English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

A bioinformatics study revealed that  Mycobacterium tuberculosis  H37Rv (Mtb) contains sequence homologs of  Campylobacter jejuni  protein glycosylation enzymes. The ORF  Rv3634c  from Mtb was identified as a sequence homolog of  C .  jejuni  UDP-Gal/GalNAc 4-epimerase. This study reports the cloning of  Rv3634c  and its expression as an N-terminal His-tagged protein. The recombinant protein was shown to have UDP-Gal/Glc 4-epimerase activity by GOD-POD assay and by reverse phase HPLC. This enzyme was shown to have UDP-GalNAc 4-epimerase activity also. Residues Ser121, Tyr146 and Lys150 were shown by site-directed mutagenesis to be important for enzyme activity. Mutation of Ser121 and Tyr146 to Ala and Phe, respectively, led to complete loss of activity whereas mutation of Lys150 to Arg led to partial loss of activity. There were no gross changes in the secondary structures of any of these three mutants. These results suggest that Ser121 and Tyr146 are essential for epimerase activity of Rv3634c. UDP-Gal/Glc 4-epimerases from other organisms also have a catalytic triad consisting of Ser, Tyr and Lys. The triad carries out proton transfer from nucleotide sugar to NAD +  and back, thus effecting the epimerization of the substrate. Addition of NAD +  to Lys150 significantly abrogates the loss of activity, suggesting that, as in other epimerases, NAD +  is associated with Rv3634c.

Rv3634c from Mycobacterium tuberculosis H37Rv encodes an enzyme with UDP-Gal/Glc and UDP-GalNAc 4-epimerase activities