摘要

T7噬菌体（噬菌体）已被基因工程携带lacZ操纵子，在噬菌体感染过程中实现β-半乳糖苷酶（β-gal）的过表达并允许增强的大肠杆菌（大肠杆菌）比色检测。 在噬菌体感染大肠杆菌之后，使用比色底物监测释放的β-gal的酶活性。 与对照T7噬菌体相比，我们的T7lacZ噬菌体在噬菌体感染后产生显着更高水平的β-gal表达，从而使大肠杆菌细胞的检测下限成为可能。 使用这种工程化的T7lacZ噬菌体，我们能够在7小时内检测10 CFU·mL-1的大肠杆菌细胞。 此外，我们展示了使用我们的T7lacZ噬菌体对噬菌体进行基于噬菌体的细菌抗生素耐药谱分析以及随后的β-gal表达来检测大肠杆菌菌株的抗生素抗性谱的潜力。

T7 bacteriophages (phages) have been genetically engineered to carry the lacZ operon, enabling the overexpression of beta-galactosidase (β-gal) during phage infection and allowing for the enhanced colorimetric detection of Escherichia coli (E. coli). Following the phage infection of E. coli, the enzymatic activity of the released β-gal was monitored using a colorimetric substrate. Compared with a control T7 phage, our T7lacZ phage generated significantly higher levels of β-gal expression following phage infection, enabling a lower limit of detection for E. colicells. Using this engineered T7lacZ phage, we were able to detect E. coli cells at 10 CFU·mL–1within 7 h. Furthermore, we demonstrated the potential for phage-based sensing of bacteria antibiotic resistance profiling using our T7lacZ phage, and subsequent β-gal expression to detect antibiotic resistant profile of E. coli strains.

https://pubs.acs.org/doi/abs/10.1021/acssensors.7b00021