Reaction participants Show >> << Hide
- Name help_outline 3,3'-di-O-methyl-4α-mannobiose Identifier CHEBI:145745 Charge 0 Formula C14H26O11 InChIKeyhelp_outline VHPIGROAJWTJIW-NKTQMSGFSA-N SMILEShelp_outline [C@H]1([C@H]([C@H]([C@@H]([C@H](O1)CO)O[C@@H]2[C@H]([C@H]([C@@H]([C@H](O2)CO)O)OC)O)OC)O)O 2D coordinates Mol file for the small molecule Search links Involved in 1 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline S-adenosyl-L-methionine Identifier CHEBI:59789 Charge 1 Formula C15H23N6O5S InChIKeyhelp_outline MEFKEPWMEQBLKI-AIRLBKTGSA-O SMILEShelp_outline C[S+](CC[C@H]([NH3+])C([O-])=O)C[C@H]1O[C@H]([C@H](O)[C@@H]1O)n1cnc2c(N)ncnc12 2D coordinates Mol file for the small molecule Search links Involved in 904 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline 1,3,3'-tri-O-methyl-4α-mannobiose Identifier CHEBI:145746 Charge 0 Formula C15H28O11 InChIKeyhelp_outline GJVGVCRJQPOURF-AAYHEAFJSA-N SMILEShelp_outline [C@H]1([C@H]([C@H]([C@@H]([C@H](O1)CO)O[C@H]2[C@H]([C@H]([C@@H]([C@H](O2)CO)O)OC)O)OC)O)OC 2D coordinates Mol file for the small molecule Search links Involved in 1 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline S-adenosyl-L-homocysteine Identifier CHEBI:57856 Charge 0 Formula C14H20N6O5S InChIKeyhelp_outline ZJUKTBDSGOFHSH-WFMPWKQPSA-N SMILEShelp_outline Nc1ncnc2n(cnc12)[C@@H]1O[C@H](CSCC[C@H]([NH3+])C([O-])=O)[C@@H](O)[C@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 827 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline H+ Identifier CHEBI:15378 Charge 1 Formula H InChIKeyhelp_outline GPRLSGONYQIRFK-UHFFFAOYSA-N SMILEShelp_outline [H+] 2D coordinates Mol file for the small molecule Search links Involved in 9,521 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Cross-references
| RHEA:62408 | RHEA:62409 | RHEA:62410 | RHEA:62411 | |
|---|---|---|---|---|
| Reaction direction help_outline | undefined | left-to-right | right-to-left | bidirectional |
| UniProtKB help_outline |
|
|||
| EC numbers help_outline | ||||
| KEGG help_outline | ||||
| MetaCyc help_outline |
Publications
-
Biosynthesis of mycobacterial methylmannose polysaccharides requires a unique 1-O-methyltransferase specific for 3-O-methylated mannosides.
Ripoll-Rozada J., Costa M., Manso J.A., Maranha A., Miranda V., Sequeira A., Ventura M.R., Macedo-Ribeiro S., Pereira P.J.B., Empadinhas N.
Mycobacteria are a wide group of organisms that includes strict pathogens, such as <i>Mycobacterium tuberculosis</i>, as well as environmental species known as nontuberculous mycobacteria (NTM), some of which-namely <i>Mycobacterium avium</i>-are important opportunistic pathogens. In addition to a ... >> More
Mycobacteria are a wide group of organisms that includes strict pathogens, such as <i>Mycobacterium tuberculosis</i>, as well as environmental species known as nontuberculous mycobacteria (NTM), some of which-namely <i>Mycobacterium avium</i>-are important opportunistic pathogens. In addition to a distinctive cell envelope mediating critical interactions with the host immune system and largely responsible for their formidable resistance to antimicrobials, mycobacteria synthesize rare intracellular polymethylated polysaccharides implicated in the modulation of fatty acid metabolism, thus critical players in cell envelope assembly. These are the 6-<i>O</i>-methylglucose lipopolysaccharides (MGLP) ubiquitously detected across the <i>Mycobacterium</i> genus, and the 3-<i>O</i>-methylmannose polysaccharides (MMP) identified only in NTM. The polymethylated nature of these polysaccharides renders the intervening methyltransferases essential for their optimal function. Although the knowledge of MGLP biogenesis is greater than that of MMP biosynthesis, the methyltransferases of both pathways remain uncharacterized. Here, we report the identification and characterization of a unique <i>S</i>-adenosyl-l-methionine-dependent sugar 1-<i>O</i>-methyltransferase (MeT1) from <i>Mycobacterium hassiacum</i> that specifically blocks the 1-OH position of 3,3'-di-<i>O</i>-methyl-4α-mannobiose, a probable early precursor of MMP, which we chemically synthesized. The high-resolution 3D structure of MeT1 in complex with its exhausted cofactor, <i>S</i>-adenosyl-l-homocysteine, together with mutagenesis studies and molecular docking simulations, unveiled the enzyme's reaction mechanism. The functional and structural properties of this unique sugar methyltransferase further our knowledge of MMP biosynthesis and provide important tools to dissect the role of MMP in NTM physiology and resilience. << Less
Proc. Natl. Acad. Sci. U.S.A. 116:835-844(2019) [PubMed] [EuropePMC]