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- Name help_outline geranylgeranyl diphosphate Identifier CHEBI:57533 Charge -3 Formula C20H33O7P2 InChIKeyhelp_outline OINNEUNVOZHBOX-UHFFFAOYSA-K SMILEShelp_outline CC(C)=CCCC(C)=CCCC(C)=CCCC(C)=CCOP([O-])(=O)OP([O-])([O-])=O 2D coordinates Mol file for the small molecule Search links Involved in 66 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline tuberculosinyl diphosphate Identifier CHEBI:58822 Charge -3 Formula C20H33O7P2 InChIKeyhelp_outline BPSHPRCHMGHBGC-AHKHSGQUSA-K SMILEShelp_outline C[C@H]1CC=C2[C@@H](CCCC2(C)C)[C@]1(C)CC\C(C)=C\COP([O-])(=O)OP([O-])([O-])=O 2D coordinates Mol file for the small molecule Search links Involved in 5 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Cross-references
| RHEA:25621 | RHEA:25622 | RHEA:25623 | RHEA:25624 | |
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| Reaction direction help_outline | undefined | left-to-right | right-to-left | bidirectional |
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Publications
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Characterization of the Rv3377c gene product, a type-B diterpene cyclase, from the Mycobacterium tuberculosis H37 genome.
Nakano C., Hoshino T.
The Rv3377c gene from the Mycobacterium tuberculosis H37 genome is specifically limited to those Mycobacterium species that cause tuberculosis. We have demonstrated that the gene product of Rv3377c is a diterpene cyclase that catalyzes the formation of tuberculosinol from geranylgeranyl diphosphat ... >> More
The Rv3377c gene from the Mycobacterium tuberculosis H37 genome is specifically limited to those Mycobacterium species that cause tuberculosis. We have demonstrated that the gene product of Rv3377c is a diterpene cyclase that catalyzes the formation of tuberculosinol from geranylgeranyl diphosphate (GGPP). However, the characteristics of this enzyme had not previously been studied in detail with homogeneously purified enzyme. The purified enzyme catalyzed the synthesis of tuberculosinyl diphosphate from GGPP, but it did not bring about the synthesis of tuberculosinol. Optimal conditions for the highest activity were found to be as follows: pH 7.5, 30 degrees C, Mg(II) (0.1 mM), and Triton X-100 (0.1 %). Under these conditions, the kinetic values of K(M) and k(cat) were determined to be 11.7+/-1.9 microM for GGPP and 12.7+/-0.7 min(-1), respectively, whereas the specific activity was 186 nmol min(-1) mg(-1). The enzyme activity was inhibited at substrate concentrations higher than 50 microM. The catalytic activity was strongly inhibited by 15-aza-dihydrogeranylgeraniol and 5-isopropyl-N,N,N,2-tetramethyl-4-(piperidine-1-carbonyloxy)benzenaminium chloride (Amo-1618). The DXDTT(293-297) motif, corresponding to the DXDDTA motif conserved among terpene cyclases, was mutated in order to investigate its function. The middle D295 was found to be the most crucial entity for the catalysis. D293 and two threonine residues function synergistically to enhance the acidity of D295, possibly through hydrogen-bonding networks. The Rv3377c enzyme could also react with (14R/S)-14,15-oxidoGGPP to generate 3alpha- and 3beta-hydroxytuberculosinyl diphosphate. Conformational analyses were carried out with deuterium-labeled GGPP and oxidoGGPP. We found that GGPP and (14R)-oxidoGGPP adopted a chair/chair conformation, but (14S)-oxidoGGPP adopted a boat/chair conformation. Interestingly, the conformations of oxidoGGPP for the A-ring formation are the opposite of those of oxidosqualene when it is used as a substrate by squalene cyclases for the biosynthesis of hopene and tetrahymanol. (3R)-Oxidosqualene is folded in a boat conformation, whereas (3S)-2,3-oxidosqualene folds into a chair conformation, for the formation of the A-rings of the hopene and tetrahymanol skeletons, respectively. << Less
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Mycobacterium tuberculosis H37Rv3377c encodes the diterpene cyclase for producing the halimane skeleton.
Nakano C., Okamura T., Sato T., Dairi T., Hoshino T.
The cloning and functional expression of Mycobacterium tuberculosis Rv3377c in Escherichia coli revealed that this gene encodes the diterpene cyclase for producing (+)-5(6),13-halimadiene-15-ol, which accepts geranylgeranyldiphosphate as the intrinsic substrate.
Chem. Commun. (Camb.) 8:1016-1018(2005) [PubMed] [EuropePMC]