Difference between revisions of "Template:Toulouse"
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− | < | + | <meta charset="utf-8"> |
− | + | <title>iGEM Toulouse 2015</title> | |
− | + | <link rel="icon" href="https://static.igem.org/mediawiki/2015/2/2e/TLSE_ApiColi.png" type="image/png" style="width:10%;"/> | |
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− | + | <!-- ################################################################################################ --> | |
+ | <!-- ################################################################################################ --> | ||
+ | <!-- ################################################################################################ --> | ||
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+ | </html>{{Toulouse/nav}}<html> | ||
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− | + | <div class="wrapper row2 bgded" style="background-image:url('https://static.igem.org/mediawiki/2015/0/03/TLSE_bakcground.png');"> | |
− | + | <div id="pageintro"> | |
− | + | <!-- ################################################################################################ --> | |
− | + | <div class="title"> | |
− | + | <h2>Context</h2> | |
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− | + | </div> | |
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+ | <div id="breadcrumb" class="clear" style="display:none;"> | ||
+ | <ul> | ||
+ | <li><a href="#">foo</a></li> | ||
+ | <li><a href="#">2-Collapse of Bees</a></li> | ||
+ | <li><a href="#"><i>3-Varroa destructor</i></a></li> | ||
+ | <li><a href="#">4-Outbreak of Varroa</a></li> | ||
+ | <li><a href="#">5-Means to fight Varroa</a></li> | ||
+ | </ul> | ||
+ | </div> | ||
+ | <!-- ################################################################################################ --> | ||
+ | </div> | ||
+ | </div> | ||
+ | <!-- ################################################################################################ --> | ||
+ | <!-- ################################################################################################ --> | ||
+ | <!-- ################################################################################################ | ||
+ | <div class="wrapper row0 bgded" style="background-image:url('https://static.igem.org/mediawiki/2015/0/03/TLSE_bakcground.png')"> | ||
+ | |||
+ | |||
+ | |||
+ | <div class="shout"> | ||
+ | |||
+ | <div class="shout-content clear"> | ||
+ | <div class="title"> | ||
+ | <center> <h2>Context</h2> </center> | ||
+ | </div> | ||
+ | <center><img src="https://static.igem.org/mediawiki/2015/7/70/TLSE_context_BG.png"></center> | ||
+ | |||
+ | </div> | ||
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+ | <div class="wrapper row3"> | ||
− | + | <br> | |
− | ---- | + | <main class="container clear"> |
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+ | <div> | ||
+ | |||
+ | <p class="title"> | ||
+ | </p> | ||
+ | </div> | ||
− | + | <!-- | |
− | - | + | <a href="#varroa" style="font-size:20px;">link1</a><br><br> |
− | + | <a href="#varroa2" style="font-size:20px;">link2</a> | |
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+ | <div class="group center"> <!-- FIRST PARAGRAPH --> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | |||
+ | Bees excel in pollination and thus play an essential role in maintaining ecosystems. | ||
+ | By gathering pollen, they allow the reproduction of 84% of the plants that grow in Europe. | ||
+ | Bees are also responsible for the production of 35% of edible fruits and vegetables. Without | ||
+ | bees, tomatoes, apples, vines and many more would be as good as gone (see Figure 1 for some examples). | ||
+ | Among all bees, the domestic bee, <i>Apis mellifera</i>, which builds its swarm in hives provided | ||
+ | by man, is directly responsible for the production of honey, wax and propolis. Very often, | ||
+ | the swarms are selected for their honey production yield. | ||
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+ | </p> | ||
+ | </div> | ||
+ | |||
+ | |||
+ | |||
+ | <div class="group center"> | ||
+ | <br> | ||
+ | <img src="https://static.igem.org/mediawiki/2015/3/37/TLSE_context_fig1.png" /> | ||
+ | </div> | ||
+ | <div class="group center"> | ||
+ | <br> | ||
+ | <p>Figure 1: Examples of products dependent of bee pollination to reproduce</p> | ||
+ | </div> | ||
+ | |||
+ | |||
+ | <div class="group center"> <!-- FIRST PARAGRAPH --> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | According to the French INRA (Institut National de la Recherche Agronomique), | ||
+ | the bee extinction would represent an economical worldwide loss of 163 billion USD. | ||
+ | This huge number reflects the bees’ importance in the global ecosystem. | ||
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− | / | + | </p> |
− | + | </div> | |
− | + | ||
+ | <div> | ||
+ | |||
+ | <div class="subtitle"> | ||
+ | <h3>Domestic bees</h3> | ||
− | / | + | </div> |
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− | + | <div class="group center"> | |
− | . | + | <div class="one_half first"> |
+ | <p align="justify" style="font-size:15px;"> | ||
+ | <br> | ||
+ | There are three types of bees | ||
+ | living in a beehive: the worker | ||
+ | bees, the queen bee and the male | ||
+ | bees. In the colony, the work is | ||
+ | divided in such a way that each | ||
+ | caste is specialized in its activities. | ||
+ | The worker bees are infertile female | ||
+ | and represent the most numerous caste | ||
+ | in the beehive. Their main activities are | ||
+ | cleaning the beehive cells, ventilate the | ||
+ | beehive, cap the beehive cells containing | ||
+ | the bee eggs, feed the larvae, gather pollen and defend the colony. | ||
+ | The queen bee ensures the renewal of | ||
+ | the bee colony. | ||
+ | The male bees represent the infertilized eggs. | ||
+ | Their main activity is the reproductive function with the queen bee outside of the beehive. | ||
+ | </p> | ||
+ | </div> | ||
− | + | <div class="one_half"> | |
− | . | + | |
+ | <img src="https://static.igem.org/mediawiki/2015/2/28/TLSE_context_fig1bis.png"> | ||
+ | <p>The Queen, a Worker and a male (coming soon) | ||
+ | </p> | ||
+ | |||
+ | </div> | ||
+ | </div> | ||
+ | |||
+ | |||
+ | |||
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− | + | ||
+ | <div class="subtitle"> | ||
+ | <h3>Collapse of Bees</h3> | ||
+ | </div> | ||
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− | + | <div class="group center"> | |
− | + | <div class="one_half first"> | |
− | + | <img src="https://static.igem.org/mediawiki/2015/1/14/TLSE_context_fig1bis2.png" style="width:60%;"> | |
+ | </div> | ||
+ | <div class="one_half"> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | <br> | ||
+ | Over the last few decades, a decline in the honeybee population has been observed. In Europe 24% | ||
+ | of the domestic bee species are threatened of extinction. The more indicators you consider, the | ||
+ | more alarming appears the situation. The bee loss has a multifactorial origin. Among these factors, | ||
+ | the <b>Colony Collapse Disorder</b> (CCD) is one of the most important. CCD corresponds to a massive loss | ||
+ | of bee colonies. The causes of this syndrome are numerous: pesticides, viruses, parasites… among those, | ||
+ | a mite wisely named <i id="varroa">Varroa destructor</i> is one of the bee’s fiercest enemies. | ||
+ | </p> | ||
+ | </div> | ||
+ | </div> | ||
+ | <div class="subtitle"> | ||
+ | <h3><i>Varroa destructor</i></h3> | ||
+ | </div> | ||
+ | <div class="group center"> <!-- FIRST PARAGRAPH --> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | |||
+ | <i>Varroa destructor</i> is an obligatory ectoparasite | ||
+ | of bees. This means it is an external parasite | ||
+ | and it cannot survive without its host, the bee. | ||
+ | The varroa development cycle takes place in the | ||
+ | beehive cells in parallel of the bee development | ||
+ | cycle. The key individual of the varroa development | ||
+ | cycle is the adult female commonly named “founder”. | ||
+ | The founder reproduces exclusively in a brood cell | ||
+ | that represents the beehive cell containing a bee | ||
+ | larva. The founder reproduction occurs during the | ||
+ | phoretic phase where the varroa is moved from one | ||
+ | bee colony to the other by an adult bee. | ||
+ | </p> | ||
+ | </div> | ||
+ | |||
+ | |||
+ | |||
+ | <div class="group center"> | ||
+ | <br> | ||
+ | <img src="https://static.igem.org/mediawiki/2015/f/f2/TLSE_context_fig2.png" style="width:85%;height:55%;" /> | ||
+ | </div> | ||
+ | <div class="group center"> | ||
+ | <br> | ||
+ | <p>Figure 2: Synchronized life cycle of Honeybees and <i>Varroa destructor</i>.</p> | ||
+ | </div> | ||
+ | |||
+ | <div class="group center"> <!-- FIRST PARAGRAPH --> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | |||
+ | The mite varroa is originally an ectoparasite of Apis cerana, the Asian honey bee. | ||
+ | The first contact between varroa and Apis mellifera occurred in the 1950s in Asia. | ||
+ | During the following years, the infestation spread to Europe, Africa and America. | ||
+ | The first signs of this infestation were observed in Europe and North America in | ||
+ | the early 1980s. | ||
+ | The varroa mite is a particularly virulent parasite of Apis mellifera since the | ||
+ | European honeybee did not have time to develop an adaptive response to it. In | ||
+ | Asia on the contrary, Apis cerana and Varroa destructor co-evolved over the | ||
+ | centuries and reached a certain balance. Interestingly, the Asian honeybee is | ||
+ | capable of detecting the parasite’s presence and of getting rid of it. | ||
− | / | + | </p> |
− | + | </div> | |
− | + | ||
− | + | <div class="group center"> | |
+ | <br> | ||
+ | <img src="https://static.igem.org/mediawiki/2015/6/6b/TLSE_context_fig3.png" style="width:75%;height:55%;" /> | ||
+ | </div> | ||
+ | <div class="group center"> | ||
+ | <br> | ||
+ | <p>Figure 3: Effects exerted by Varroa destructor on honeybee and their consequences. | ||
+ | </p> | ||
+ | </div> | ||
+ | |||
+ | <div class="subtitle"> | ||
+ | <h3>Outbreak of <i>Varroa destructor</i> in the Western World</h3> | ||
+ | </div> | ||
+ | <div class="group center"> | ||
+ | <div class="one_half first"> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | |||
+ | The mite varroa is originally an ectoparasite | ||
+ | of Apis cerana, the Asian honey bee. The first | ||
+ | contact between varroa and Apis mellifera | ||
+ | occurred in the 1950s in Asia. During the | ||
+ | following years, the infestation spread to | ||
+ | Europe, Africa and America. The first signs | ||
+ | of this infestation were observed in Europe | ||
+ | and North America in the early 1980s. | ||
+ | The varroa mite is a particularly virulent | ||
+ | parasite of Apis mellifera since the European | ||
+ | honeybee did not have time to develop an adaptive | ||
+ | response to it. In Asia on the contrary, Apis cerana | ||
+ | and Varroa destructor co-evolved over the centuries | ||
+ | and reached a certain balance. Interestingly, the Asian | ||
+ | honeybee is capable of detecting the parasite’s presence | ||
+ | and of getting rid of it. | ||
− | |||
− | |||
+ | </p> | ||
+ | </div> | ||
− | + | <div class="one_half"> | |
− | + | ||
− | + | ||
+ | <img src="https://static.igem.org/mediawiki/2015/a/a6/TLSE_context_fig3bis.png" style="width:50%;"> | ||
+ | </div> | ||
+ | </div> | ||
− | + | <div class="subtitle"> | |
− | / | + | <h3>Means to fight <i>Varroa destructor</i></h3> |
− | / | + | </div> |
− | + | ||
− | + | ||
+ | <div class="group center"> | ||
+ | <table class="df"> | ||
+ | <tr> | ||
+ | <td> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | Search of tolerant or resistant bees through selection. | ||
+ | </p> | ||
+ | </td> | ||
+ | <td> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | TODO commentary | ||
+ | </p> | ||
+ | </td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | Those two types of methods are insufficient to totally eliminate varroas from a hive. | ||
+ | </p> | ||
+ | </td> | ||
+ | <td> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | Those two types of methods are insufficient to totally eliminate varroas from a hive. | ||
+ | TODO commentary | ||
+ | </p> | ||
+ | </td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | Use of chemical treatments. | ||
+ | </p> | ||
+ | </td> | ||
+ | <td> | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | This last type is the most effective | ||
+ | however none of the treatments has | ||
+ | a 100% effectiveness and their use | ||
+ | is often limited since bees generate | ||
+ | consumable products. | ||
+ | </p> | ||
+ | </td> | ||
+ | </tr> | ||
+ | </table> | ||
+ | </div> | ||
+ | </div> | ||
+ | |||
+ | <!-- | ||
+ | <p align="justify" style="font-size:15px;"> | ||
+ | <ul style="font-size:15px;"> | ||
+ | <li> | ||
+ | Search of tolerant or resistant bees through selection. | ||
+ | </li> | ||
+ | <li> | ||
+ | Use of “zoo-technique” or “bio-technique” means. | ||
+ | </li> | ||
+ | <li> | ||
+ | Use of chemical treatments. | ||
+ | </li> | ||
+ | </ul> | ||
− | + | This last type is the most effective however none of the treatments has a 100% effectiveness and their use is often limited since bees generate consumable products. The lack of effectiveness of those treatments (not to mention the resistance phenomena excepted) induces the presence in hives of enough Varroa to allow the population to grow beyond the dangerous threshold for a bee colony. And when any other treatment is used (usually annual treatments), they only eliminate 90% of the varroa population, which is insufficient to maintain the epidemic at safe levels. | |
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− | / | + | </p> |
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− | + | </main> | |
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− | # | + | <!-- ################################################################################################ --> |
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− | + | <!-- ################################################################################################ --> | |
− | + | <!-- ########################### SPONSORS ###################################################################### --> | |
− | + | <div class="wrapper row4"> | |
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− | / | + | <div class="container clear" style="padding-top:30px;"> |
− | + | <center><p class="maintitle"> | |
− | + | References | |
− | + | </p></center> | |
− | + | <br> | |
+ | <div class="clear"> | ||
+ | <ul> | ||
+ | <li> | ||
+ | [1] Boecking O, Genersch E. 2008. Varroosis – the Ongoing Crisis in Bee Keeping. J. Verbr. Lebensm. 3:221–228.</li> | ||
+ | <li> | ||
+ | [2] Le Conte Y, Arnold G, Trouiller J, Masson C, Chappe B, Ourisson G. 1989. Attraction of the parasitic mite varroa to the drone larvae of honey bees by simple aliphatic esters. Science 245:638–639.</li> | ||
− | + | <li> | |
− | + | [3] Methods for attracting honey bee parasitic mites. [accessed 2015 Jul 24]. | |
− | + | </li> | |
− | + | ||
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− | + | ||
− | / | + | <li> |
− | + | [4] Louis P, Flint HJ. 2009. Diversity, metabolism and microbial ecology of butyrate-producing bacteria from the human large intestine. FEMS Microbiol. Lett. 294:1–8. | |
− | + | </li> | |
− | # | + | [5] Atsumi S, Cann AF, Connor MR, Shen CR, Smith KM, Brynildsen MP, Chou KJY, Hanai T, Liao JC. 2008. Metabolic engineering of Escherichia coli for 1-butanol production. Metabolic Engineering 10:305–311. |
− | # | + | <li> |
− | # | + | [6] Wallace KK, Bao Z-Y, Dai H, Digate R, Schuler G, Speedie MK, Reynolds KA. 1995. Purification of Crotonyl-CoA Reductase from Streptomyces collinus and Cloning, Sequencing and Expression of the Corresponding Gene in Escherichia coli. European Journal of Biochemistry 233:954–962. |
+ | </li> | ||
+ | </ul> | ||
+ | </div> | ||
+ | <br> | ||
+ | </div> | ||
+ | </div> | ||
+ | <!-- ################################################################################################ --> | ||
+ | <!-- ################################################################################################ --> | ||
+ | <!-- ####################### FOOTER ######################################################################### --> | ||
+ | </html>{{Toulouse/footer}}<html> | ||
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Revision as of 13:54, 20 August 2015
Context
Bees excel in pollination and thus play an essential role in maintaining ecosystems. By gathering pollen, they allow the reproduction of 84% of the plants that grow in Europe. Bees are also responsible for the production of 35% of edible fruits and vegetables. Without bees, tomatoes, apples, vines and many more would be as good as gone (see Figure 1 for some examples). Among all bees, the domestic bee, Apis mellifera, which builds its swarm in hives provided by man, is directly responsible for the production of honey, wax and propolis. Very often, the swarms are selected for their honey production yield.
Figure 1: Examples of products dependent of bee pollination to reproduce
According to the French INRA (Institut National de la Recherche Agronomique), the bee extinction would represent an economical worldwide loss of 163 billion USD. This huge number reflects the bees’ importance in the global ecosystem.
Domestic bees
There are three types of bees
living in a beehive: the worker
bees, the queen bee and the male
bees. In the colony, the work is
divided in such a way that each
caste is specialized in its activities.
The worker bees are infertile female
and represent the most numerous caste
in the beehive. Their main activities are
cleaning the beehive cells, ventilate the
beehive, cap the beehive cells containing
the bee eggs, feed the larvae, gather pollen and defend the colony.
The queen bee ensures the renewal of
the bee colony.
The male bees represent the infertilized eggs.
Their main activity is the reproductive function with the queen bee outside of the beehive.
The Queen, a Worker and a male (coming soon)
Collapse of Bees
Over the last few decades, a decline in the honeybee population has been observed. In Europe 24%
of the domestic bee species are threatened of extinction. The more indicators you consider, the
more alarming appears the situation. The bee loss has a multifactorial origin. Among these factors,
the Colony Collapse Disorder (CCD) is one of the most important. CCD corresponds to a massive loss
of bee colonies. The causes of this syndrome are numerous: pesticides, viruses, parasites… among those,
a mite wisely named Varroa destructor is one of the bee’s fiercest enemies.
Varroa destructor
Varroa destructor is an obligatory ectoparasite of bees. This means it is an external parasite and it cannot survive without its host, the bee. The varroa development cycle takes place in the beehive cells in parallel of the bee development cycle. The key individual of the varroa development cycle is the adult female commonly named “founder”. The founder reproduces exclusively in a brood cell that represents the beehive cell containing a bee larva. The founder reproduction occurs during the phoretic phase where the varroa is moved from one bee colony to the other by an adult bee.
Figure 2: Synchronized life cycle of Honeybees and Varroa destructor.
The mite varroa is originally an ectoparasite of Apis cerana, the Asian honey bee. The first contact between varroa and Apis mellifera occurred in the 1950s in Asia. During the following years, the infestation spread to Europe, Africa and America. The first signs of this infestation were observed in Europe and North America in the early 1980s. The varroa mite is a particularly virulent parasite of Apis mellifera since the European honeybee did not have time to develop an adaptive response to it. In Asia on the contrary, Apis cerana and Varroa destructor co-evolved over the centuries and reached a certain balance. Interestingly, the Asian honeybee is capable of detecting the parasite’s presence and of getting rid of it.
Figure 3: Effects exerted by Varroa destructor on honeybee and their consequences.
Outbreak of Varroa destructor in the Western World
The mite varroa is originally an ectoparasite of Apis cerana, the Asian honey bee. The first contact between varroa and Apis mellifera occurred in the 1950s in Asia. During the following years, the infestation spread to Europe, Africa and America. The first signs of this infestation were observed in Europe and North America in the early 1980s. The varroa mite is a particularly virulent parasite of Apis mellifera since the European honeybee did not have time to develop an adaptive response to it. In Asia on the contrary, Apis cerana and Varroa destructor co-evolved over the centuries and reached a certain balance. Interestingly, the Asian honeybee is capable of detecting the parasite’s presence and of getting rid of it.
Means to fight Varroa destructor
Search of tolerant or resistant bees through selection. |
TODO commentary |
Those two types of methods are insufficient to totally eliminate varroas from a hive. |
Those two types of methods are insufficient to totally eliminate varroas from a hive. TODO commentary |
Use of chemical treatments. |
This last type is the most effective however none of the treatments has a 100% effectiveness and their use is often limited since bees generate consumable products. |
References
- [1] Boecking O, Genersch E. 2008. Varroosis – the Ongoing Crisis in Bee Keeping. J. Verbr. Lebensm. 3:221–228.
- [2] Le Conte Y, Arnold G, Trouiller J, Masson C, Chappe B, Ourisson G. 1989. Attraction of the parasitic mite varroa to the drone larvae of honey bees by simple aliphatic esters. Science 245:638–639.
- [3] Methods for attracting honey bee parasitic mites. [accessed 2015 Jul 24].
- [4] Louis P, Flint HJ. 2009. Diversity, metabolism and microbial ecology of butyrate-producing bacteria from the human large intestine. FEMS Microbiol. Lett. 294:1–8. [5] Atsumi S, Cann AF, Connor MR, Shen CR, Smith KM, Brynildsen MP, Chou KJY, Hanai T, Liao JC. 2008. Metabolic engineering of Escherichia coli for 1-butanol production. Metabolic Engineering 10:305–311.
- [6] Wallace KK, Bao Z-Y, Dai H, Digate R, Schuler G, Speedie MK, Reynolds KA. 1995. Purification of Crotonyl-CoA Reductase from Streptomyces collinus and Cloning, Sequencing and Expression of the Corresponding Gene in Escherichia coli. European Journal of Biochemistry 233:954–962.