I am curious to know the indigenous NDP-sugars(UDP-D-glucose and TDP-L-rhamnose) in E. coli BL21 (DE3) are in alpha- or beta- configuration. Since it is important to know for the sterio-selective characterization of a glycosyltransferase.
Dear Prakash,
In all naturally occcuring nucleotide sugars (except CMP-Sia and CMP-KDO), the sugar residue is alpha-linked to the nucleotide moiety. Consequently, most inverting glycosyltransferases produce beta-linked glycoconjugates, while retaining ones, conversely, synthesize alpha-linked products.
Good luck with your study!
Kind regards,
Radek
http://www.ncbi.nlm.nih.gov/books/NBK1921/
Dear Radek,
Thank you for your answer and the linked reference. I appreciate your answer regardless of the glycosyltransferase properties. But when I look at the Kegg database, It shows different result. Since we refer this large database for most of the metabolic pathway studies and many more, but it shows the UDP-D-glucose in alpha- configuration while dTDP-L-rhamnose in beta- configuration in case of E. coli BL21 (DE3).
http://www.genome.jp/dbget-bin/www_bget?C00029
http://www.genome.jp/dbget-bin/www_bget?C03319
Dear Prakash,
Thank you for sharing these search results, interesting indeed. Apparently both alpha- and beta-linked TDP-rhamnose may be produced and used, even by different E. coli strains. I would double check though, because it is not very uncommon to stumble upon errors in databases.
Kind regards,
Radek
In BL21 you will find UDP-alpha-D-glucose:
https://biocyc.org/ECOLI/NEW-IMAGE?type=PATHWAY&object=PWY-7343&detail-level=3
and TDP-beta-L-Rhamnose:
https://biocyc.org/META/new-image?object=DTDPRHAMSYN-PWY
- Badges
- Science method