Physicochemical, Catalytic, and Immunochemical Properties of Fumarases Crystallized Separately from Mitochondrial and Cytosolic Fractions of Rat Liver1

Kobayashi, Kazuo; Yamanishi, Tomoko; Tuboi, Syozo

doi:10.1093/oxfordjournals.jbchem.a133394

Cited by 29 publications

(16 citation statements)

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“…FumC is a class II enzyme which does not require iron for its activity, and it forms thermostable tetramers containing identical subunits of M r 50,000 (34). The fumC gene does not show any homology to either the fumA or fumB genes, but it exhibits extensive homology to the fumarase sequences of Bacillus subtilis, Saccharomyces cerevisiae, and mammals (13,14,18,24,26,35). It also shows similarity with the aspartate gene, aspA, of E.…”

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confidence: 99%

Oxygen- and Growth Rate-Dependent Regulation of Escherichia coli Fumarase (FumA, FumB, and FumC) Activity

Tseng

Lin

et al. 2001

J Bacteriol

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Escherichia coli contains three biochemically distinct fumarases which catalyze the interconversion of fumarate to L-malate in the tricarboxylic acid cycle. Batch culture studies indicated that fumarase activities varied according to carbon substrate and cell doubling time. Growth rate control of fumarase activities in the wild type and mutants was demonstrated in continuous culture; FumA and FumC activities were induced fourto fivefold when the cell growth rate (k) was lowered from 1.2/h to 0.24/h at 1 and 21% O 2 , respectively. There was a twofold induction of FumA and FumC activities when acetate was utilized instead of glucose as the sole carbon source. However, these fumarase activities were still shown to be under growth rate control. Thus, the activity of the fumarases is regulated by the cell growth rate and carbon source utilization independently. Further examination of FumA and FumC activities in a cya mutant suggested that growth rate control of FumA and FumC activities is cyclic AMP dependent. Although the total fumarase activity increased under aerobic conditions, the individual fumarase activities varied under different oxygen levels. While FumB activity was maximal during anaerobic growth (k ‫؍‬ 0.6/h), FumA was the major enzyme under anaerobic cell growth, and the maximum activity was achieved when oxygen was elevated to 1 to 2%. Further increase in the oxygen level caused inactivation of FumA and FumB activities by the high oxidized state, but FumC activity increased simultaneously when the oxygen level was higher than 4%. The same regulation of the activities of fumarases in response to different oxygen levels was also found in mutants. Therefore, synthesis of the three fumarase enzymes is controlled in a hierarchical fashion depending on the environmental oxygen that the cell encounters.

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confidence: 99%

Oxygen- and Growth Rate-Dependent Regulation of Escherichia coli Fumarase (FumA, FumB, and FumC) Activity

Tseng

Lin

et al. 2001

J Bacteriol

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“…FumA activity can be restored by anaerobic incubation with iron and thiol. The fumC gene does not show any homology with either the fumA or fumB gene, but it exhibits extensive homology with the fumarase genes of Bacillus subtilis, Saccharomyces cerevisiae, and mammals (19,20,26,32,37,45). It also has similarity to the aspartase gene, aspA, of E. coli (38,42).…”

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Oxygen, iron, carbon, and superoxide control of the fumarase fumA and fumC genes of Escherichia coli: role of the arcA, fnr, and soxR gene products

1995

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The tricarboxylic acid cycle enzyme fumarase catalyzes the interconversion of fumarate to L-malate. Escherichia coli contains three biochemically distinct fumarases. While the fumA and fumB genes encode heat-labile, iron-containing fumarases, the fumC gene product is a heat-stable fumarase which does not require iron for activity. To study how the fumA and fumC genes are regulated, we constructed lacZ operon fusions to the fumA and/or fumC upstream regions. Expression of the fumA and fumC genes was lowest during anaerobic cell growth, in support of the proposed roles of FumA and FumC as aerobic fumarases. Transcription of the fumC gene was shown to be complex: it was dependent on both the fumA and fumC promoters. Anaerobic expression from the fumA promoter was derepressed in both an arcA and a fnr mutant, while expression from the fumC promoter was derepressed in only the arcA strain. The fumA promoter was also shown to be catabolite controlled, whereas the fumC promoter was relatively unaffected by the type of carbon used for cell growth. Cellular iron limitation stimulated fumC but not fumA expression. Superoxide radicals also caused increased fumC gene expression; fumA expression was unaffected. Both the superoxide control and the iron control of fumC expression required the SoxR regulatory protein. These studies suggest different physiological roles for the FumA and FumC fumarases. The iron-containing FumA fumarase is the more abundant enzyme under most conditions of aerobic cell growth except when iron is limiting; FumC, which lacks iron, appears to be a backup enzyme that is synthesized optimally only when iron is low or when superoxide radicals accumulate.

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“…Addition of 10 mM-K3PO4 to the test mixture resulted in an increase of K , for malate and fumarate to 0-45 mM and 0.27 mM respectively. The inhibition of S. solfataricus fumarase by phosphate was less than that for rat liver fumarase, for which the addition of 10 mM-K3PO4 resulted in an increase of K , from 0.013 mM to 0.33 mM for fumarate and 0.14 mM to 0.60 mM for malate (Kobayashi et al, 1981).…”

Section: Substrate Spec8cities and Kinetic Studiesmentioning

confidence: 75%

“…Since it was reported that the kinetic constants of rat liver fumarase were affected by phosphate (Kobayashi et al, 1981), the effect of potassium phosphate on kinetic properties of the S. solfataricus enzyme was tested. Addition of 10 mM-K3PO4 to the test mixture resulted in an increase of K , for malate and fumarate to 0-45 mM and 0.27 mM respectively.…”

Section: Substrate Spec8cities and Kinetic Studiesmentioning

confidence: 99%

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Purification and properties of a thermostable fumarate hydratase from the archaeobacterium Sulfolobus solfataricus

Puchegger

Redl²,

Stöffler³

1990

Journal of General Microbiology

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~~Fumarate hydratase (EC 4.2.1.2) from the extremely thermophilic archaeobacterium Solfofobus solfatmais has been purified to homogeneity by a rapid purification procedure using chromatography and highperformance size-exclusion chromatography, and the enzyme's physical and biochemical properties have been determined. The native enzyme has a molecular mass of 170 kDa and is composed of identical subunits with a molecular mass of 45 kDa, thus indicating a tetrameric structure similar to fumarases isolated from other organisms. The enzyme was active at temperatures ranging from 40 "C to 90 "C, with a maximum activity at 85 OC.The pH optimum for generation of fumarate was found to be pH8.0. The enzyme showed high stability to denaturation by heat and organic solvents.

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Physicochemical, Catalytic, and Immunochemical Properties of Fumarases Crystallized Separately from Mitochondrial and Cytosolic Fractions of Rat Liver1

Cited by 29 publications

References 0 publications

Oxygen- and Growth Rate-Dependent Regulation of Escherichia coli Fumarase (FumA, FumB, and FumC) Activity

Oxygen- and Growth Rate-Dependent Regulation of Escherichia coli Fumarase (FumA, FumB, and FumC) Activity

Oxygen, iron, carbon, and superoxide control of the fumarase fumA and fumC genes of Escherichia coli: role of the arcA, fnr, and soxR gene products

Purification and properties of a thermostable fumarate hydratase from the archaeobacterium Sulfolobus solfataricus

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