Skipping of exon 2 and exons 2 plus 3 of HMG-CoA lyase (HL) gene produces the loss of beta sheets 1 and 2 in the recently proposed (beta-alpha)8 TIM Barrel model of HL

Puisac, Beatriz; López-Viñas, Eduardo; Moreno, Susana Elisa; Mir, Cecilia; Pérez‐Cerdá, Celia; Menao, Sebastián; Lluch, Dolores; Pié, Ángeles; Gómez‐Puertas, Paulino; Casals, Núria; Ugarte, Magdalena; Hegardt, Fausto G.; Pié, Juan

doi:10.1016/j.bpc.2004.12.031

Cited by 11 publications

(10 citation statements)

References 26 publications

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“…These results confirm the Mediterranean mutation as the second most frequent mutation in the world (31 cases), with a specific location in the Iberian Peninsula, where it was carried by 100% of the Portuguese patients (13 cases) (Carrasco, et al, 2007; and by 61% of Spanish (11 cases) (Casale, et al, 1998;Puisac, et al, 2005). This mutation was also found in an Argentinian patient of Spanish ancestry and in one Moroccoan; and since the other studied Moroccoan patient carries it , the Mediterranean mutation may have a high incidence in that country.…”

Section: Mutational Updatesupporting

confidence: 77%

Ten novelHMGCLmutations in 24 patients of different origin with 3-hydroxy-3-methyl-glutaric aciduria

et al. 2009

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3-Hydroxy-3-methylglutaric aciduria is a rare autosomal recessive genetic disorder that affects ketogenesis and L-leucine catabolism. The clinical acute symptoms include vomiting, convulsions, metabolic acidosis, hypoketotic hypoglycaemia and lethargy. To date, 33 mutations in 100 patients have been reported in the HMGCL gene. In this study 10 new mutations in 24 patients are described. They include: 5 missense mutations: c.109G>A, c.425C>T, c.521G>A, c.575T>C and c.598A>T, 2 nonsense mutations: c.242G>A and c.559G>T, one small deletion: c.853delC, and 2 mutations in intron regions: c.497+4A>G and c.750+1G>A. Two prevalent mutations were detected, 109G>T (E37X) in 38% of disease alleles analyzed and c.504_505delCT in 10% of them. Although patients are mainly of European origin (71%) and mostly Spanish (54%), the group is ethnically diverse and includes, for the first time, patients from Pakistan, Palestine and Ecuador. We also present a simple, efficient method to express the enzyme and we analyze the possible functional effects of missense mutations. The finding that all identified missense mutations cause a >95% decrease in the enzyme activity, indicates that the disease appears only in very severe genotypes."

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Section: Mutational Updatesupporting

confidence: 77%

Ten novelHMGCLmutations in 24 patients of different origin with 3-hydroxy-3-methyl-glutaric aciduria

et al. 2009

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“…A homology model for the Michaelis complex of the enzyme has been published based on the structure of HisA (PDB code 1QO2) (14,15). In this model, the lipophilic moiety of the CoA passes through the core of the TIM barrel (i.e.…”

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confidence: 99%

Crystal Structures of Two Bacterial 3-Hydroxy-3-methylglutaryl-CoA Lyases Suggest a Common Catalytic Mechanism among a Family of TIM Barrel Metalloenzymes Cleaving Carbon-Carbon Bonds

Forouhar

Hussain

Farid

et al. 2006

Journal of Biological Chemistry

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The enzyme 3-hydroxy-3-methylglutaryl-coenzyme A (HMGCoA) lyase catalyzes the terminal steps in ketone body generation and leucine degradation. Mutations in this enzyme cause a human autosomal recessive disorder called primary metabolic aciduria, which typically kills victims because of an inability to tolerate hypoglycemia. Here we present crystal structures of the HMG-CoA lyases from Bacillus subtilis and Brucella melitensis at 2.7 and 2.3 Å resolution, respectively. These enzymes share greater than 45% sequence identity with the human orthologue. Although the enzyme has the anticipated triose-phosphate isomerase (TIM) barrel fold, the catalytic center contains a divalent cation-binding site formed by a cluster of invariant residues that cap the core of the barrel, contrary to the predictions of homology models. Surprisingly, the residues forming this cation-binding site and most of their interaction partners are shared with three other TIM barrel enzymes that catalyze diverse carbon-carbon bond cleavage reactions believed to proceed through enolate intermediates (4-hydroxy-2-ketovalerate aldolase, 2-isopropylmalate synthase, and transcarboxylase 5S). We propose the name "DRE-TIM metallolyases" for this newly identified enzyme family likely to employ a common catalytic reaction mechanism involving an invariant AspArg-Glu (DRE) triplet. The Asp ligates the divalent cation, while the Arg probably stabilizes charge accumulation in the enolate intermediate, and the Glu maintains the precise structural alignment of the Asp and Arg. We propose a detailed model for the catalytic reaction mechanism of HMG-CoA lyase based on the examination of previously reported product complexes of other DRE-TIM metallolyases and induced fit substrate docking studies conducted using the crystal structure of human HMG-CoA lyase (reported in the accompanying paper by Fu, et al.

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“…No significant variations of overall protein were detected when compared with the first model proposed. The root-mean-square deviation (RMSD) value between the corresponding backbone atoms was 1.3Å, which indicates satisfactory superimposition and reinforces both 3D models (Puisac et al 2005).…”

Section: Introductionmentioning

confidence: 76%

“…In Italy, only four patients have been described at the molecular level (Mitchell et al 1995;Casals et al 1997;Funghini et al 2001;present study) and each patient carries a different mutation, indicating that there is no predominant mutation in this country, in contrast to other Mediterranean countries (Spain and Portugal) where mutation E37X predominates Casale et al 1998;Puisac et al 2005;Cardoso et al 2004). DNA fragments amplified with primers Mut203F and HLE7R were digested by XhoI.…”

Section: Resultsmentioning

confidence: 99%

A single‐residue mutation, G203E, causes 3‐hydroxy‐3‐methylglutaric aciduria by occluding the substrate channel in the 3D structural model of HMG‐CoA lyase

Mir

López-Viñas

Aledo

et al. 2006

J of Inher Metab Disea

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3-Hydroxy-3-methylglutaric aciduria is a rare autosomal recessive genetic disorder that affects ketogenesis and leucine metabolism. The disease is caused by mutations in the gene coding for 3-hydroxy-3-methylglutaryl-coenzyme A lyase (HL). To date 26 different mutations have been described. A (betaalpha)(8) TIM barrel structure has been proposed for the protein, and almost all missense mutations identified so far localize in the beta sheets that define the inside cavity. We report an Italian patient who bears homozygously a novel HL mutation, c.608G > A (p. G203E) in beta sheet six. A structural model of the mutated protein suggests that glutamic acid 203 impedes catalysis by blocking the entrance to the inner cavity of the enzyme. Loss of functionality has been confirmed in expression studies in E. coli, which demonstrate that the G203E mutation completely abolishes enzyme activity. Beta sheet six and beta sheet two are the two protein regions that accumulate most missense mutations, indicating their importance in enzyme functionality. A model for the mechanism of enzyme function is proposed.

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Skipping of exon 2 and exons 2 plus 3 of HMG-CoA lyase (HL) gene produces the loss of beta sheets 1 and 2 in the recently proposed (beta-alpha)8 TIM Barrel model of HL

Cited by 11 publications

References 26 publications

Ten novelHMGCLmutations in 24 patients of different origin with 3-hydroxy-3-methyl-glutaric aciduria

Ten novelHMGCLmutations in 24 patients of different origin with 3-hydroxy-3-methyl-glutaric aciduria

Crystal Structures of Two Bacterial 3-Hydroxy-3-methylglutaryl-CoA Lyases Suggest a Common Catalytic Mechanism among a Family of TIM Barrel Metalloenzymes Cleaving Carbon-Carbon Bonds

A single‐residue mutation, G203E, causes 3‐hydroxy‐3‐methylglutaric aciduria by occluding the substrate channel in the 3D structural model of HMG‐CoA lyase

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