Part:BBa_K4428000

N-terminal domain of BclB anchor protein

Several anchoring motifs have been used for the surface display of proteins in E. coli. However, most of them suffer from the limitation of expressing only small peptides and proteins on the cell surface. To overcome this, heterologous anchoring motifs have been used. One such motif is BclB from B. anthracis.

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]

Background

BclB is a collagen-like glycoprotein found in the outermost layer of the B. anthracis spore called exosporium. This glycoprotein is incorporated into the exosporium by the action of certain sequences near the N-terminal region of the BclB glycoproteins (Waller et al 2005). BclB was found to play a role in the structural integrity of the exosporium. The influence of BclB on the incorporation of the BclA protein and on the overall architecture of the spore, directly or indirectly, is one of the keys to the formation or maintenance of a rigid and complete exosporium structure in B. anthracis. BclB is a 28 amino acid sequence, which contains a repeated GXX motif, GITGVTGAT called the BclB repeat, which is thought to be responsible for it’s rigid binding to the cell surface (B.M.Thompson et al 2007).

Part Uses

BclB as an anchoring motif has been previously used by Srivastava et al 2018, for the surface display of Dibenzothiophene monooxygenase on the recombinant E.coli. In this project, the N terminus of BclB was used as an anchoring motif to hold the lead-binding proteins on the surface of the engineered bacteria, so that these proteins can bind specifically to Lead ions and hence can be used for lead removal. BclB can be used as an anchoring protein for proteins to be expressed on the cellular surface of E. coli.

References

[1] Waller LN, Stump MJ, Fox KF, Harley WM, Fox A, Stewart GC, Shahgholi M. Identification of a second collagen-like glycoprotein produced by Bacillus anthracis and demonstration of associated spore-specific sugars. J Bacteriol. 2005 Jul;187(13):4592-7.
[2] Thompson BM, Waller LN, Fox KF, Fox A, Stewart GC. The BclB glycoprotein of Bacillus anthracis is involved in exosporium integrity. J Bacteriol. 2007 Sep;189(18):6704-13.
[3] Rangra, S., Kabra, M., Gupta, V., & Srivastava, P. (2018). Improved conversion of Dibenzothiophene into sulfone by surface display of Dibenzothiophene monooxygenase (DszC) in recombinant Escherichia coli. Journal of Biotechnology.