• BMB Reports
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• 제28권2호
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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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• 제30권4호
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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.

• 미생물학회지
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• 제32권3호
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• pp.192-197
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• 1994

말론산을 탄소원으로 하여 성장하는 Pseudomonas fluorescens에서 60 kb 정도의 plasmid를 발견하였다. 이 plasmid를 curing한 Pseudomonas는 malonate 배지에서 자라지 못하였고 plasmid도 소실되었다. 또한 이 plasmid를 transformation과 conjugation으로 각각 E. coli와 cured P. fluorescens로 이동시킨 결과 이 plasmid를 받은 transformed E. coli와 conjugant P. fluorescens는 malonate를 탄소원으로 하여 성장하였고 malonate 대사에 관련된 효소인 malonate decarboxylase와 acetyl-CoA synthetase의 활성이 측정되었다. Western blotting을 통하여 tansformed E. coli에서 P. fluorescens와 동일한 acetyl-CoA synthetase가 malonate에 의해 induction됨을 확인하였다.

• BMB Reports
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• 제35권5호
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• pp.443-451
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• 2002

Malonate is a three-carbon dicarboxylic acid. It is well known as a competitive inhibitor of succinate dehydrogenase. It occurs naturally in biological systems, such as legumes and developing rat brains, which indicates that it may play an important role in symbiotic nitrogen metabolism and brain development. Recently, enzymes that are related to malonate metabolism were discovered and characterized. The genes that encode the enzymes were isolated, and the regulation of their expression was also studied. The mutant bacteria, in which the malonate-metabolizing gene was deleted, lost its primary function, symbiosis, between Rhizobium leguminosarium bv trifolii and clover. This suggests that malonate metabolism is essential in symbiotic nitrogen metabolism, at least in clover nodules. In addition to these, the genes matB and matC have been successfully used for generation of the industrial strain of Streptomyces for the production of antibiotics.

• BMB Reports
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• 제30권2호
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• pp.132-137
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• 1997

In order to compare molecular structure, malonate decarboxylases from Acinetobacter calcoaceticus, Pseudomonas fluorescens, and Pseudomonas putida aerobically grown on malonate, were purified by the method employing streptomycin sulfate treatment, chromatography with PBE 94 and ${\omega}-aminohexyl$ agarose. Molecular masses were estimated to be 185, 200, and 200 kDa, respectively. All malonate decarboxylases were multimeric enzymes consisting of four different subunits, $2{\alpha},\;1{\beta},\;1{\gamma},\;and\;1{\delta}$. The molecular masses of the Pseudomonas enzyme subunits were $65({\alpha})$, $33({\beta})$, $30({\gamma})$, and $11kDa({\delta})$; which are very similar to those, $65({\alpha})$, $32({\beta})$, $25({\gamma})$, and $11kDa({\delta})$ of Acinetobacter enzyme. The ${\delta}-subunit$ of the active form of the enzymes was acetylated. The acetyl group may form a thioester bond with the thiol group of the prosthetic group covalently linked to the enzyme. It suggests that such molecular organization is common in all malonate decarboxylases.

• BMB Reports
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• 제32권4호
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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.

• 대한미생물학회지
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• 제22권4호
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• pp.427-433
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• 1987

One hundred and thirty-six strains of Klebsiella pneumoniae were isolated from clinical specimen taken from pediatric patiants at 6 different hospitals and identified, characterized and investigated on the patterns of antibiotic resistance. The 136 strains showed the positive reactions in the 17 tests; Voges-Proskauer, ONPG, cirate utilization, KCN degradation, productions of lysine decarboxylase, acid and gas from glucose, utilizations of malonate, manitol, rhamnose, salicin, sucrose, raffinose, arabinose, lactose, sucrose, inositol and raffinose, but the strains showed the negative reactions in the 8 tests; production of $H_2S$, indole, arginine dehydrolase, ornithine decaraoxylase, phenylalanine deaminase, motility, methly red and gelatin liquefaction. 41 did not utilize dulcitol, and 32 did not utilize adonitol. The 36 out of them produced klebecin. The 136 strains were resistant to ampicillin, 2 to gentamicin, 14 to cephalothin, 16 to chloramphenicol, 8 to kanamycin, 13 to streptomycin, and 17 to tetracycline. Twenty strains were resistant to 2 kinds of antibiotics 5 strains to 3, 4 to 4 and 1 to 6 and 7.