Part:BBa_I750016

Gas Vesicle polycistonic gene

This 6 kbp part contains 11 open reading frames coding for gas vesicle genes (gvpB,R,N,F,G,L,S,K,J,T and U) from Bacillus megaterium VT1660 AF053765. Promotion of the sequence results in expression of gas vesicles, organelles made entirely out of protein. These organelles contain gas and therefore provide bouyancy to the cell. This slows the rate of settling of the cells in Saline. For more info on gas vesicles, see [http://www.ncbi.nlm.nih.gov/pubmed/8177173 Walsby 1994].

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 334
  Illegal BamHI site found at 4139
  Illegal XhoI site found at 3827
  
• 23
  COMPATIBLE WITH RFC[23]
• 25
  INCOMPATIBLE WITH RFC[25]

  Illegal NgoMIV site found at 785
  Illegal NgoMIV site found at 1187
  Illegal AgeI site found at 4106
  
• 1000
  INCOMPATIBLE WITH RFC[1000]

  Illegal SapI.rc site found at 2597
  Illegal SapI.rc site found at 3753
  

Buoyancy Tests

Both [http://2007.igem.org/Melbourne/Lab_GV_Notebook Melbourne 2007] and [http://2009.igem.org/Team:Groningen/Project/Vesicle Groningen 2009] have done buoyancy tests. These tests show that cells containing a plasmid with the GVP gene cluster on it settle more slowly in saline.

Electron Micrograph of Gas Vesicles in E.coli protoplasts

When BBa_K190033, the GVP cluster with an arsenic sensitive promoter (BBa_K190015) in front of it, is introduced in E.coli gas vesicles can be seen under the electron microscope (Figure 1).

Fig. 1: Gas vesicles in E. coli protoplasts (BBa_K190033). The cells were treated with Lysozyme and SDS to create the protoplasts, uranyl acetate was used for staining. Magnification: 11500x. ([http://2009.igem.org/Team:Groningen Groningen 2009])

Further references

The transfer of the GVP gene cluster to E. coli was done first by Ning Li and Maura C. Cannon:
Ning Li and Maura C. Cannon (May 1998). "Gas Vesicle Genes Identified in Bacillus megaterium and Functional Expression in Escherichia coli". Journal of Bacteriology 180(9): 2450–2458.