School of Mechanical Engineering and Automation, Beihang University, Beijing, 100083, China.
State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
J Nanobiotechnology. 2022 Aug 6;20(1):364. doi: 10.1186/s12951-022-01532-4.
Magnetosomes (BMPs) are organelles of magnetotactic bacteria (MTB) that are responsible for mineralizing iron to form magnetite. In addition, BMP is an ideal biomaterial that is widely used in bio- and nano-technological applications, such as drug delivery, tumor detection and therapy, and immunodetection. The use of BMPs to create multifunctional nanocomposites would further expand the range of their applications.
In this study, we firstly demonstrate that the extracted BMP can remineralize in vitro when it is exposed to AgNO solution, the silver ions (Ag) were transported into the BMP biomembrane (MM) and mineralized into a silver crystal on one crystal plane of FeO. Resulting in the rapid synthesis of an Ag-FeO hybrid BMP (BMP-Ag). The synergy between the biomembrane, FeO crystal and unmineralized iron enabled the remineralization of BMPs at an Ag concentration ≥ 1.0 mg mL. The BMP-Ag displayed good biocompatibility and antibacterial activity. At a concentration of 2.0 mg/mL, the BMP-Ag and biomembrane removed Ag-FeO NPs inhibited the growth of gram-negative and gram-positive bacteria. Thus using BMP-Ag as a wound dressing can effectively enhance the contraction of infected wounds.
This study represents the first successful attempt to remineralize organelles ex vivo, realizing the biosynthesis of hybrid BMP and providing an important advancement in the synthesis technology of multifunctional biological nanocomposites.
磁小体（BMPs）是趋磁细菌（MTB）的细胞器，负责将铁矿化形成磁铁矿。此外，BMP 是一种理想的生物材料，广泛应用于生物和纳米技术应用，如药物输送、肿瘤检测和治疗以及免疫检测。利用 BMP 制造多功能纳米复合材料将进一步扩大其应用范围。
在这项研究中，我们首先证明，提取的 BMP 在暴露于 AgNO 溶液时可以在体外再矿化，银离子（Ag）被运送到 BMP 生物膜（MM）中，并在 FeO 的一个晶面上矿化为银晶体。从而快速合成了 Ag-FeO 杂化 BMP（BMP-Ag）。生物膜、FeO 晶体和未矿化铁之间的协同作用使 BMP 在 Ag 浓度≥1.0mg/mL 时再矿化。BMP-Ag 表现出良好的生物相容性和抗菌活性。在 2.0mg/mL 的浓度下，BMP-Ag 和生物膜去除 Ag-FeO NPs 抑制了革兰氏阴性菌和革兰氏阳性菌的生长。因此，使用 BMP-Ag 作为伤口敷料可以有效增强感染伤口的收缩。
这项研究代表了首次成功尝试对细胞器进行体外再矿化，实现了杂化 BMP 的生物合成，并为多功能生物纳米复合材料的合成技术提供了重要进展。
