Team:LMU-Munich/Application/Pretest

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==Co-cultivation of ''B. subtilis'' with nasal swabs==
==Co-cultivation of ''B. subtilis'' with nasal swabs==
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[[Image:LMU14_pretestcocultivationW168.png|thumb|600px|center|Fig. 1: a represatative selection of the outcome of this test. The heatinaktivation of the probes +W168 shows that ''B. subtilis'' can co-exist with the nasal microbiome]]
 
The first test targets the first two questions from above. Nasal swabs were taken from the team members and applied to an LB-plate and subsequently innoculated in a DSM-culture (to enable sporulation), which was split into two probes. To one probe ''B. subtilis'' was added. These were incubated for at least 24 hours, to enable sporulating bacteria to form spores. The spores are required for the detection, as only spores overlive a heat inactivation of 80 °C for over 20 minutes. One half of each probe was heat inactivated, while the other was not to distinguish all bacteria from spore formating bacteria. They were plated on LB-plates in different dilutions.
The first test targets the first two questions from above. Nasal swabs were taken from the team members and applied to an LB-plate and subsequently innoculated in a DSM-culture (to enable sporulation), which was split into two probes. To one probe ''B. subtilis'' was added. These were incubated for at least 24 hours, to enable sporulating bacteria to form spores. The spores are required for the detection, as only spores overlive a heat inactivation of 80 °C for over 20 minutes. One half of each probe was heat inactivated, while the other was not to distinguish all bacteria from spore formating bacteria. They were plated on LB-plates in different dilutions.
 +
[[Image:LMU14_pretestcocultivationW168.png|thumb|600px|center|Fig. 1: A representative selection of the outcome of this test. The heat inaktivation of the probes with W168 shows that ''B. subtilis'' can co-exist with the nasal microbiome, as colonies deriving presumably from ''B. subtilis'' spores grew, while only few are visible on the plates of the heat inactivation without W168.]]
''<b>Outcome</b>'':
''<b>Outcome</b>'':

Revision as of 01:20, 18 October 2014

Pretest

The application of BaKillus as a nasal spray implies the requirement of B. subtilis to survive the environment of the nasal mucosa. This does not go without saying, as B. subtilis naturally exists in the soil and not all microbes can co-exist. Additionally the bacteria have to cope with the host immune system. Naturally nasal-microbes have evolved to co-exist with each other and the immunesystem. So can B. subtilis, and in future BaKillus, be introduced in this complex system and live long enough to accomplish its mission to hunt, disintigrate biofilms and destroy pathogens located within.

To test this we were intrigued by the idea to utilize the B. subtilis wildtype, which holds a GRAS-status, and couragious team members in a quest to find answers. But first we wanted to clarify legal issues related to this.

LEGAL ISSUES

The main questions are the following

  • Is it possible to reliably detect B. subtilis in an assay to accomplish a convincing conclusion?
  • Can B. subtilis co-exist with the nasal microbiome?
  • Can B. subtilis live long enough in the nasal mucosa to be relevant for a medical treatment?

For this we conducted two tests:

  • Co-cultivation of B. subtilis with nasal swabs
  • Survival and detection of B. subtilis in the nasal mucosa

Co-cultivation of B. subtilis with nasal swabs

The first test targets the first two questions from above. Nasal swabs were taken from the team members and applied to an LB-plate and subsequently innoculated in a DSM-culture (to enable sporulation), which was split into two probes. To one probe B. subtilis was added. These were incubated for at least 24 hours, to enable sporulating bacteria to form spores. The spores are required for the detection, as only spores overlive a heat inactivation of 80 °C for over 20 minutes. One half of each probe was heat inactivated, while the other was not to distinguish all bacteria from spore formating bacteria. They were plated on LB-plates in different dilutions.


Fig. 1: A representative selection of the outcome of this test. The heat inaktivation of the probes with W168 shows that B. subtilis can co-exist with the nasal microbiome, as colonies deriving presumably from B. subtilis spores grew, while only few are visible on the plates of the heat inactivation without W168.

Outcome:

  • The nasal microbiome is quite different for most people
  • It is possible to reliably detect B. subtilis in the nasal microbiome
  • Mostly B. subtilis can co-exist with the nasal microbiome (with one exception not shown)
  • With B. subtilis the nasal microbiome can change, probably due to the fact, that B. subtilis already produces cannabalism toxins and other antimicrobial substances outcompeting some of the other bacteria

Hi there!

Welcome to our Wiki! I'm BaKillus, the pathogen-hunting microbe, and I'll guide you on this tour through our project. If you want to learn more about a specific step, you can simply close the tour and come back to it anytime you like. So let's start!

What's the problem?

First of all, what am I doing here? The problem is, pathogenic bacteria all around the world are becoming more and more resistant against antimicrobial drugs. One major reason for the trend is the inappropriate use of drugs. With my BaKillus super powers, I want to reduce this misuse and thus do my part to save global health.

Sensing of pathogens

To combat the pathogenic bacteria, I simply eavesdrop on their communication. Bacteria talk with each other via quorum sensing systems, which I use to detect them and trigger my responses.

Adhesion

The more specific and effective I can use my powers, the lower the danger is of provoking new resistance development. So I catch pathogens whenever I get hold of them and stick to them until my work is done.

Killing

Talking about my work - killing pathogens is finally what I am made for. In response to quorum sensing molecules of the pathogens, I export a range of antimicrobial substances leading to dissipation of biofilms and the killing of the targeted bacteria.

Suicide switch

When the job is done and all the bad guys are finished, you don't need a super hero anymore. So after fulfilling my work I say goodbye to the world by activating my suicide switch.

Application

Of course I'm not only a fictional hero, but a very real one. In two different prototypes, I could be used for diagnosis or treatment of pathogen-caused diseases. However, there is still a whole lot of regulational and economical questions that have to be answered before.

See you!

So now you know my short story - and it is time for me to return to my fight for a safer world. Feel free to take a closer look on my super powers, the process of my development or the plans for a medical application.

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