Title : Recombinant human
interleukin-12 is the second example of a
C-mannosylated protein
Abstract :
- The beta- chain of human interleukin 12 ( IL-12 ) contains at position 319-322, the sequence Trp-x-x- Trp
- In human RNase 2 this is the recognition motif for a new, recently discovered posttranslational modification, i.e., the C-glycosidic attachment of a mannosyl residue to the side chain of tryptophan
- Analysis of C-terminal peptides of recombinant IL-12 ( rHuIL-12 ) by mass spectrometry and NMR spectroscopy revealed that Trp-319beta is (partially) C-mannosylated
- This finding was extended by in vitro mannosylation experiments, using a synthetic peptide derived from the same region of the protein as an acceptor
- Furthermore, human B-lymphoblastoid cells, which secrete IL-12 , were found to contain an enzyme that carries out the C-mannosylation reaction
- This shows that nonrecombinant IL-12 is potentially C-mannosylated as well
- This is only the second report on a C-mannosylated protein
- However, the occurrence of the C-mannosyltransferase activity in a variety of cells and tissues, and the presence of the recognition motif in many proteins indicate that more C-mannosylated proteins may be found
Output (sent_index, trigger,
protein,
sugar,
site):
- 0. C-mannosylated, , protein, -, -
- 3. C-mannosylated, , -, -, Trp
- 6. C-mannosylated, , IL-12, -, -
- 7. C-mannosylated, , protein, -, -
- 8. C-mannosylated, , proteins, -, -
Output(Part-Of) (sent_index,
protein,
site):
- 2. RNase 2, motif
- 3. IL-12, peptides
- 4. protein, region
*Output_Site_Fusion* (sent_index,
protein,
sugar,
site):