Our STEM class is taught by Dr. Crowthers. We analyze and break down research papers, go over scientific research and engineering methods, as well as engaging in scientific writing. The focus of STEM I are our independent research projects that will be presented at fairs. Scroll down to learn more about my research project that I did in the MAMS lab!
This project aims to explore possible enhancements of phage activity using biosynthesized silver nanoparticles using curcumin, as well as possible restoration of antibiotic sensitivity in bacteria by utilizing the bacteria’s evolutionary trade-offs. I found out that after developing phage and biohybrid resistance independently, colistin-resistant bacteria restored some of its antibiotic sensitivity. The biohybrids created also showed significant inhibition of bacteria compared to phages alone.
The wide use of antibiotics has led to an emergence of antibiotic-resistant bacteria, steadily becoming a global health concern. Pathogens can develop resistance to drugs, making bacterial infections difficult to treat by limiting the use of antibiotics. Fortunately, phage resistance has shown to cause an evolutionary trade off where antibiotic resistant bacteria would have restored antibiotic sensitivity. It was predicted that if the antimicrobial abilities of phages T4 are enhanced using silver nanoparticles, then resistance to these phages or biohybrids can further increase antibiotic sensitivity in the model organism, E. coli K12. In this study, silver nanoparticles were synthesized using curcumin extract and combining the nanoparticles with phages T4 to create biohybrids, which allow for more effectiveness against bacteria. The bacteria were exposed to the biohybrids to develop resistance, and the colistin resistant bacteria have shown restored antibiotic sensitivity after resistance to the biohybrids. MIC assays were also performed with transformed E. coli that contains a plasmid with a gene for ampicillin resistance and compared to the ancestral bacteria. For the colistin resistant bacteria, the MIC values for the phage-resistant mutants and biohybrid-resistant mutants were not statistically significant, but both resistances resulted in increased antibiotic sensitivity. Combining silver nanoparticles synthesized with curcumin extract and phages together is not well-experimented with, but it has shown to be effective at killing bacteria, and the resistance to these biohybrids can lead restoration of antibiotic sensitivity. This help further expands the use of antibiotics that has been limited by resistant bacteria, and phage therapy.
Keywords: bacteriophages, antibiotic-resistant bacteria, silver nanoparticles, biohybrids, antibiotic sensitivity
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How effective are biosynthesized silver nanoparticles and phage T4 hybrids in restoring antibiotic sensitivity back to ampicillin and colistin resistant E. coli compared to phage resistance?
It is hypothesized that after developing resistance to the phage and silver nanoparticles biohybrids, the antibiotic resistant bacteria would have higher restoration of antibiotic sensitivity compared to phage resistance.
Figure 1: Graph of MIC values for colistin-resistant bacteria with colistin after development of phage and biohybrid resistance compared to the control group of ancestral colistin-resistant bacteria. Both the MIC values after the bacteria’s development of phage and biohybrid resistance were not statistically significant, but there was a statistical difference between the ancestral colistin resistance bacteria and both the phage and biohybrid resistant bacteria.
Figure 2: Table of ANOVA Post Hoc Statistical test results. The top table compares the volumes of curcumin extract, silver nitrate, and silver nanoparticles that are able to inhibit bacterial growth. The bottom table compares the group mean for MIC values of colistin resistant bacteria after developing phage and biohybrid resistance compared to the ancestral/control group.