S3DB74 · GLOI_GLAL2
- Protein3-isopropylmalate dehydrogenase gloI
- GenegloI
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids373 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score4/5
Function
function
3-isopropylmalate dehydrogenase; part of the gene cluster that mediates the biosynthesis of pneumocandins, lipohexapeptides of the echinocandin family that prevent fungal cell wall formation by non-competitive inhibition of beta-1,3-glucan synthase (PubMed:27705900).
The 10,12-dimethylmyristoyl side chain is synthesized by the reducing polyketide synthase gloL/GLPKS4 (PubMed:27494047).
The thioesterase gloN/GLHYD exclusively interacts with gloL/GLPKS4 to maintain turnover of the polyketide side chain (PubMed:27494047).
The 10R,12S-dimethylmyristic acid is then transferred to the first thiolation domain of the nonribosomal peptide synthetase gloA/GLNRPS4 by the acyl-AMP ligase gloD/GLligase, followed by its acylation to L-ornithine to trigger elongation of the cyclic hexapeptide (PubMed:27494047).
L-ornithine, 4R-hydroxyl-L-proline (generated from L-proline by the dioxygenase gloF/GLOXY2), 3S-hydroxyl-L-homotyrosine (generated by gloG/GLHtyB, gloH/GLHtyA, gloI/GLHtyC, gloJ/GLHtyD and hydroxylated at C-3 by the dioxygenase gloM/GLOXY1), 3R-hydroxyl-L-glutamine (generated from L-glutamine probably by the dioxygenase gloE/GLOXY3) and 3S-hydroxyl-L-proline (generated from L-proline by the dioxygenase gloF/GLOXY2 to yield pneumocandin B0), or 3S-hydroxyl-4S-methyl-L-proline (generated from L-leucine by the dioxygenase gloC/GLOXY4 to yield pneumocandin A0) are sequentially added to the growing chain (PubMed:25270390, PubMed:25527531, PubMed:25879325).
The last C domain of gloA/GLNRPS4 is proposed to be responsible for cyclization by condensation to form the peptide bond between L-ornithine and 3S-hydroxyl-4S-methyl-L-proline (for pneumocandin A0) or 3S-hydroxyl-L-proline (for pneumocandin B0). Finally, the subsequent C-4 hydroxylation of 3S-hydroxyl-L-homotyrosine and L-ornithine dihydroxylation at C-4 and C-5 are performed by the cytochrome P450 monooxygenases gloP/GLP450-1 and gloO/GLP450-2, respectively (PubMed:25879325).
The 10,12-dimethylmyristoyl side chain is synthesized by the reducing polyketide synthase gloL/GLPKS4 (PubMed:27494047).
The thioesterase gloN/GLHYD exclusively interacts with gloL/GLPKS4 to maintain turnover of the polyketide side chain (PubMed:27494047).
The 10R,12S-dimethylmyristic acid is then transferred to the first thiolation domain of the nonribosomal peptide synthetase gloA/GLNRPS4 by the acyl-AMP ligase gloD/GLligase, followed by its acylation to L-ornithine to trigger elongation of the cyclic hexapeptide (PubMed:27494047).
L-ornithine, 4R-hydroxyl-L-proline (generated from L-proline by the dioxygenase gloF/GLOXY2), 3S-hydroxyl-L-homotyrosine (generated by gloG/GLHtyB, gloH/GLHtyA, gloI/GLHtyC, gloJ/GLHtyD and hydroxylated at C-3 by the dioxygenase gloM/GLOXY1), 3R-hydroxyl-L-glutamine (generated from L-glutamine probably by the dioxygenase gloE/GLOXY3) and 3S-hydroxyl-L-proline (generated from L-proline by the dioxygenase gloF/GLOXY2 to yield pneumocandin B0), or 3S-hydroxyl-4S-methyl-L-proline (generated from L-leucine by the dioxygenase gloC/GLOXY4 to yield pneumocandin A0) are sequentially added to the growing chain (PubMed:25270390, PubMed:25527531, PubMed:25879325).
The last C domain of gloA/GLNRPS4 is proposed to be responsible for cyclization by condensation to form the peptide bond between L-ornithine and 3S-hydroxyl-4S-methyl-L-proline (for pneumocandin A0) or 3S-hydroxyl-L-proline (for pneumocandin B0). Finally, the subsequent C-4 hydroxylation of 3S-hydroxyl-L-homotyrosine and L-ornithine dihydroxylation at C-4 and C-5 are performed by the cytochrome P450 monooxygenases gloP/GLP450-1 and gloO/GLP450-2, respectively (PubMed:25879325).
Catalytic activity
- (2R,3S)-3-isopropylmalate + NAD+ = 4-methyl-2-oxopentanoate + CO2 + NADH
Cofactor
Mn2+ (UniProtKB | Rhea| CHEBI:29035 )
Note: Binds 1 Mg2+ or Mn2+ ion per subunit.
Biotechnology
Pneumocandin B0 is the starting molecule for the first semisynthetic echinocandin antifungal drug, caspofungin acetate (PubMed:25527531).
Pneumocandin B0 is a minor fermentation product, and its industrial production was achieved by a combination of extensive mutation and medium optimization (PubMed:25527531).
Inactivation of three of gloP/GLP450-1, gloO/GLP450-2, and gloM/GLOXY1 generates 13 different pneumocandin analogs that lack one, two, three, or four hydroxyl groups on 4R,5R-dihydroxy-ornithine and 3S,4S-dihydroxy-homotyrosine of the parent hexapeptide (PubMed:25879325).
All of these cyclic lipopeptides show potent antifungal activities, and two new metabolites pneumocandins F and G are more potent in vitro against Candida species and Aspergillus fumigatus than the principal fermentation products, pneumocandins A0 and B0 (PubMed:25879325).
Moreover, feeding alternative side chain precursors yields acrophiarin and 4 additional pneumocandin congeners with straight C14, C15, and C16 side chains. One of those compounds, pneumocandin I, has elevated antifungal activity and similar hemolytic activity compared to pneumocandin B0, the starting molecule for caspofungin, demonstrating the potential for using gloD/GLligase for future engineering of new echinocandin analogs (PubMed:27494047).
Pneumocandin B0 is a minor fermentation product, and its industrial production was achieved by a combination of extensive mutation and medium optimization (PubMed:25527531).
Inactivation of three of gloP/GLP450-1, gloO/GLP450-2, and gloM/GLOXY1 generates 13 different pneumocandin analogs that lack one, two, three, or four hydroxyl groups on 4R,5R-dihydroxy-ornithine and 3S,4S-dihydroxy-homotyrosine of the parent hexapeptide (PubMed:25879325).
All of these cyclic lipopeptides show potent antifungal activities, and two new metabolites pneumocandins F and G are more potent in vitro against Candida species and Aspergillus fumigatus than the principal fermentation products, pneumocandins A0 and B0 (PubMed:25879325).
Moreover, feeding alternative side chain precursors yields acrophiarin and 4 additional pneumocandin congeners with straight C14, C15, and C16 side chains. One of those compounds, pneumocandin I, has elevated antifungal activity and similar hemolytic activity compared to pneumocandin B0, the starting molecule for caspofungin, demonstrating the potential for using gloD/GLligase for future engineering of new echinocandin analogs (PubMed:27494047).
Pathway
Mycotoxin biosynthesis.
Features
Showing features for binding site, site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 92 | substrate | ||||
Sequence: S | ||||||
Binding site | 98 | substrate | ||||
Sequence: R | ||||||
Binding site | 108 | substrate | ||||
Sequence: R | ||||||
Site | 194 | Critical for catalysis | ||||
Sequence: K | ||||||
Binding site | 228 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 253 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 257 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 294-300 | NADP+ (UniProtKB | ChEBI) | ||||
Sequence: HGSAPDI | ||||||
Binding site | 307 | NADP+ (UniProtKB | ChEBI) | ||||
Sequence: N |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | cytosol | |
Molecular Function | 3-isopropylmalate dehydrogenase activity | |
Molecular Function | magnesium ion binding | |
Molecular Function | NAD binding | |
Biological Process | L-leucine biosynthetic process |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended name3-isopropylmalate dehydrogenase gloI
- EC number
- Alternative names
Gene names
Organism names
- Strain
- Taxonomic lineageEukaryota > Fungi > Dikarya > Ascomycota > Pezizomycotina > Leotiomycetes > Helotiales > Helotiaceae > Glarea
Accessions
- Primary accessionS3DB74
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Phenotypes & Variants
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000444494 | 1-373 | 3-isopropylmalate dehydrogenase gloI | |||
Sequence: MTKQFDIVVFPGDYGGPEVMAEGIKVLKAIERKHQSDVSFNLKYHLIGGASFDIHDTPITTEALEDAKAASAVLLGAVGGPKWDGTPVPVESGLGRLRKFLDAFGNIRPVNFIAPSLVNCSSFKEHVVSGTDITIVRELTGGIYFGARQEHDGSFNSASDLDHYDRDSIVRAARLAGKLAMSRQPHLPVTSLDKANLLAACGRLWRGVVKEVFETEFPTIKLSHMLIDTAAMNVARRPTSLNGIILTSNMFGDIISDEASAIPGSLGLLPSASLCAIPTVLDASKVRGIYEPIHGSAPDIAGQGIINPTGMILSVAMMLRYSLAMPEAADSIEAAVGKVIEDDCRTSDIGGRASTADFGDAVVIALRNCLDKN |
Interaction
Structure
Sequence
- Sequence statusComplete
- Length373
- Mass (Da)39,688
- Last updated2013-09-18 v1
- ChecksumC53AD268B13A704E
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
KE145356 EMBL· GenBank· DDBJ | EPE34344.1 EMBL· GenBank· DDBJ | Genomic DNA |