Q96V44 · LAD_HYPJE
- ProteinL-arabinitol 4-dehydrogenase
- Genelad1
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids377 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Catalyzes the NAD-dependent oxidation of L-arabinitol to L-xylulose in the fungal L-arabinose catabolic pathway. L-arabinose catabolism is important for using plant material as a carbon source. Can partially compensate for xylitol dehydrogenase in xdh1 mutants. Also oxidizes galactitol to L-xylo-3-hexulose as an alternative to the standard Leloir pathway for D-galactose metabolism. NADP cannot act as a cosubstrate.
Catalytic activity
- L-arabinitol + NAD+ = H+ + L-xylulose + NADH
Cofactor
Note: Binds 2 Zn2+ ions per subunit.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
18 mM | L-arabinitol | 7 | ||||
200 mM | xylitol | 7 | ||||
4.5 mM | L-arabinitol | 8.6 | ||||
25 mM | D-talitol | 8.6 | ||||
60 mM | galactitol | 8.6 | ||||
46 mM | D-sorbitol | 8.6 | ||||
11.3 mM | D-allitol | 8.6 | ||||
37 mM | L-mannitol | 8.6 | ||||
191 mM | L-iditol | 8.6 | ||||
580 mM | D-arabino-3-hexulose | 8.6 | ||||
81 mM | L-xylo-3-hexulose | 8.6 | ||||
96 mM | D-fructose | 8.6 | ||||
81 mM | D-psicose | 8.6 | ||||
19 mM | L-sorbitol | 8.6 | ||||
28 mM | L-tagatose | 8.6 | ||||
115 mM | D-sorbose | 8.6 | ||||
180 μM | NAD | 7 |
Vmax | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|
27 nmol/sec/mg | 9 | with L-arabinitol as substrate, 10 | |||
10 nmol/sec/mg | 7 | with L-arabinitol as substrate | |||
6 nmol/sec/mg | 7 | with xylitol as substrate | |||
0.213 nmol/sec/mg | 8.6 | with L-arabinitol as substrate | |||
0.146 nmol/sec/mg | 8.6 | with D-talitol as substrate | |||
0.012 nmol/sec/mg | 8.6 | with galactitol as substrate | |||
0.034 nmol/sec/mg | 8.6 | with D-sorbitol as substrate | |||
0.008 nmol/sec/mg | 8.6 | with D-allitol as substrate | |||
0.027 nmol/sec/mg | 8.6 | with L-mannitol as substrate | |||
0.021 nmol/sec/mg | 8.6 | with L-iditol as substrate | |||
0.969 nmol/sec/mg | 8.6 | with D-arabino-3-hexulose as substrate | |||
0.197 nmol/sec/mg | 8.6 | with L-xylo-3-hexulose as substrate | |||
0.008 nmol/sec/mg | 8.6 | with D-fructose as substrate | |||
0.011 nmol/sec/mg | 8.6 | with D-psicose as substrate | |||
0.001 nmol/sec/mg | 8.6 | with L-sorbitol as substrate | |||
0.003 nmol/sec/mg | 8.6 | with L-tagatose as substrate | |||
0.001 nmol/sec/mg | 8.6 | with D-sorbose as substrate |
pH Dependence
Optimum pH is 9.4. Active from pH 7 to pH 11.
Temperature Dependence
Optimum temperature is 55-65 degrees Celsius.
Pathway
Carbohydrate degradation; L-arabinose degradation via L-arabinitol; D-xylulose 5-phosphate from L-arabinose (fungal route): step 2/5.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 66 | Zn2+ 1 (UniProtKB | ChEBI); catalytic | ||||
Sequence: C | ||||||
Binding site | 91 | Zn2+ 1 (UniProtKB | ChEBI); catalytic | ||||
Sequence: H | ||||||
Binding site | 92 | Zn2+ 1 (UniProtKB | ChEBI); catalytic | ||||
Sequence: E | ||||||
Binding site | 121 | Zn2+ 2 (UniProtKB | ChEBI); structural | ||||
Sequence: C | ||||||
Binding site | 124 | Zn2+ 2 (UniProtKB | ChEBI); structural | ||||
Sequence: C | ||||||
Binding site | 127 | Zn2+ 2 (UniProtKB | ChEBI); structural | ||||
Sequence: C | ||||||
Binding site | 135 | Zn2+ 2 (UniProtKB | ChEBI); structural | ||||
Sequence: C | ||||||
Binding site | 176 | Zn2+ 1 (UniProtKB | ChEBI); catalytic | ||||
Sequence: E | ||||||
Binding site | 203-204 | NAD+ (UniProtKB | ChEBI) | ||||
Sequence: PI | ||||||
Binding site | 224 | NAD+ (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 229 | NAD+ (UniProtKB | ChEBI) | ||||
Sequence: R | ||||||
Binding site | 296 | NAD+ (UniProtKB | ChEBI) | ||||
Sequence: I | ||||||
Binding site | 320-322 | NAD+ (UniProtKB | ChEBI) | ||||
Sequence: QYR |
GO annotations
Aspect | Term | |
---|---|---|
Molecular Function | L-arabinitol 4-dehydrogenase activity | |
Molecular Function | metal ion binding | |
Biological Process | arabinose catabolic process | |
Biological Process | D-xylose catabolic process | |
Biological Process | galactose catabolic process | |
Biological Process | L-arabinose catabolic process to xylulose 5-phosphate |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameL-arabinitol 4-dehydrogenase
- EC number
- Short namesLAD
Gene names
Organism names
- Strains
- Taxonomic lineageEukaryota > Fungi > Dikarya > Ascomycota > Pezizomycotina > Sordariomycetes > Hypocreomycetidae > Hypocreales > Hypocreaceae > Trichoderma
Accessions
- Primary accessionQ96V44
Organism-specific databases
Phenotypes & Variants
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 224-225 | Alters cofactor specificity from NAD to NADP; when associated with T-362. | ||||
Sequence: DI → SR | ||||||
Mutagenesis | 362 | Alters cofactor specificity from NAD to NADP; when associated with 224-SR-225. | ||||
Sequence: A → T |
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000418403 | 1-377 | L-arabinitol 4-dehydrogenase | |||
Sequence: MSPSAVDDAPKATGAAISVKPNIGVFTNPKHDLWISEAEPSADAVKSGADLKPGEVTIAVRSTGICGSDVHFWHAGCIGPMIVEGDHILGHESAGEVIAVHPTVSSLQIGDRVAIEPNIICNACEPCLTGRYNGCEKVEFLSTPPVPGLLRRYVNHPAVWCHKIGNMSWENGALLEPLSVALAGMQRAKVQLGDPVLVCGAGPIGLVSMLCAAAAGACPLVITDISESRLAFAKEICPRVTTHRIEIGKSAEETAKSIVSSFGGVEPAVTLECTGVESSIAAAIWASKFGGKVFVIGVGKNEISIPFMRASVREVDIQLQYRYSNTWPRAIRLIESGVIDLSKFVTHRFPLEDAVKAFETSADPKSGAIKVMIQSLD |
Post-translational modification
The N-terminus is blocked.
Expression
Induction
Only expressed when grown on L-arabinose.
Interaction
Subunit
Homotetramer.
Structure
Sequence
- Sequence statusComplete
- Length377
- Mass (Da)39,886
- Last updated2001-12-01 v1
- Checksum5015D4A61D948D1D
Keywords
- Technical term