CO2 control of fruiting in Schizophyllum commune: noninvolvement of sustained isocitrate lyase derepression

1970 ◽  
Vol 16 (7) ◽  
pp. 605-608 ◽  
Author(s):  
D. A. Cotter ◽  
A. J. LaClave ◽  
W. S. Wegener ◽  
D. J. Niederpruem
Keyword(s):  
Carbon Dioxide ◽  
Isocitrate Lyase ◽  
Schizophyllum Commune ◽  
Soluble Enzyme ◽  
Basidiomycetous Fungus ◽  
Lyase Activity

The activity of the enzyme, isocitrate lyase, was repressed in glucose cultures of Schizophyllum commune and derepressed in acetate-grown mycelium of this basidiomycetous fungus. The maximum acetate-derepressed level of this soluble enzyme was comparable in individual homokaryotic mycelium or in the dikaryon. Addition of CO2, NaHCO3, or CaCO3 did not significantly derepress isocitrate lyase activity in glucose-cultures. Neither normal dikaryotic fruiting nor its inhibition by carbon dioxide resulted in marked and sustained changes in isocitrate lyase. Thus, a fluctuation in isocitrate lyase activity does not appear to be the salient response of S. commune to increased CO2 tension.

scholarly journals A direct pathway for the conversion of propionate into pyruvate in Moraxella lwoffi

1968 ◽  
Vol 107 (1) ◽  
pp. 7-18 ◽  
Author(s):  
B. Hodgson ◽  
J. D. McGarry
Keyword(s):  
Carbon Dioxide ◽  
Nitrogen Source ◽  
Open System ◽  
Closed System ◽  
Isocitrate Lyase ◽  
Endogenous Respiration ◽  
Reserve Material ◽  
Propionate Metabolism ◽  
Cell Material ◽  
Lyase Activity

1. The identity of the organism previously known as Vibrio O1 (N.C.I.B. 8250) with a species of Moraxella is established. 2. The ability of cells to oxidize propionate is present only in cells with an endogenous respiration and this ability is increased 80-fold when the organism is grown with propionate. 3. Isocitrate lyase activity in extracts from propionate-grown cells is the same as that in extracts from lactate-grown cells, about tenfold greater than that in extracts from succinate-grown cells and slightly greater than half the activity in extracts from acetate-grown cells. 4. With arsenite as an inhibitor conditions were found in which the organism would catalyse the quantitative oxidation of propionate to pyruvate. When propionate was completely utilized pyruvate was metabolized further to 2-oxoglutarate. 5. The oxidation of propionate by cells was incomplete both in a ‘closed system’ with alkali to trap respiratory carbon dioxide and in an ‘open system’ with an atmosphere of oxygen+carbon dioxide (95:5). Acetate accumulated. Under these conditions [2−14C]- and [3−14C]-propionate gave rise to [14C]acetate. The rate of conversion of [2−14C]propionate into 14CO2, although much less than the rate of conversion of [1−14C]propionate into 14CO2, was slightly greater than the rate of conversion of [3−14C]propionate into 14CO2. 6. The oxidation of propionate by cells was complete in an ‘open system’ with an atmosphere of either oxygen or air. Under these conditions very little [1−14C]propionate was converted into 14C-labelled cell material. The conversion of [2−14C]- and [3−14C]-propionate into 14C-labelled cell material occurred at an appreciable rate, the rate for the incorporation of [3−14C]propionate being slightly more rapid. In the absence of a utilizable nitrogen source part of the [14C]propionate was incorporated into some reserve material, which was oxidized when added substrate had been completely utilized. 7. [14C]-Pyruvate produced from [14C]propionate was chemically degraded. The C(1) of propionate was found only in C(1) of pyruvate. At least 86% of C(2) of pyruvate was derived from C(2) of propionate and at least 92% of C(3) of pyruvate from C(3) of propionate. 8. These results are incompatible with the operation of any of the previously described pathways for propionate metabolism except the direct one, perhaps via an activated acrylate.

scholarly journals Isocitrate Lyase Activity in Lactobacillus murinus CNRZ 313

1983 ◽  
Vol 66 (6) ◽  
pp. 1232-1236 ◽  
Author(s):  
M.C. Albizzatti de Rivadeneira ◽  
M.C. Manca de Nadra ◽  
A.A. Pesce de Ruiz Holgado ◽  
G. Oliver
Keyword(s):  
Isocitrate Lyase ◽  
Lyase Activity ◽  
Lactobacillus Murinus

Acetate metabolism in Escherichia coli

1978 ◽  
Vol 24 (2) ◽  
pp. 149-153 ◽  
Author(s):  
T. M. Lakshmi ◽  
Robert B. Helling
Keyword(s):  
Isocitrate Dehydrogenase ◽  
Citrate Synthase ◽  
Isocitrate Lyase ◽  
Glyoxylate Cycle ◽  
Acetate Metabolism ◽  
Wild Type ◽  
Intermediary Metabolites ◽  
Lyase Activity ◽  
Acetate Medium ◽  
The Glyoxylate Cycle

Levels of several intermediary metabolites were measured in cells grown in acetate medium in order to test the hypothesis that the glyoxylate cycle is repressed by phosphoenolpyruvate (PEP). Wild-type cells had less PEP than either isocitrate dehydrogenase – deficient cells (which had greater isocitrate lyase activity than the wild type) or isocitrate dehydrogenase – deficient, citrate synthase – deficient cells (which are poorly inducible). Thus induction of the glyoxylate cycle is more complicated than a simple function of PEP concentration. No correlation between enzyme activity and the level of oxaloacetate, pyruvate, or citrate was found either. Citrate was synthesized in citrate synthase – deficient mutants, possibly via citrate lyase.

Ethmoido-maxillary sinusitis caused by the basidiomycetous fungus Schizophyllum commune

Mycoses ◽  
2011 ◽  
pp. no-no
Author(s):  
C. Lorentz ◽  
A. Rivier ◽  
A. Debourgogne ◽  
J. Sokolowska-Gillois ◽  
J-M. Vignaud ◽  
...  
Keyword(s):  
Maxillary Sinusitis ◽  
Schizophyllum Commune ◽  
Basidiomycetous Fungus

Metabolism of Food Reserves in Germinating Velvetleaf

Weed Science ◽  
1970 ◽  
Vol 18 (5) ◽  
pp. 565-571
Author(s):  
J. A. Mulliken ◽  
C. A. Kust ◽  
L. E. Schrader
Keyword(s):  
Hydrogen Cyanide ◽  
Isocitrate Lyase ◽  
Dry Weight ◽  
Maximal Activity ◽  
Radicle Growth ◽  
Fat Mobilization ◽  
Lyase Activity ◽  
Radicle Emergence ◽  
Weight Protein ◽  
Food Reserves

Endosperm dry weight, protein, and fat losses accompanied rapid radicle growth of velvetleaf (Abutilon theophrasti Medic.) between 12 and 36 hr of germination at 31 C. Cotyledonary reserves were mobilized after 36 hr. Isocitrate lyase activity sedimented with a particulate fraction in varying degrees, but maximal activity developed at times coincident with fat mobilization. Respiration of excised endosperms reached maximal rates shortly after radicle emergence. The actions of hydrogen cyanide, carbon monoxide, and 2,4-dinitrolphenol indicated that respiration of endosperms excised from imbibed and germinated seed was due to cytochrome oxidase activity, and was coupled to phosphorylation.

scholarly journals The Saccharomyces cerevisiae ICL2 Gene Encodes a Mitochondrial 2-Methylisocitrate Lyase Involved in Propionyl-Coenzyme A Metabolism

2000 ◽  
Vol 182 (24) ◽  
pp. 7007-7013 ◽  
Author(s):  
Marijke A. H. Luttik ◽  
Peter Kötter ◽  
Florian A. Salomons ◽  
Ida J. van der Klei ◽  
Johannes P. van Dijken ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Nitrogen Source ◽  
Coenzyme A ◽  
Isocitrate Lyase ◽  
Significant Activity ◽  
Mrna Levels ◽  
Wild Type ◽  
Cell Extracts ◽  
Lyase Activity ◽  
Null Mutants

ABSTRACT The Saccharomyces cerevisiae ICL1 gene encodes isocitrate lyase, an essential enzyme for growth on ethanol and acetate. Previous studies have demonstrated that the highly homologousICL2 gene (YPR006c) is transcribed during the growth of wild-type cells on ethanol. However, even when multiple copies are introduced, ICL2 cannot complement the growth defect oficl1 null mutants. It has therefore been suggested thatICL2 encodes a nonsense mRNA or nonfunctional protein. In the methylcitrate cycle of propionyl-coenzyme A metabolism, 2-methylisocitrate is converted to succinate and pyruvate, a reaction similar to that catalyzed by isocitrate lyase. To investigate whetherICL2 encodes a specific 2-methylisocitrate lyase, isocitrate lyase and 2-methylisocitrate lyase activities were assayed in cell extracts of wild-type S. cerevisiae and of isogenicicl1, icl2, and icl1 icl2 null mutants. Isocitrate lyase activity was absent in icl1 andicl1 icl2 null mutants, whereas in contrast, 2-methylisocitrate lyase activity was detected in the wild type and single icl mutants but not in the icl1 icl2mutant. This demonstrated that ICL2 encodes a specific 2-methylisocitrate lyase and that the ICL1-encoded isocitrate lyase exhibits a low but significant activity with 2-methylisocitrate. Subcellular fractionation studies and experiments with an ICL2-green fluorescent protein fusion demonstrated that theICL2-encoded 2-methylisocitrate lyase is located in the mitochondrial matrix. Similar to that of ICL1, transcription of ICL2 is subject to glucose catabolite repression. In glucose-limited cultures, growth with threonine as a nitrogen source resulted in a ca. threefold induction ofICL2 mRNA levels and of 2-methylisocitrate lyase activity in cell extracts relative to cultures grown with ammonia as the nitrogen source. This is consistent with an involvement of the 2-methylcitrate cycle in threonine catabolism.

Apparent isocitrate lyase activity in Leishmania amazonensis

2017 ◽  
Vol 62 (4) ◽  
Author(s):  
Concepción Hernández-Chinea ◽  
Laura Maimone ◽  
Yelitza Campos ◽  
Walter Mosca ◽  
Pedro J. Romero
Keyword(s):  
Isocitrate Lyase ◽  
Glyoxylate Cycle ◽  
Leishmania Amazonensis ◽  
Lyase Activity

AbstractEarly reports have demonstrated the occurrence of glyoxylate cycle enzymes in several

Incomplete Glyoxysomes Appearing at a Late Stage of Maturation of Cucumber Seeds

1979 ◽  
Vol 34 (12) ◽  
pp. 1232-1236 ◽  
Author(s):  
Wolfram Koller ◽  
Jürgen Frevert ◽  
Helmut Kindi
Keyword(s):  
Late Stage ◽  
Citrate Synthase ◽  
De Novo ◽  
Density Gradient Centrifugation ◽  
Isocitrate Lyase ◽  
Gradient Centrifugation ◽  
Protein Body ◽  
Electrophoretic Analysis ◽  
Malate Synthase ◽  
Lyase Activity

Seeds of cucumber fruits at a late stage of ripening were analyzed for microbodies and micro­body components. On isopycnic density gradient centrifugation of homogenates in the presence of EDTA, several particulate fractions were obtained: a light membraneous fraction (density d = 1.09-1.11 kg × 1-1), a mitochondria-enriched fraction (d = 1.21 kg × 1-1), a microbody-enriched fraction (d = 1.23 kg × 1-1), and a protein body fraction (d= 1.26 - 1.29 kg × 1-1). Microbo­dies were revealed by exactly coinciding peaks of malate synthase, catalase and crotonase; small proportions of citrate synthase and malate dehydrogenase were also present in this zone. Isocitrate lyase activity, however, did not occur in the seeds at this stage. The examination of enzyme activi­ties indicated the presence of microbodies which cannot function as competent glyoxysomes be­cause of the lack of isocitrate lyase. Moreover, de novo synthesis from [3H] leucine could be de­monstrated for malate synthase by means of immunoprecipitation of newly synthesized malate synthase and subsequent electrophoretic analysis.

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