解纳米尺度下显著的微生物毒性反应至关重要。在本研究中，我们聚焦于合成的皂苷印迹氧化锌纳米蜂窝（SIZnO NHs）与细菌蛋白质冠层之间的相互作用机制，SIZnO NHs平均尺寸为80 - 125 nm，表面积为20.27 m²/g，平均孔密度为0.23个孔/nm，数均孔径为3.74 nm。已分别在齐整小核菌（S. rolfsii）、德巴利腐霉（P. debarynum）以及大肠杆菌（E. coli）、金黄色葡萄球菌（S. aureus）上研究了所制备的作为潜在抗真菌和抗菌剂的SIZnO NHs。SIZnO NHs在浓度为0.1 mol时，对革兰氏阴性菌（大肠杆菌）和真菌（德巴利腐霉）分别表现出最高的抗菌活性（约50%）和抗真菌活性（约40%）。扫描电子光谱（SEM）观察表明，ZnO NHs破坏了细菌细胞壁并内化到细胞中。使用革兰氏阴性菌（脂多糖和视黄醇结合蛋白Blc）和革兰氏阳性菌（葡萄球菌蛋白A，SpA）中存在 的结合蛋白进行了分子对接研究。据设想，发现细菌细胞壁中存在的蛋白质会与SIZnO NHs表面相互作用并吸附，从而阻断用于细胞壁合成的蛋白质的活性位点。与革兰氏阳性菌中的结合蛋白相比，革兰氏阴性菌中的结合蛋白的结合亲和力和相互作用能更高。此外，在MATLAB中开发了一个动力学数学模型（KMM）来预测ZnO NHs在细菌细胞摄取中的内化情况，以便更好地理解它们的可控毒性。从KMM获得的结果与实验数据显示出良好的一致性。探索相互作用机制以及蛋白质与ZnO NHs生物共轭物的形成对于解释自然界中更复杂的生物系统将起到关键作用。
