Team:Cambridge/Project

From 2011.igem.org

(Difference between revisions)
(→What purpose do reflectins have in these species?)
(→Achievements)
 
(132 intermediate revisions not shown)
Line 1: Line 1:
{{Template:Team:Cambridge/CAM_2011_TEMPLATE_HEAD}}
{{Template:Team:Cambridge/CAM_2011_TEMPLATE_HEAD}}
 +
Bact<b>iridescence</b> was based around the properties of [[Team:Cambridge/Project/Background | reflectin]], a squid protein with the highest refractive index of any known proteinaceous substance. In squid this protein forms complex platelets which act as [http://en.wikipedia.org/wiki/Bragg_reflector Bragg reflectors] to provide camouflage.
-
{|align="justify"
+
===Project Goals===
-
|You can write a background of your team here.  Give us a background of your team, the members, etc.  Or tell us more about something of your choosing.
+
-
|[[Image:Cambridge_logo.png|200px|right|frame]]
+
-
|-
+
-
|
+
-
''Tell us more about your project.  Give us background.  Use this is the abstract of your project.  Be descriptive but concise (1-2 paragraphs)''
+
-
|[[Image:Cambridge_team.png|right|frame|Your team picture]]
+
-
|-
+
-
|
+
-
|align="center"|[[Team:Cambridge | Team Example]]
+
-
|}
+
 +
We aimed to [[Team:Cambridge/Project/In_Vivo | express reflectin in ''E. coli'']] and to investigate its optical properties in order to build the groundwork for the manipulation of living structural colour. We also looked at the [[Team:Cambridge/Project/In_Vitro | over-expression of reflectin in ''E. coli'']], in order to obtain relatively pure samples of the protein for making thin films.
 +
Much of our work (particularly the in vivo work) simply hadn't been tried before, so, while we had high hopes, we could not be sure as to what would happen.
-
==Bactiridescence - Reflectin' the Future==
+
==Achievements==
 +
In one short summer the [[Team:Cambridge/Team | 2011 Cambridge team]] has produced a set of [[Team:Cambridge/Parts | BioBrick parts]] to allow future researchers to explore synthetic biology applications for structural colour.
-
Reflectins are a recently identified protein family rich in aromatic and sulphur-containing amino acids, responsible for the 'reflective' camouflage exhibited by certain cephalopods. To date, researchers have isolated the protein, over-expressed it in ''Escherichia coli'' and shown it to exhibit self-assembling behaviour and a changeable morphology which leads to dynamic manipulation of incident light.
+
===[[Team:Cambridge/Project/In_Vivo | In Vivo]]===
 +
Working with living cells we have;
 +
*[[Team:Cambridge/Project/Microscopy | Imaged squid tissue using novel techniques]] to explore the in vivo properties of reflectins.
 +
*Succesfully produced reflectins in ''E. coli''.
 +
*Characterised best practices for in vivo reflectin production.
 +
===[[Team:Cambridge/Project/In_Vitro | In Vitro]]===
 +
[[File:Cam_Multilayer_drop_1.jpg | right | thumb | 150px | A multilayer thin film]]
 +
By engineering ''E. coli'' to overexpress reflectins we have;
 +
*[[Team:Cambridge/Experiments/Protein_Purification | Purified reflectin]] and documented best practice for high purity yields.
 +
*Made [[Team:Cambridge/Project/Microscopy#Reflectin_Thin_Films | thin films]] which show structural colours.
 +
*Demonstrated the rapid colour changes possible with reflectin.
 +
**Videos of our thin films are available on [http://www.youtube.com/user/cambridgeigem2011 youtube].
-
Under in-vitro conditions ''Kramer et. al'' produced thin films, photonic gratings and fibres which exhibited  structural colour extending across the entire visual spectrum by varying the thickness. In particular the colour change was demonstrated to be reversible. It is hypothesized the colouration is a result of thin film interference.
+
===[[Team:Cambridge/Project/Gibthon | Software]]===
 +
[[File:Gibthon2.0beta.png | left | thumb | 100px | The Gibthon logo]]
 +
We contributed to [http://www.gibthon.org/ Gibthon], an open-source collection of web-based tools for construct design, fully compatible with both BioBrick standards and newer assembly techniques.
 +
*Greatly improved import and display of fragments (including support for [http://partsregistry.org/Main_Page partsregistry.org]).
 +
*Added tools to allow management of uploaded parts.
 +
<html><div style='clear:both'></div></html>
-
Within the Atlantic squid ''Loligo pealeii'', ''Morse et.al'' found a multi-layer alternating structure of iridophore platelets of reflectin and an unidentified material, each possessing different refractive indices. By studying tissue samples in-vitro the researchers observed conformational changes in the multi-layer structure due to phosphorylation. 
+
==[[Team:Cambridge/Project/Future | Future work]]==
-
 
+
By creating the first BioBrick parts for production of structural colour, we hope to facilitate further research. Although time did not allow us to explore the full potential of our project, we have some ideas for what could be done next.
-
As part of our iGEM project we propose to express reflectin in-vivo within ''Escherichia coli'' to reproduce the same multi-layer structure. Further we wish to demonstrate the ability to dynamically tune structural colour in-vivo through phosphorylation. Our work will directly impact upon the design of next-generation novel biosensors.
+
-
 
+
-
 
+
-
== Project Details==
+
-
 
+
-
 
+
-
=== Reflectin and its Properties - A summary of our literature review ===
+
-
 
+
-
In choosing our project we research all the papers we could find on reflectin and several on the squid species that have been studied.
+
-
 
+
-
====What species of squid have reflectin proteins?====
+
-
 
+
-
Reflectin was first identified in the Hawaiian bobtail ''Euprymna scolopes'' as the protein responsible for this species' iridescence. Reflectin 1a from ''E. scolopes'' has been successfully expressed in E.coli and purified [[#Kramer|[1]]]. Related proteins in ''Lolliguncula brevis'' and in squid of the genus ''Loligo'' have attracted much research interest due to their ability to actively control their iridescence, a property termed dynamic iridescence.
+
-
 
+
-
====What purpose do reflectins have in these species?====
+
-
Reflectins are contained within stacks of repeating membranous structures known as iridophores within cells in squid skin. Within these structures, the reflectin proteins self-assemble to form a natural '[[#Bragg|Bragg stack]]'. Along with other cell types with optical properties these Bragg stacks contribute to the squid's ability to camouflage itself and communicate with other animals via manipulation of incident light.
+
-
 
+
-
====What is a Bragg reflector?====
+
-
Bragg reflectors are structures of alternating layers of materials with different refractive indices. These structures dominantly reflect at a certain peak wavelength in relation to the individual separation of the layers. Each boundary layer exhibits partial reflection which through superposition lead to interference phenomena. The peak reflected wavelength is 4 times the spacing distance between layers whereby the path difference is such as to allow constructive interference. This is the fundamental principle behind thin film interference, responsible for the rainbow colours reflected by oil droplets on the surface of water and that present on soap films.
+
-
 
+
-
====What is dynamic iridescence and does work in squid?====
+
-
(membrane association)
+
-
Iridescence describes material colour change as the viewing angle or the angle of incidence of light is varied. However dynamic iridescence observed in certain squid genera is believed to be a result of neural control. Specifically, the application of the neurotransmitter Acetyl Choline (ACH) to fresh skin samples resulted in detectable post-translational modifications of the protein, namely phosphorylation. It is believed that phosphorylation of reflectin proteins cause changes in the chemical interactions within the nanoparticles reflectin forms in-vivo within the iridophore. These changes subsequently induce an alteration in the volume of protein platelets of reflectin and critically the thicknesses of reflectin layers in the iridophore. The path difference between incident light on individual layers is thus altered resulting in a shift in peak reflected wavelength and therefore colour.
+
-
 
+
-
====What is known about the nucleotide sequence of reflectins?====
+
-
No introns were found in the reflectin genes when reflectin genes amplified from  ''Euprymna scolopes'' genomic DNA were sequenced. (2)
+
-
 
+
-
====What is known about the unusual amino acid content of reflectins?====
+
-
 
+
-
====What is known about the structure of the reflectin proteins?====
+
-
 
+
-
====What are the differences and conserved sequences between different reflectins and between reflectins in different species?====
+
-
 
+
-
====What work has been done on expressing reflectins in E.coli?====
+
-
 
+
-
====What in vitro experiments have been performed on reflectins?====
+
-
 
+
-
====What are the properties of in vitro films of reflectin?====
+
-
 
+
-
==='''References'''===
+
-
<div id="Kramer"></div>
+
-
[http://www.nature.com/nmat/journal/v6/n7/abs/nmat1930.html] Kramer ''et al.'' '''The self-organizing properties of squid reflectin protein''' Nature Materials 533-538 VOL6 JULY 2007
+
-
<div id="Crookes"></div>
+
-
[http://www.sciencemag.org/content/303/5655/235.short] Crookes ''et al.'' '''Reflectins: The Unusual Proteins of Squid Reflective Tissues''' 235-238 SCIENCE VOL303 9 JANUARY 2004
+
-
 
+
-
=== The Experiments ===
+
-
 
+
-
 
+
-
 
+
-
 
+
-
=== Part 3 ===
+
-
 
+
-
== Results ==
+
{{Template:Team:Cambridge/CAM_2011_TEMPLATE_FOOT}}
{{Template:Team:Cambridge/CAM_2011_TEMPLATE_FOOT}}

Latest revision as of 02:52, 22 September 2011

Loading...
OVERVIEW
home
Bactiridescence was based around the properties of reflectin, a squid protein with the highest refractive index of any known proteinaceous substance. In squid this protein forms complex platelets which act as Bragg reflectors to provide camouflage.

Contents

Project Goals

We aimed to express reflectin in E. coli and to investigate its optical properties in order to build the groundwork for the manipulation of living structural colour. We also looked at the over-expression of reflectin in E. coli, in order to obtain relatively pure samples of the protein for making thin films.

Much of our work (particularly the in vivo work) simply hadn't been tried before, so, while we had high hopes, we could not be sure as to what would happen.

Achievements

In one short summer the 2011 Cambridge team has produced a set of BioBrick parts to allow future researchers to explore synthetic biology applications for structural colour.

In Vivo

Working with living cells we have;

In Vitro

A multilayer thin film

By engineering E. coli to overexpress reflectins we have;

  • Purified reflectin and documented best practice for high purity yields.
  • Made thin films which show structural colours.
  • Demonstrated the rapid colour changes possible with reflectin.
    • Videos of our thin films are available on youtube.

Software

The Gibthon logo

We contributed to Gibthon, an open-source collection of web-based tools for construct design, fully compatible with both BioBrick standards and newer assembly techniques.

  • Greatly improved import and display of fragments (including support for partsregistry.org).
  • Added tools to allow management of uploaded parts.

Future work

By creating the first BioBrick parts for production of structural colour, we hope to facilitate further research. Although time did not allow us to explore the full potential of our project, we have some ideas for what could be done next.


Retrieved from "http://2011.igem.org/Team:Cambridge/Project"