Difference between revisions of "Part:BBa K525306"
Line 4: Line 4:
 
Fusion Protein of S-Layer SgsE and mCerulean
 
Fusion Protein of S-Layer SgsE and mCerulean
  
−
<!-- Add more about the biology of this part here
+
S-layers (crystalline bacterial surface layer) are crystal-like layers consisting of multiple protein monomers and can be found in various (archae-)bacteria. They constitute the outermost part of the cell wall. Especially their ability for self-assembly into distinct geometries is of scientific interest. At phase boundaries, in solutions and on a variety of surfaces they form different lattice structures. The geometry and arrangement is determined by the C-terminal self assembly-domain, which is specific for each S-layer protein. The most common lattice geometries are oblique, square and hexagonal. By modifying the characteristics of the S-layer through combination with functional groups and protein domains as well as their defined position and orientation to eachother (determined by the S-layer geometry) it is possible to realize various practical applications ([http://onlinelibrary.wiley.com/doi/10.1111/j.1574-6968.2006.00573.x/full Sleytr ''et al.'', 2007]).
 +
 
 +
 
 
===Usage and Biology===
 
===Usage and Biology===
 +
S-layer proteins can be used as scaffold for nanobiotechnological applications and devices by e.g. fusing the S-layer's self-assembly domain to other functional protein domains. It is possible to coat surfaces and liposomes with S-layers. A big advantage of S-layers: after expressing in ''E. coli'' and purification, the nanobiotechnological system is cell-free. This enhances the biological security of a device.
 +
 +
This fluorescent S-layer fusion protein is used to characterize purification methods and the S-layer's ability to self-assemble on surfaces. It is also possible to use the characteristic of mCherry as a pH indicator ([http://pubs.acs.org/doi/abs/10.1021/bm901071b Kainz ''et al.'', 2010]).
 +
 +
 +
===Important parameters===
 +
<center>
 +
{|{{Table}}
 +
!Experiment
 +
!Characteristic
 +
!Result
 +
|-
 +
|rowspan="3"|[[Part:BBa_K525304#Expression_in_E._coli | Expression (''E. coli'')]]
 +
|Localisation
 +
|Inclusion body
 +
|-
 +
|Compatibility
 +
|''E. coli'' KRX and BL21(DE3)
 +
|-
 +
|Induction of expression
 +
|expression of T7 polymerase + IPTG or lactose
 +
|-
 +
|rowspan="3"|Purification
 +
|Molecular weight
 +
|109.9 kDa
 +
|-
 +
|Theoretical pI
 +
|5.70
 +
|-
 +
|Excitation / emission
 +
|587 / 610 nm
 +
|-
 +
|Immobilization behaviour
 +
|Immobilization time
 +
|4 h
 +
|-
 +
|}
 +
</center>
  
 
<!-- -->
 
<!-- -->

Revision as of 18:22, 21 September 2011

Fusion Protein of S-Layer SgsE and mCerulean

Fusion Protein of S-Layer SgsE and mCerulean

S-layers (crystalline bacterial surface layer) are crystal-like layers consisting of multiple protein monomers and can be found in various (archae-)bacteria. They constitute the outermost part of the cell wall. Especially their ability for self-assembly into distinct geometries is of scientific interest. At phase boundaries, in solutions and on a variety of surfaces they form different lattice structures. The geometry and arrangement is determined by the C-terminal self assembly-domain, which is specific for each S-layer protein. The most common lattice geometries are oblique, square and hexagonal. By modifying the characteristics of the S-layer through combination with functional groups and protein domains as well as their defined position and orientation to eachother (determined by the S-layer geometry) it is possible to realize various practical applications ([http://onlinelibrary.wiley.com/doi/10.1111/j.1574-6968.2006.00573.x/full Sleytr et al., 2007]).


Usage and Biology

S-layer proteins can be used as scaffold for nanobiotechnological applications and devices by e.g. fusing the S-layer's self-assembly domain to other functional protein domains. It is possible to coat surfaces and liposomes with S-layers. A big advantage of S-layers: after expressing in E. coli and purification, the nanobiotechnological system is cell-free. This enhances the biological security of a device.

This fluorescent S-layer fusion protein is used to characterize purification methods and the S-layer's ability to self-assemble on surfaces. It is also possible to use the characteristic of mCherry as a pH indicator ([http://pubs.acs.org/doi/abs/10.1021/bm901071b Kainz et al., 2010]).


Important parameters

Experiment Characteristic Result
Expression (E. coli) Localisation Inclusion body
Compatibility E. coli KRX and BL21(DE3)
Induction of expression expression of T7 polymerase + IPTG or lactose
Purification Molecular weight 109.9 kDa
Theoretical pI 5.70
Excitation / emission 587 / 610 nm
Immobilization behaviour Immobilization time 4 h

Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    INCOMPATIBLE WITH RFC[21]
    Illegal BglII site found at 167
    Illegal BglII site found at 1022
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    INCOMPATIBLE WITH RFC[25]
    Illegal NgoMIV site found at 76
    Illegal AgeI site found at 3121
  • 1000
    INCOMPATIBLE WITH RFC[1000]
    Illegal BsaI site found at 1657


Expression in E. coli

The SgsE (K525301) gen was fused with a mCerulean (BBa_J18930) using [http://2011.igem.org/Team:Bielefeld-Germany/Protocols#Gibson_assembly Gibson assembly] for characterization.

The SgsE|mCerulean fusion protein was overexpressed in E. coli KRX after induction of T7 polymerase by supplementation of 0,1 % L-rhamnose and 1 mM IPTG using the [http://2011.igem.org/Team:Bielefeld-Germany/Protocols/Downstream-processing#Expression_of_S-layer_genes_in_E._coli autinduction protocol] from promega.

Figure 1: Growthcurve of E. coli KRX expressing the fusion protein of Sgse and mCerluean with and without induction. A curve depicting KRX wildtype is shown for comparsion.
Figure 2: RFU to OD600 ratio of E. coli KRX expressing the fusion protein of Sgse and mCerulean with and without induction. A curve depicting KRX wildtype is shown for comparsion.