Mouthwash A Closer Look at Biofilms

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MouthwashA Closer Look at Biofilms
Picture taken from http//www.ehponline.org/docs/
1998/106-12/innova-biofilmB.JPG
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Introduction

• Introduction
• What we want?
• Mechanism of action of S. mutans
• Methods
• Ways to block adhesion
• Discussion

What we want?

• Target the biofilm, before it develops.
• As mentioned last week, biofilms on our teeth are
  formed between the interaction with S. mutans.
• If we prevent this interaction, we can prevent
  biofilm formation.
• Without a biofilm, bacterial species in our mouth
  are vulnerable and can hopefully be destroyed
  with simpler methods.

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Introduction

• Introduction
• What we want?
• Mechanism of action of S. mutans
• Methods
• Ways to block adhesion
• Discussion

Mechanism of action of S. mutans
Step 1
pac
Step 2
Expression of the cell surface adhesion antigen
PAc
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Methods

• Introduction
• What we want?
• Mechanism of action of S. mutans
• Methods
• Ways to block adhesion
• Discussion

Ways to block adhesion

• Design a strain of S. lactis with the pac gene.
• Binding of both S. lactis and S. mutans would
  force competitive binding.
• If possible, we can have our strain grow at a
  wanted rate that would enable it to block off S.
  mutans.

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Methods

• Introduction
• What we want?
• Mechanism of action of S. mutans
• Methods
• Ways to block adhesion
• Discussion

Ways to Block Adhesion

• Use antibodies
• 1 Problem How can we connect this to synthetic
  biology?
• To my knowledge, I havent seen Abs in the
  registry, so if we could make it work, adding new
  parts is always a plus.
• Design our Abs to bind to the PAc antigen and
  destroy S. mutans with WBC.

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Methods

• Introduction
• What we want?
• Mechanism of action of S. mutans
• Methods
• Ways to block adhesion
• Discussion

Ways to Block Adhesion
Binding of S. mutans
Binding of Ab
Binding of Ab, with neutrophil ready to destry
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Discussion

• Introduction
• What we want?
• Mechanism of action of S. mutans
• Methods
• Ways to block adhesion
• Discussion

What Next?

• Now that we hopefully prevented biofilm
  formation, we must look on how long this will
  last?
• Still need to have our strain smell good, taste
  good, out compete S. mutans, and only have to use
  once a week or less.
• Possibily use one strain of S. lactis for biofilm
  prevention, and use E. coli for smell, taste,
  etc.
• Would it be ideal to use 2 strains in our
  mouthwash or toothpaste?

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References

• Iwaki M, Okahashi N, Takahashi I, Kanamoto T,
  Sugita-Konishi Y, Aibara K, and Koga T. Oral
  immunization with recombinant Streptococcus
  lactis carrying the Streptococcus mutans surface
  protein antigen gene. Infect Immun 1990 Sep
  58(9) 2929-34. pmid2117575.
• Kruger C, Hu Y, Pan Q, Marcotte H, Hultberg A,
  Delwar D, van Dalen PJ, Pouwels PH, Leer RJ,
  Kelly CG, van Dollenweerd C, Ma JK, and
  Hammarstrum L. In situ delivery of passive
  immunity by lactobacilli producing single-chain
  antibodies. Nat Biotechnol 2002 Jul 20(7) 702-6.
  doi10.1038/nbt0702-702 pmid12089555