IspG‐Catalyzed Positional Isotopic Exchange in Methylerythritol Cyclodiphosphate of the Deoxyxylulose Phosphate Pathway: Mechanistic Implications

Xiao, Youli; Rooker, Debra R.; You, Quincy; Meyers, Caren L. Freel; Liu, Pinghua

doi:10.1002/cbic.201000716

Cited by 20 publications

(27 citation statements)

References 29 publications

(33 reference statements)

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“…It is known that MEcPP itself is stable for weeks at room temperature and such a positional isotope exchange depends absolutely on the presence of holo-IspG. Since the positional isotope exchange experiment was conducted in the absence of reductants, this result not only provides evidence supporting the reversible C-O bond cleavage at the MEcPP ( 16 ) C 2 position, but also implies that the formation of a cation intermediate occurs prior to any redox-chemistry (69). How IspG facilitates the MEcPP ( 16 ) C 2 C-O bond cleavage remains to be addressed.…”

Section: Mechanistic Studies Of the Mep Pathway Enzymesmentioning

confidence: 88%

“…(55, 68). In the cation model, reduction of the cation intermediate ( 29 ) (69) leads to a radical intermediate ( 30 ), which undergoes dehydration to 31 through a C-O bond cleavage mechanism as in the case of radical mediated dehydration reactions (70). Coordination of the C 3 -OH group of MEcPP ( 16 ) to the [4Fe-4S] cluster may also facilitate the 30 → 31 transformation as in the case of aconitase (71).…”

Section: Mechanistic Studies Of the Mep Pathway Enzymesmentioning

confidence: 99%

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Methylerythritol Phosphate Pathway of Isoprenoid Biosynthesis

Zhao

Chang

Xiao

et al. 2013

Annu. Rev. Biochem.

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266

174

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Isoprenoids are a class of natural products with more than 50,000 members. All isoprenoids are constructed from two precursors, isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP). Two of the most important discoveries in isoprenoid biosynthetic studies in recent years are the elucidation of a second isoprenoid biosynthetic pathway (the methylerythritol phosphate (MEP) pathway) and a modified mevalonate (MVA) pathway. In this review, mechanistic insights on the MEP pathway enzymes are summarized. Since many isoprenoids have important biological activities, the need to produce them in sufficient quantities for downstream research efforts or commercial application is apparent. Recent advances in both the MVA and MEP pathway-based synthetic biology efforts are also illustrated by reviewing the landmark work of artemisinic acid and taxadien-5α-ol production through microbial fermentations.

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Section: Mechanistic Studies Of the Mep Pathway Enzymesmentioning

confidence: 88%

Section: Mechanistic Studies Of the Mep Pathway Enzymesmentioning

confidence: 99%

Methylerythritol Phosphate Pathway of Isoprenoid Biosynthesis

Zhao

Chang

Xiao

et al. 2013

Annu. Rev. Biochem.

Self Cite

266

174

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“…Despite the availability of holo and substrate-bound crystal structures [6-8] as well as extensive spectroscopic data from electron paramagnetic resonance (EPR), and isotope labelling experiments [4, 14], the identity and lifetime of the IspG reaction intermediates has been controversial.…”

Section: Introductionmentioning

confidence: 99%

Atomic-Resolution Structures of Discrete Stages on the Reaction Coordinate of the [Fe 4 S 4 ] Enzyme IspG (GcpE)

Quitterer

Frank

Wang

et al. 2015

Journal of Molecular Biology

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IspG is the penultimate enzyme in non-mevalonate biosynthesis of the universal terpene building blocks isopentenyl diphosphate and dimethylallyl diphosphate. Its mechanism of action has been the subject of numerous studies but remained unresolved due to difficulties in identifying distinct reaction intermediates. Using a moderate reducing agent as well as an epoxide substrate analogue, we were now able to trap and crystallographically characterize various stages in the IspG catalyzed conversion of 2-C-methyl-D-erythritol-2,4-cyclo-diphosphate (MEcPP) to (E)-1-hydroxy-2-methylbut-2-enyl-4-diphosphate (HMBPP). In addition, the enzyme's structure was determined in complex with several inhibitors. These results, combined with recent electron paramagnetic resonance data, allowed us to deduce a detailed and complete IspG catalytic mechanism which describes all stages from initial ring opening to formation of HMBPP via discrete radical and carbanion intermediates. The data presented in this article provide a guide for the design of selective drugs against many pro- and eukaryotic pathogens to which the non-mevalonate pathway is essential for survival and virulence.

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“…instead suggested that IspG-catalysis might involve a carbocation intermediate ( 31 , Figure 3B) [43,44]. The observation of a positional isotope exchange for the MEcPP C 2 bridging oxygen provided evidence for a reversible cleavage at this position, which is consistent with the formation of a carbocation intermediate 31 [45]. Based on the characterization of paramagnetic species detected during IspG steady-state turnover, Oldfield and co-workers went on to suggest that IspG catalysis might also involve an organometallic intermediate (e.g., 34 ) downstream of the carbocation intermediate 31 [46].…”

Section: Mechanictic Studies On Ispg and Isphmentioning

confidence: 88%

Current development in isoprenoid precursor biosynthesis and regulation

Chang

Song

Liu

et al. 2013

Current Opinion in Chemical Biology

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111

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Isoprenoids are one of the largest classes of natural products and all of them are constructed from two precursors, isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP). For decades, the mevalonic acid (MVA) pathway was proposed to be the only IPP and DMAPP biosynthetic pathway. This review summarizes the newly discovered IPP and DMAPP production pathways since late 1990s, their distribution among different kingdoms, and their roles in secondary metabolite production. These new IPP and DMAPP production pathways include the methylerythritol phosphate (MEP) pathway, a modified MVA pathway, and the 5-Methylthioadenosine shunt pathway. Relative to the studies on the MVA pathway, information on the MEP pathway regulation is limited and the mechanistic details of several of its novel transformations remain to be addressed. Current status on both MEP pathway regulation and mechanistic issues are also presented.

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IspG‐Catalyzed Positional Isotopic Exchange in Methylerythritol Cyclodiphosphate of the Deoxyxylulose Phosphate Pathway: Mechanistic Implications

Cited by 20 publications

References 29 publications

Methylerythritol Phosphate Pathway of Isoprenoid Biosynthesis

Methylerythritol Phosphate Pathway of Isoprenoid Biosynthesis

Atomic-Resolution Structures of Discrete Stages on the Reaction Coordinate of the [Fe 4 S 4 ] Enzyme IspG (GcpE)

Current development in isoprenoid precursor biosynthesis and regulation

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