WHAT IS THE PROBLEM: DENTAL CARIES
Dental Caries, or tooth decay, is one of the most common diseases in the world. Though children are mostly exposed to dental caries, people are susceptible to this disease no matter their age. The main cause of it is the harmful bacteria on the teeth. Bacteria, mainly S. sobrinua and S. mutans, assemble on the enamel and form biofilm. These bacteria then feed on food left on the teeth and excrete organic acid that mineralizes and broke the enamel. Dental Caries not only cause great pain and disruption of oral health but also increase the risk of infection of other bodies, which will lead to diseases such as Arthritis. Current treatments include topical fluoridization and tooth filling. However, many of them contain significant risks. The best way of eliminating Dental Caries is unclear.
WHOW IS CLYR BE TAKEN INTO CONSIDERATION
ClyR is a common chimeric lysin that bacteriophage produces to attack target microbes. Previous experiments have shown that ClyR can specifically eliminate Streptococcal microbes which most caries-causing pathogens are. Therefore, its Specificity and Efficiency make ClyR a promising treatment.
WHAT IS OUR GOAL
Figure. Flow chat of our project design
Dr. Phage's goal is to Create a gene-engineered E. coli strain containing ClyR gene and a-L-arabinofuranosidase(Arab) gene. Arab is an enzyme used to hydrolyze arabinose from arabinoxylans, a carbohydrate that appears normally in foods. In the strain, ClyR gene is recombined with a promoter that can be induced by arabinose to express ClyR outside of bacteria to function.
HOW IS OUR STRAIN CREATED
Firstly, Arab gene and ClyR gene are received and amplified through PCR and checked with Gel electrophoresis. Then Plasmid vectors are cut with a restriction enzyme and purified with Gel electrophoresis. DNA ligase is used to recombine both gene with different Plasmid vectors, and the plasmids are transformed into the strain through Electric shock transformation. The effectiveness of the cell is evaluated with the measure of arabinose concentration, A280 protein concentration, and Fluorescence intensity by using GFP substituting ClyR.
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