Department of Applied Chemistry , National Chiao Tung University , Hsinchu 300 , Taiwan.
Master Program in Microbiology and Immunology, School of Medicine , Tzu Chi University , Hualien 970 , Taiwan.
Anal Chem. 2019 Aug 6;91(15):10335-10342. doi: 10.1021/acs.analchem.9b02964. Epub 2019 Jul 23.
() strains are common nosocomial pathogens that can cause infections and can easily become resistant to antibiotics. Thus, analytical methods that can be used to rapidly identify from complex samples should be developed. Tail fiber proteins derived from the tail fibers of bacteriophages can recognize specific bacterial surface polysaccharides. For example, recombinant tail proteins, such as TF2 and TF6 derived from the tail fibers of bacteriophages ϕAB2 and ϕAB6, can recognize clinical isolates M3237 and 54149, respectively. Thus, TF2 and TF6 can be used as probes to target specific strains. Generally, TF2 and TF6 are tagged with a hexahistidine (His) for ease of purification. Given that His possesses specific affinity toward alumina through His-Al chelation, TF2- and TF6-immobilized alumina-coated magnetic nanoparticles (FeO@AlO MNPs) were generated through chelation under microwave heating (power, 900 W) for 60 s in this study. The as-prepared TF2-FeO@AlO and TF6-FeO@AlO MNPs were used as affinity probes to trap trace M3237 and 54149, respectively, from sample solutions. Matrix-assisted laser desorption/ionization mass spectrometry capable of identifying bacteria on the basis of the obtained fingerprint mass spectra of intact bacteria was used as the detection tool. Results demonstrated that the current approach can be used to distinguish M3237 from 54149 by using TF2-FeO@AlO and TF6-FeO@AlO MNPs as affinity probes. Furthermore, the limits of detection of the current method for M3237 and 54149 are ∼10 and ∼10 cells mL, respectively. The feasibility of using the developed method to selectively detect M3237 and 54149 from complex serum samples was demonstrated.
() 菌株是常见的医院病原体，可以引起感染，并且很容易对抗生素产生耐药性。因此，应该开发能够快速鉴定复杂样本中 的分析方法。噬菌体尾丝蛋白可以识别特定的细菌表面多糖。例如，来自噬菌体 ϕAB2 和 ϕAB6 尾丝的重组尾蛋白 TF2 和 TF6 可以分别识别临床分离株 M3237 和 54149。因此，TF2 和 TF6 可以用作针对特定 菌株的探针。通常，TF2 和 TF6 被标记为六组氨酸 (His) 以方便纯化。由于 His 通过 His-Al 螯合对氧化铝具有特定的亲和力，因此本研究通过微波加热（功率，900 W）下 60 s 的螯合生成 TF2 和 TF6 固定化氧化铝涂覆的磁性纳米颗粒 (FeO@AlO MNPs)。制备的 TF2-FeO@AlO 和 TF6-FeO@AlO MNPs 分别用作亲和探针，从样品溶液中捕获痕量的 M3237 和 54149。基质辅助激光解吸/电离质谱能够根据完整细菌获得的指纹质谱图识别细菌，被用作检测工具。结果表明，当前方法可以使用 TF2-FeO@AlO 和 TF6-FeO@AlO MNPs 作为亲和探针来区分 M3237 和 54149。此外，当前方法对 M3237 和 54149 的检测限分别约为 10 和 10 个细胞 mL-1。证明了该方法从复杂的血清样本中选择性检测 M3237 和 54149 的可行性。
