Latest revision as of 00:16, 28 October 2020

bcsB-Regulatory Subunit of Bacterial Cellulose operon

This part codes for the BscB protein, the regulatory subunit of the cellulose synthase in Bacteria. It is codon optimised for Flavobacterium johnsoniae UW101

Description

bcsB codes for BcsB, the regulatory subunit of the cellulose synthase. BcsB binds to c-di-GMP, which afterwards aids the activation of the cellulose synthesis process. This CDS originates from a very productive cellulose synthesising bacterium, Komagataeibacter xylinus (GenBank Acc. No. X54676.1).

Protein Analysis

BcsB is a large periplasmic protein that is anchored to the inner membrane via a single C-terminal transmembrane helix. BcsB may guide the polymer across the periplasm toward the outer membrane via two carbohydrate-binding domains (CBDs). BcsB is crucial for the catalytic activity of BcsA and is localized in the region required for cellulose synthesis within BcsB’s C-terminal, a membrane-associated domain that packs against the transmembrane region of BcsA.

The Bacterial Bcs Operon

The putative operon consists of four genes, bcsA, bcsB, bcsC and bcsD. It encodes membrane-associated proteins can catalyse extracellular Bacterial Cellulose synthesis in vivo. Once the bcsABCD operon expression is triggered, BcsA and BcsB proteins form the BcsAB complex, which binds its substrate, UDP-glucose, at an intracellular glycosyltransferase (GT) domain. This complec is the active core of the cellulose synthase. This is followed by the secretion of BC fibres through pores and passageways formed by BcsC and BcsD proteins. Co expression with Cmcax and CcpAx have shown increased production. The cellulose synthase, BcsC, BcsD, Cmcax, and CcpAx are the biocatalysts of UDP-glucose transformation to cellulose. Two main applications of cellulose in biosciences are scaffolds for tissue engineering and generally in biomedicine.

Athens 2020

The current part is designed by iGEM Athens 2020 team during the project MORPHÆ. In this project, Flavobacteria were used to produce a non-cellular structurally coloured biomaterial which would require the secretion of a biomolecule that Flavobacteria do not normally secrete. Our hypothesis is that the formed matrix will have a structure similar to that of the biofilm and thus, it will provide the material with macroscopically the same colouration properties as the biofilm.

SOURCE OF THIS PART

The nucleotide sequences of the bacterial cellulose operon come from the strain Komagataeibacter xylinus and GenBank database (Acc.No.X54676.1). K.xylinus is a member of the acetic acid bacteria, a group of Gram-negative aerobic bacteria that produce acetic acid during fermentation.

Useful Links:

NCBI taxonomy:

https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=28448&lvl=3&lin=f&keep=1&srchmode=1&unlock

GenBank link:

https://www.ncbi.nlm.nih.gov/nuccore/X54676.1

Codon optimisation bank:

http://genomes.urv.es/OPTIMIZER/?fbclid=IwAR0ALbP_C8UVY4itvYdNX8b5KYYUM5ulQojz8UJAK6Zj5llobNNxE-jYmXQ

Codon optimization table:

https://www.kazusa.or.jp/codon/cgi-bin/showcodon.cgi?species=376686&fbclid=IwAR0gwwrIarZsiYhWvHPc2BKy-iB_2OM-DPB5I2HYJZwBNiasmlLXWK87PwM

REFERENCES

Braun, T., Khubbar, M., Saffarini, D., & McBride, M. (2005). Flavobacterium johnsoniae Gliding Motility Genes Identified by mariner Mutagenesis. Journal Of Bacteriology, 187(20), 6943-6952. doi: 10.1128/jb.187.20.6943-6952.2005

Buldum, G., Bismarck, A., & Mantalaris, A. (2017). Recombinant biosynthesis of bacterial cellulose in genetically modified Escherichia coli. Bioprocess And Biosystems Engineering, 41(2), 265-279. doi: 10.1007/s00449-017-1864-1

Johansen, V., Catón, L., Hamidjaja, R., Oosterink, E., Wilts, B., & Rasmussen, T. et al. (2018). Genetic manipulation of structural color in bacterial colonies. Proceedings Of The National Academy Of Sciences, 115(11), 2652-2657. doi: 10.1073/pnas.1716214115

McBride, M., & Kempf, M. (1996). Development of techniques for the genetic manipulation of the gliding bacterium Cytophaga johnsonae. Journal Of Bacteriology, 178(3), 583-590. doi: 10.1128/jb.178.3.583-590.1996

Nakamura, Y. (2000). Codon usage tabulated from international DNA sequence databases: status for the year 2000. Nucleic Acids Research, 28(1), 292-292. doi: 10.1093/nar/28.1.292

Omadjela, O., Narahari, A., Strumillo, J., Melida, H., Mazur, O., Bulone, V., & Zimmer, J. (2013). BcsA and BcsB form the catalytically active core of bacterial cellulose synthase sufficient for in vitro cellulose synthesis. Proceedings Of The National Academy Of Sciences, 110(44), 17856-17861. doi: 10.1073/pnas.1314063110

Römling, U., & Galperin, M. (2015). Bacterial cellulose biosynthesis: diversity of operons, subunits, products, and functions. Trends In Microbiology, 23(9), 545-557. doi: 10.1016/j.tim.2015.05.005