Constitutive nature of the enzymes of citrate metabolism inStreptococcus lactissubsp.diacetylactis

1981 ◽  
Vol 48 (3) ◽  
pp. 489-495 ◽  
Author(s):  
Timothy M. Cogan
Keyword(s):  
Acetolactate Synthase ◽  
Streptococcus Lactis ◽  
Citrate Metabolism ◽  
Citrate Lyase ◽  
In Cells

SummaryFour enzymes of citrate metabolism (viz. citrate lyase, acetolactate synthase, diacetyl reductase and acetoin reductase) were constitutively present in cells of several strains ofStreptococcus lactissubsp.diacetylactis. In strain DRC1, which was studied in detail, diacetyl reductase and acetoin reductase were partly repressed and acetolactate synthase partly induced by growth on citrate. The stage of growth also affected the formation of each enzyme. The buffer species affected the activity of acetolactate synthase, diacetyl reductase and acetoin reductase.

Citrate metabolism by Enterococcus faecium and Enterococcus durans isolated from goat’s and ewe’s milk: influence of glucose and lactose

2007 ◽  
Vol 53 (5) ◽  
pp. 607-615 ◽  
Author(s):  
María E. Cabral ◽  
María C. Abeijón Mukdsi ◽  
Roxana B. Medina de Figueroa ◽  
Silvia N. González
Keyword(s):  
Energy Source ◽  
Enterococcus Faecium ◽  
Specific Activity ◽  
Acetolactate Synthase ◽  
Acetate Kinase ◽  
Enterococcus Durans ◽  
Flavour Compounds ◽  
Citrate Metabolism ◽  
Citrate Lyase ◽  
Sole Energy

Citrate metabolism by Enterococcus faecium ET C9 and Enterococcus durans Ov 421 was studied as sole energy source and in presence of glucose or lactose. Both strains utilized citrate as the sole energy source. Enterococcus faecium ET C9 showed diauxic growth in the presence of a limiting concentration of glucose. Neither strain used citrate until glucose was fully metabolized. The strains showed co-metabolism of citrate and lactose. Lactate, acetate, formate, and flavour compounds (diacetyl, acetoin, and 2,3-butanediol) were detected in both strains. The highest production of flavour compounds was detected during growth of E. durans Ov 421 in media supplemented with citrate–glucose and citrate–lactose. Citrate lyase was inducible in both strains. Acetate kinase activities presented the highest values in LAPTc medium, with E. faecium ET C9 displaying a specific activity 2.4-fold higher than E. durans. The highest levels of α-acetolactate synthase specific activity were detected in E. durans grown in LAPTc+g, in accordance with the maximum production of flavour compounds detected in this medium. Diacetyl and acetoinreductases displayed lower specific activity values in the presence of citrate. Enterococcus faecium and E. durans displayed citrate lyase, acetate kinase, α-acetolactate synthase, and diacetyl and acetoin reductase activities. These enzymes are necessary for conversion of citrate to flavour compounds that are important in fermented dairy products.

Induction of some enzymes of citrate metabolism inLeuconostoc lactisand other heterofermentative lactic acid bacteria

1981 ◽  
Vol 48 (3) ◽  
pp. 497-502 ◽  
Author(s):  
Dervla Mellerick ◽  
Timothy M. Cogan
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Acetolactate Synthase ◽  
Citrate Metabolism ◽  
Citrate Lyase ◽  
Leuconostoc Lactis

SummaryCitrate stimulated growth, totally induced citrate lyase, partly induced acetolactate synthase activity and partly repressed both diacetyl and acetoin reductases inLeuconostoc lactisNCW1. Similar results were obtained with 2 other leuconostocs and a heterofermentative lactobacillus. In 2 of the 3 leuconostocs tested, diacetyl reductase and acetoin reductase were NADPH specific, while in the 2 heterofermentative lactobacilli, they were NADH specific.

scholarly journals Transcriptional Changes in Cancer Cells Induced by Exposure to a Healing Method

Dose-Response ◽  
2018 ◽  
Vol 16 (3) ◽  
pp. 155932581878284 ◽  
Author(s):  
Sarah Beseme ◽  
William Bengston ◽  
Dean Radin ◽  
Michael Turner ◽  
John McMichael
Keyword(s):  
Cancer Cells ◽  
Atp Citrate Lyase ◽  
Expression Of Genes ◽  
Citrate Lyase ◽  
Hands On ◽  
Transcriptional Changes ◽  
Cancer And Inflammation ◽  
Delivery Technology ◽  
In Cells

Energy healing, or healing with intent, is a complementary and alternative medicine therapy reported to be beneficial with a wide variety of conditions. We are developing a delivery technology for a method previously tested in mouse models with solid tumors (the Bengston method) independent of the presence of a healer. The goal of this study was to assess whether stored or recorded energy has an impact on breast cancer cells in vitro, using energy-charged cotton and electromagnetic recording of healers practicing the method. Expression of genes involved in cancer and inflammation pathways was measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Treatment of cells using energy-charged cotton resulted in statistically significant changes <1.5-fold. In cells exposed to an electromagnetic recording, 37 genes of 167 tested showed a >1.5-fold change when compared to the control, and 68 genes showing statistically significant fold changes. Two genes, ATP citrate lyase ( ACLY) and interleukin 1β ( IL-1β), were consistently downregulated at 4 and 24 hours of exposure to the recording, respectively, in 3 independent experiments. Both ACLY and IL-1β were also downregulated in cells exposed to a hands-on delivery of the method, suggesting these 2 genes as potential markers of the healing method.

scholarly journals Ca2+-Citrate Uptake and Metabolism in Lactobacillus casei ATCC 334

2013 ◽  
Vol 79 (15) ◽  
pp. 4603-4612 ◽  
Author(s):  
Pablo Mortera ◽  
Agata Pudlik ◽  
Christian Magni ◽  
Sergio Alarcón ◽  
Juke S. Lolkema
Keyword(s):  
Metal Ion ◽  
Lactobacillus Casei ◽  
Acetolactate Synthase ◽  
Metabolic Energy ◽  
Growth Stages ◽  
Resting Cells ◽  
Oxaloacetate Decarboxylase ◽  
Content Type ◽  
Citrate Metabolism ◽  
Membrane Bound

ABSTRACTThe putative citrate metabolic pathway inLactobacillus caseiATCC 334 consists of the transporter CitH, a proton symporter of the citrate-divalent metal ion family of transporters CitMHS, citrate lyase, and the membrane-bound oxaloacetate decarboxylase complex OAD-ABDH. Resting cells ofLactobacillus caseiATCC 334 metabolized citrate in complex with Ca2+and not as free citrate or the Mg2+-citrate complex, thereby identifying Ca2+-citrate as the substrate of the transporter CitH. The pathway was induced in the presence of Ca2+and citrate during growth and repressed by the presence of glucose and of galactose, most likely by a carbon catabolite repression mechanism. The end products of Ca2+-citrate metabolism by resting cells ofLb. caseiwere pyruvate, acetate, and acetoin, demonstrating the activity of the membrane-bound oxaloacetate decarboxylase complex OAD-ABDH. Following pyruvate, the pathway splits into two branches. One branch is the classical citrate fermentation pathway producing acetoin by α-acetolactate synthase and α-acetolactate decarboxylase. The other branch yields acetate, for which the route is still obscure. Ca2+-citrate metabolism in a modified MRS medium lacking a carbohydrate did not significantly affect the growth characteristics, and generation of metabolic energy in the form of proton motive force (PMF) was not observed in resting cells. In contrast, carbohydrate/Ca2+-citrate cometabolism resulted in a higher biomass yield in batch culture. However, also with these cells, no generation of PMF was associated with Ca2+-citrate metabolism. It is concluded that citrate metabolism inLb. caseiis beneficial when it counteracts acidification by carbohydrate metabolism in later growth stages.

Cytoplasmic Tubules in Cells Infected with Laryngotracheitis Virus

1969 ◽  
Vol 27 ◽  
pp. 376-377
Author(s):  
A. M. Watrach
Keyword(s):  
Tissue Culture ◽  
Small Proportion ◽  
Chicken Embryo ◽  
Culture Cells ◽  
Tissue Culture Cells ◽  
Morphologic Characteristics ◽  
Infectious Laryngotracheitis ◽  
Laryngotracheitis Virus ◽  
In Cells

During a study of the development of infectious laryngotracheitis (LT) virus in tissue culture cells, unusual tubular formations were found in the cytoplasm of a small proportion of the affected cells. It is the purpose of this report to describe the morphologic characteristics of the tubules and to discuss their possible association with the development of virus.The source and maintenance of the strain of LT virus have been described. Prior to this study, the virus was passed several times in chicken embryo kidney (CEK) tissue culture cells.

Effect of Some Metabolic Inhibitors on Vinblastine-Induced Ribosomal-Granular Material Complexes

1971 ◽  
Vol 29 ◽  
pp. 548-549
Author(s):  
Awtar Krishan ◽  
Dora Hsu
Keyword(s):  
Granular Material ◽  
Rna Synthesis ◽  
Culture Medium ◽  
Actinomycin D ◽  
Metabolic Inhibitors ◽  
Protein And Rna Synthesis ◽  
Apparent Reduction ◽  
Plant Alkaloids ◽  
In Cells

Cells exposed to antitumor plant alkaloids, vinblastine and vincristine sulfate have large proteinacious crystals and complexes of ribosomes, helical polyribosomes and electron-dense granular material (ribosomal complexes) in their cytoplasm, Binding of H3-colchicine by the in vivo crystals shows that they contain microtubular proteins. Association of ribosomal complexes with the crystals suggests that these structures may be interrelated.In the present study cultured human leukemic lymphoblasts (CCRF-CEM), were incubated with protein and RNA-synthesis inhibitors, p. fluorophenylalanine, puromycin, cycloheximide or actinomycin-D before the addition of crystal-inducing doses of vinblastine to the culture medium. None of these compounds could completely prevent the formation of the ribosomal complexes or the crystals. However, in cells pre-incubated with puromycin, cycloheximide, or actinomycin-D, a reduction in the number and size of the ribosomal complexes was seen. Large helical polyribosomes were absent in the ribosomal complexes of cells treated with puromycin, while in cells exposed to cycloheximide, there was an apparent reduction in the number of ribosomes associated with the ribosomal complexes (Fig. 2).

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