• BMB Reports
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• v.30 no.4
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• pp.246-252
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• 1997

Malonate decarboxylase from Acinetobacter calcoaceticus is shown to have malonyl-CoA: acetate CoA transferase. acetyl-CoA: malonate CoA transferase, and malonyl-CoA decarboxylase activity. These enzyme activities were elucidated by isotope exchange reactions. The enzyme modified by N-ethylmaleimide completely lost its malonate decarboxylase activity, whereas it still kept CoA transferases and malonyl-CoA decarboxylase activities. The existence of CoA transferases and malonyl-CoA decarboxylase activity is clear, but their physiological significance is obscure. The catalytic reactions for two eoA transfers and malonyl-CoA decarboxylation proceed via a cyclic mechanism, which is through two covalent intermediates, enzyme-Smalonyl and enzyme-S-acetyL proposed for malonate decarboxylation of the enzyme.

• BMB Reports
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• v.28 no.2
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• pp.107-111
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• 1995

In malonate grown Pseudomonas fluorescens, malonate decarboxylase and acetyl-CoA synthetase were induced, whereas in Acinetobacter calcoaceticus malonate decarboxylase, acetate kinase, and phosphate acetyltransferase were induced. In both bacteria malonate decarboxylase was the first, key enzyme catalyzing the decarboxylation of malonate to acetate, and it was localized in the periplasmic space. Acetate thus formed was metabolized to acetyl-CoA directly by acetyl-CoA synthetase in Pseudomonas, and to acetyl-CoA via acetyl phosphate by acetate kinase and phosphate acetyltransferase in Acinetobacter.

• BMB Reports
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• v.32 no.4
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• pp.414-418
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• 1999

A novel gene for malonyl-CoA decarboxylase was discovered in the mat operon, which encodes a set of genes involved in the malonate metabolism of Rhizobium trifolii (An and Kim, 1998). The subunit mass determined by SDS-PAGE was 53 kDa, which correspond to the deduced mass from the sequence data. The molecular mass of the native enzyme determined by field flow fractionation was 208 kDa, indicating that R. trifolii malonyl-CoA decarboxylase is homotetrameric. R. trifolii malonyl-CoA decarboxylase converted malonyl-CoA to acetyl-CoA with a specific activity of 100 unit/mg protein. Methylmalonyl-CoA was decarboxylated with a specific activity of 0.1 unit/mg protein. p-Chloromercuribenzoate inhibited this enzyme activity, suggesting that thiol group(s) is(are) essential for this enzyme catalysis. Database analysis showed that malonyl-CoA decarboxylase from R. trifolii shared 32.7% and 28.1% identity in amino acid sequence with those from goose and human, respectively, and it would be located in the cytoplasm. However, there is no sequence homology between this enzyme and that from Saccharopolyspora erythreus, suggesting that malonyl-CoA decarboxylases from human, goose, and R. trifolii are in the same class, whereas that from S. erythreus is in a different class or even a different enzyme, methylmalonyl-CoA decarboxylase. According to the homology analysis, Cys-214 among three cysteine residues in the enzyme was found in the homologous region, suggesting that the cysteine was located at or near the active site and plays a critical role in catalysis.

• BMB Reports
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• v.35 no.2
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• pp.213-219
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• 2002

Malonyl-CoA decarboxylase (E.C.4.1.1.9) catalyzes the conversion of malonyl-CoA to acetyl-CoA. Although the metabolic role of this enzyme has not been fully defined, it has been reported that its deficiency is associated with mild mental retardation, seizures, hypotonia, cadiomyopathy, developmental delay, vomiting, hypoglycemia, metabolic acidosis, and malonic aciduria. Here, we isolated a cDNA clone for malonyl CoA decarboxylase from a rat brain cDNA library, expressed it in E. coli, and characterized its biochemical properties. The full-length cDNA contained a single open-reading frame that encoded 491 amino acid residues with a calculated molecular weight of 54, 762 Da. Its deduced amino acid sequence revealed a 65.6% identity to that from the goose uropigial gland. The sequence of the first 38 amino acids represents a putative mitochondrial targeting sequence, and the last 3 amino acid sequences (SKL) represent peroxisomal targeting ones. The expression of malonyl CoA decarboxylase was observed over a wide range of tissues as a single transcript of 2.0 kb in size. The recombinant protein that was expressed in E. coli was used to characterize the biochemical properties, which showed a typical Michaelis-Menten substrate saturation pattern. The $K_m$ and $V_{max}$ were calculated to be $68\;{\mu}M$ and $42.6\;{\mu}mol/min/mg$, respectively.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.97-98
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• 2003

Current study was aimed to understand an interaction between Dopa decarboxylase (DDC) and proteins that specifically binds to DDC in the silkworm, Bombyx mori. Materials and Methods: Materials-Animal: Bombyx mori Construction of GST fusion protein Preparation of lysates: Protein extracted from whole body of Bombyx mori Methods-In vitro binding assay with lysates, Peptide sequence and RACE-PCR (omitted)

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.49-49
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• 2003

DOPA decarboxylase (DDC), which converts DOPA to dopamine, is important for many biological event such as cuticular melanization, sclerotization and neurotransmission in insects. Recently, it has been also shown that DDC activity is correlated with pupal diapause in M. brassicae. The silkworm, Bombyx mori is a typical insect diapausing at early embryonic stage. (omitted)

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2001.04a
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• pp.53-53
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• 2001

No Abstract. See Full-text

• Korean Journal of Microbiology
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• v.32 no.3
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• pp.192-197
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• 1994

Pseudomonas fluorescens which is able to utilize malonate as a sole carbon source was found to contain a novel 60 kb plasmid, which encodes the genes for the proteins to assimilate malonate, including malonate decarboxylase and acetyl-CoA synthetase. The evidence is as follows: The Pseudomonas cured with mitomycin C was unable to grow on malonate-medium as well as it lost plasmid. The plasmid isolated from the Pseudomonas could be introduced into E. coli strain JM103 and DH1 by transformation. The transformed E. coli was able to grow on malonate-medium and could transmit its plasmid back to the cured P. fluorescens by conjugation. The existence of the plasmid in the transformed E. coli was confirmed by hybridization with a labeled probe prepared from 12 kb segment of the plasmid. Dot hybridization showed that the copy number of the plasmid in the transformed E. coli is at least 13 times higher than in the wild type P. fluorescens. The two key enzymes, malonate decarboxylase and acetyl-CoA synthetase, were inducible by malonate in the transformed E. coli.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.151-152
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• 2003

To understand the relationship between DDC activity and diapause or other biological events in Antheraea yamamai, we have determined a complete cDNA sequence of DDC homologue from Antheraea yamamai and have examined expression patterns in various tissues by Northern blot analysis. (omitted)

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2001.11a
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• pp.128-128
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• 2001