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Gene ispH from Helicobacter pylori 26695: 4-hydroxy-3-methylbut-2-enyl diphosphate reductase
Member of NCBI Protein Clusters PRK01045(See COMBREX Page ) (See NCBI page)
NCBI Entrez GeneID 898887
UniProtKB accession
RefSeq Protein accession NP_207198.1 (PROVISIONAL)
Gene Symbol(s)
  • symbol: ispH
  • locus tag: HP0400
  • aliases: lytB
Organism Helicobacter pylori 26695 (NCBI TaxID: 85962)
Other Cross References:
  • S
    Structure(s) available in PDB:
  • C
    Gene cloned by a participant in the Protein Structure Initiative (PSI): TargetDB. (To obtain a clone, please contact the PSI:Biology-Materials Repository.)
  • U
    Protein purified by a participant in the Protein Structure Initiative (PSI): TargetDB. (If you are interested in collaborating to obtain the protein, please contact the Northeast Structural Genomics consortium).
  • Protein described in EcoCyc:
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Post a comment about this gene to appear on this page (info).
Source Predicted function(s)
NCBI Protein Cluster Prediction 4-hydroxy-3-methylbut-2-enyl diphosphate reductase
Prof. Vitkup / Confidence:0.89 (References: 19935659, 16507154)
Berkeley Phylogenomics Group GO:0005515 protein binding / (References: 19435885)
Berkeley Phylogenomics Group GO:0051745 4-hydroxy-3-methylbut-2-en-1-yl diphosphate reductase activity / (References: 19435885)
Berkeley Phylogenomics Group GO:0046429 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase activity / (References: 19435885)
Berkeley Phylogenomics Group GO:0042380 hydroxymethylbutenyl pyrophosphate reductase activity / (References: 19435885)
Functional Status blueblue (function predicted, no experimental evidence)
Source of prediction NCBI Protein Clusters info
EC number
BLASTP hits to experimentally validated proteins
green lytB from Aquifex aeolicus VF5
(%_identity=41.84; E_val=1e-60; BitScore=228.0)

other hits with E-value < 1e-05
Share the same Pfam domain composition with the following experimentally validated proteins
green lytB from Aquifex aeolicus VF5

to see the rest 2 gene click here
GO terms
  • BP: GO:0055114 : oxidation reduction : IEA
  • MF: GO:0046872 : metal ion binding : IEA
  • MF: GO:0051745 : 4-hydroxy-3-methylbut-2-en-1-yl diphosphate reductase activity : IEA
  • BP: GO:0016114 : terpenoid biosynthetic process : IEA
  • MF: GO:0051536 : iron-sulfur cluster binding : IEA
  • BP: GO:0019288 : isopentenyl diphosphate biosynthetic process, mevalonate-independent pathway : IEA
  • BP: GO:0008299 : isoprenoid biosynthetic process : IEA
  • MF: GO:0016491 : oxidoreductase activity : IEA
  • MF: GO:0051538 : 3 iron, 4 sulfur cluster binding : IEA
Domain Structure from CDD
  • ispH_lytB: (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate reductase (IPP and DMAPP forming). Escherichia coli LytB protein had bee.... (More)
  • LYTB: LytB protein. 4-hydroxy-3-methylbut-2-enyl diphosphate reductase; Provisional

See domain structure on NCBI Conserved Domain Database
Domain structure from Pfam
See domain structure on Pfam Database
The table at right lists genes that may be "functionally linked to" (i.e., participate in a common biological process, or form a protein complex with) the subject gene of this page, as determined by two sequence-independent methods, including phylogenetic profiling and operon membership (determined by OperonDB). (Info.) These linkages may also be viewed graphically using the program VisANT, by clicking on the headers of the table. Note: VisANT requires Java. To install the latest version of Java, see
phylogenetic profile
HP0398hypothetical protein
rpsA30S ribosomal protein S1
pheTphenylalanyl-tRNA synthetase subunit beta
HP04013-phosphoshikimate 1-carboxyvinyltransferase
HP03541-deoxy-D-xylulose-5-phosphate synthase 
ispG4-hydroxy-3-methylbut-2-en-1-yl diphosphate syntha 
HP02161-deoxy-D-xylulose 5-phosphate reductoisomerase 
ispDFbifunctional 2-C-methyl-D-erythritol 4-phosphate c 
HP0772N-acetylmuramoyl-L-alanine amidase (amiA) 
HP14434-diphosphocytidyl-2-C-methyl-D-erythritol kinase 
HP0823hypothetical protein 
Metabolic Annotation from Palsson Lab

Metabolic Reaction: DMPPS

1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (dmpp)
h2mb4p[c] + h[c] + nadh[c] -> dmpp[c] + h2o[c] + nad[c]
Isoprenoid Biosynthesis

Metabolic Reaction: IPDPS

1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (ipdp)
h2mb4p[c] + h[c] + nadh[c] -> h2o[c] + ipdp[c] + nad[c]
Isoprenoid Biosynthesis

Source: Ported to COMBREX by Segre's Lab