scholarly journals Elucidating the antimycobacterial mechanism of action of ciprofloxacin using metabolomics

2021 ◽  
Author(s):  
Kirsten Elke Knoll ◽  
Zander Lindeque ◽  
Adeniji Ayodele Adetomiwa ◽  
Carel Oosthuizen ◽  
Namrita Lall ◽  
...  
Keyword(s):  
Cell Wall ◽  
Glyoxylate Cycle ◽  
Tricarboxylic Acid ◽  
Pentose Phosphate ◽  
Glycerol Metabolism ◽  
Metabolic Profiles ◽  
Triacylglycerol Metabolism ◽  
Glucose Accumulation ◽  
Statistical Approaches ◽  
Tof Ms

In the interest of developing more effective and safer anti-Tuberculosis treatment, we aimed for a better understanding of the antimycobacterial action of ciprofloxacin against Mycobacterium tuberculosis (Mtb). We used GCxGC-TOF-MS and well described metabolomics statistical approaches, to investigate and compare the metabolic profiles of Mtb in the presence and absence of the drug. The metabolites that best describe the differences between the compared groups were identified as markers characterizing the changes induced by ciprofloxacin. Malic acid was ranked as the most significantly altered metabolite marker induced by ciprofloxacin, indicative of an inhibition of the tricarboxylic acid (TCA) and glyoxylate cycle of Mtb. The altered fatty acid, myo-inositol and triacylglycerol metabolism seen in this group, supports the previous observations of ciprofloxacin action on the Mtb cell wall. Furthermore, the altered pentose phosphate intermediates, glycerol metabolism markers, glucose accumulation, and the reduction in the glucogenic amino acids specifically, indicates a flux towards DNA (as well as cell wall) repair, also supporting previous findings of DNA damage caused by ciprofloxacin. This study further provides insights useful for designing network whole-system strategies for the identification of possible modes of actions of various drugs and possibly adaptations by Mtb resulting in resistance.

scholarly journals Elucidating the Antimycobacterial Mechanism of Action of Ciprofloxacin Using Metabolomics

2021 ◽  
Vol 9 (6) ◽  
pp. 1158
Author(s):  
Kirsten E. Knoll ◽  
Zander Lindeque ◽  
Adetomiwa A. Adeniji ◽  
Carel B. Oosthuizen ◽  
Namrita Lall ◽  
...  
Keyword(s):  
Cell Wall ◽  
Glyoxylate Cycle ◽  
Tricarboxylic Acid ◽  
Pentose Phosphate ◽  
Glycerol Metabolism ◽  
Research Approach ◽  
Metabolic Profiles ◽  
Triacylglycerol Metabolism ◽  
Glucose Accumulation ◽  
Tof Ms

In the interest of developing more effective and safer anti-tuberculosis drugs, we used a GCxGC-TOF-MS metabolomics research approach to investigate and compare the metabolic profiles of Mtb in the presence and absence of ciprofloxacin. The metabolites that best describe the differences between the compared groups were identified as markers characterizing the changes induced by ciprofloxacin. Malic acid was ranked as the most significantly altered metabolite marker induced by ciprofloxacin, indicative of an inhibition of the tricarboxylic acid (TCA) and glyoxylate cycle of Mtb. The altered fatty acid, myo-inositol, and triacylglycerol metabolism seen in this group supports previous observations of ciprofloxacin action on the Mtb cell wall. Furthermore, the altered pentose phosphate intermediates, glycerol metabolism markers, glucose accumulation, as well as the reduction in the glucogenic amino acids specifically, indicate a flux toward DNA (as well as cell wall) repair, also supporting previous findings of DNA damage caused by ciprofloxacin. This study further provides insights useful for designing network whole-system strategies for the identification of possible modes of action of various drugs and possibly adaptations by Mtb resulting in resistance.

scholarly journals Metabolic phases during the development of granulation tissue

1967 ◽  
Vol 105 (1) ◽  
pp. 333-341 ◽  
Author(s):  
Kirsti Lampiaho ◽  
E. Kulonen
Keyword(s):  
Granulation Tissue ◽  
Collagen Synthesis ◽  
Tricarboxylic Acid Cycle ◽  
Tricarboxylic Acid ◽  
Pentose Phosphate ◽  
Acid Cycle ◽  
Short Period ◽  
Tricarboxylic Acid Cycle Intermediates ◽  
Observation Period

1. The metabolism of incubated slices of sponge-induced granulation tissue, harvested 4–90 days after the implantation, was studied with special reference to the capacity of collagen synthesis and to the energy metabolism. Data are also given on the nucleic acid contents during the observation period. Three metabolic phases were evident. 2. The viability of the slices for the synthesis of collagen was studied in various conditions. Freezing and homogenization destroyed the capacity of the tissue to incorporate proline into collagen. 3. Consumption of oxygen reached the maximum at 30–40 days. There was evidence that the pentose phosphate cycle was important, especially during the phases of the proliferation and the involution. The formation of lactic acid was maximal at about 20 days. 4. The capacity to incorporate proline into collagen hydroxyproline in vitro was limited to a relatively short period at 10–30 days. 5. The synthesis of collagen was dependent on the supply of oxygen and glucose, which latter could be replaced in the incubation medium by other monosaccharides but not by the metabolites of glucose or tricarboxylic acid-cycle intermediates.

scholarly journals Whole-Genome Transcriptional Profiling of Bradyrhizobium japonicum during Chemoautotrophic Growth

2008 ◽  
Vol 190 (20) ◽  
pp. 6697-6705 ◽  
Author(s):  
William L. Franck ◽  
Woo-Suk Chang ◽  
Jing Qiu ◽  
Masayuki Sugawara ◽  
Michael J. Sadowsky ◽  
...  
Keyword(s):  
Bradyrhizobium Japonicum ◽  
Carbon Fixation ◽  
Cultured Cells ◽  
Isocitrate Lyase ◽  
Nitrogenase Activity ◽  
Glyoxylate Cycle ◽  
Transcriptional Profiling ◽  
Pentose Phosphate ◽  
Hydrogen Gas ◽  
Essential Components

ABSTRACT Bradyrhizobium japonicum is a facultative chemoautotroph capable of utilizing hydrogen gas as an electron donor in a respiratory chain terminated by oxygen to provide energy for cellular processes and carbon dioxide assimilation via a reductive pentose phosphate pathway. A transcriptomic analysis of B. japonicum cultured chemoautotrophically identified 1,485 transcripts, representing 17.5% of the genome, as differentially expressed when compared to heterotrophic cultures. Genetic determinants required for hydrogen utilization and carbon fixation, including the uptake hydrogenase system and components of the Calvin-Benson-Bassham cycle, were strongly induced in chemoautotrophically cultured cells. A putative isocitrate lyase (aceA; blr2455) was among the most strongly upregulated genes, suggesting a role for the glyoxylate cycle during chemoautotrophic growth. Addition of arabinose to chemoautotrophic cultures of B. japonicum did not significantly alter transcript profiles. Furthermore, a subset of nitrogen fixation genes was moderately induced during chemoautotrophic growth. In order to specifically address the role of isocitrate lyase and nitrogenase in chemoautotrophic growth, we cultured aceA, nifD, and nifH mutants under chemoautotrophic conditions. Growth of each mutant was similar to that of the wild type, indicating that the glyoxylate bypass and nitrogenase activity are not essential components of chemoautotrophy in B. japonicum.

scholarly journals The GC-TOF/MS-based Metabolomic Analysis Reveals Altered Metabolic Profiles in Nitrogen-Deficient Leaves and Roots of Tea Plants (Camellia sinensis L.)

2021 ◽  
Author(s):  
Zheng-He Lin ◽  
Chang-Song Chen ◽  
Qiu-Sheng Zhong ◽  
Qi-Chun Ruan ◽  
Zhi-Hui Chen ◽  
...  
Keyword(s):  
Amino Acids ◽  
Organic Acids ◽  
N Fertilizer ◽  
Metabolic Profiles ◽  
Tea Leaves ◽  
N Deficiency ◽  
Leaves And Roots ◽  
Tea Plants ◽  
Potential Biomarkers ◽  
Tof Ms

Abstract Background: Nitrogen (N) fertilizer is commonly considered as one of the most omportant limiting factors in the agricultural production. As a result, modern tea production, a large amount of N fertilizer is used to improve the yield. Unfortunately, the large amount of N fertilizer input has led to increased plant nitrogen-tolerance and decreased amplitude of yield improvement, which results in significant N loss, energy waste and environment pollution.However, the effects of N-deficiency on the metabolic profiles of leaves and roots are not well understood.Results: In the study, seedlings of Camellia sinensis (L.) O. Kuntze cv. Chunlv 2 were treated with 3 mM NH4NO3（as Control）or without NH4NO3（as N-deficiency）for 4 months by sandy culture. The results suggested the N-deficiency induced tea leaf chlorosis, impaired biomass accumulation, decreased the leaf chlorophyll content and N absorption compared to Control. The untargeted metabolomics based on GC-TOF/MS approach revealed discrimination of the metabolic profiles between N-deficient tea leaves and roots. The identification and classification of the altered metabolites indicated the N deficiency upregulated the relative abundances of most phenylpropanoids, organic acids while downregulated the relative abundances of most amino acids in the tea leaves. Differentially, N-deficiency induced the accumulation of most carbohydrates, organic acids and amino acids in the tea roots. The potential biomarkers screened in the N-deficient leaves compared to Control reflected the N deficiency reduced the tea quality. Unlike the N-deficient leaves, the potential biomarkers in the N-deficient roots implied an improved stress response. Conclusions:The results demonstrated the N deficiency had different effects on the primary and secondary metabolic alteration of tea leaves and roots. The findings of the study will facilitate a comprehensive understanding of the N-deficient tea plants and provide a valuable reference for the optimized N nutrient management in the tea plantations.

Carbohydrate metabolism in Acanthamoeba castellanii. 1. The activity of key enzymes and [14C]-glucose metabolism

1973 ◽  
Vol 19 (9) ◽  
pp. 1131-1136 ◽  
Author(s):  
Lansing M. Prescott ◽  
Harold E. Hoyme ◽  
Darlene Crockett ◽  
Elena Hui
Keyword(s):  
Carbohydrate Metabolism ◽  
Citrate Synthase ◽  
Tricarboxylic Acid Cycle ◽  
Fumarate Hydratase ◽  
Acanthamoeba Castellanii ◽  
Tricarboxylic Acid ◽  
Pentose Phosphate ◽  
Acid Cycle ◽  
Key Enzymes ◽  
Glyceraldehydephosphate Dehydrogenase

The specific activities of a number of the key enzymes involved in carbohydrate metabolism in Acanthamoeba castellanii (Neff clone I–12) have been determined. The following Embden–Meyerhof and pentose phosphate pathway enzymes were present: glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, hexokinase, phosphofructokinase, hexose diphosphatase, aldolase, glyceraldehydephosphate dehydrogenase, pyruvate kinase, and pyruvate-phosphate dikinase. The following tricarboxylic acid cycle enzymes were also found: citrate synthase, aconitase, isocitrate dehydrogenase, succinate dehydrogenase, fumarate hydratase, and malate dehydrogenase. The degradation of glucose-U-14C to 14CO2 was examined. Aerobic 14CO2 production from glucose-U-14C was 3.4-fold greater than anaerobic production. The data provide further evidence that the Embden–Meyerhof, pentose phosphate, and tricarboxylic acid cycle pathways are probably functional in A. castellanii.

Metabolism of glucose-14C, pyruvate-14C, and mannitol-14C by Melampsora lini. II. Conversion to soluble products

1968 ◽  
Vol 46 (4) ◽  
pp. 453-460 ◽  
Author(s):  
D. Mitchell ◽  
Michael Shaw
Keyword(s):  
Pentose Phosphate Pathway ◽  
Tricarboxylic Acid Cycle ◽  
Rust Fungus ◽  
Tca Cycle ◽  
Tricarboxylic Acid ◽  
Pentose Phosphate ◽  
Soluble Carbohydrates ◽  
Melampsora Lini ◽  
Carbohydrate Fraction ◽  
The Tca Cycle

Mycelium of the flax rust fungus (Melampsora lini (Pers.) Lév.), grown on flax cotyledons in tissue culture, had a mean [Formula: see text]of 4.1 and a mean C6/C1 ratio of 0.14, measured after 4 hours in radioactive glucose. The C6/C1 ratio increased with time and also after treatment with 10−5 M 2,4-dinitrophenol. The relative labelling of the (80%) ethanol-soluble carbohydrates, and organic and amino acid fractions after incubation with glucose-1-, -2-, or -6-14C also indicated preferential release of C1 as 14CO2. Trehalose (unknown A) was tentatively identified in the carbohydrate fraction and was mildly radioactive after incubation of the mycelium with labelled glucose for 3 hours. The principal radioactive products of glucose in this fraction were two unknowns, B and C, which were tentatively identified as mannitol and arabitol. The labelling patterns were consistent with their formation from intermediates of the pentose phosphate pathway. The distribution of radioactivity derived from glucose in alanine, glutamate, and aspartate also indicated that hexose or triose units formed in the pentose phosphate pathway were converted to pyruvate, which either gave rise to alanine or was further oxidized in the tricarboxylic acid cycle. Incubation with pyruvate-1-, -2-, or -3-14C for 3 hours gave rise to 14CO2 and labelled alanine, glutamate, and aspartate in a manner consistent with the operation of the TCA cycle. Mannitol-1-6-14C was not metabolized to any appreciable extent in this period, but did give rise to 14CO2 and to several unidentified compounds in the carbohydrate fraction.

scholarly journals Rewiring of glycerol metabolism in Escherichia coli for effective production of recombinant proteins

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Chung-Jen Chiang ◽  
Yi-Jing Ho ◽  
Mu-Chen Hu ◽  
Yun-Peng Chao
Keyword(s):  
Escherichia Coli ◽  
Crude Glycerol ◽  
Metabolic Flux ◽  
Raw Materials ◽  
Tricarboxylic Acid Cycle ◽  
Cost Effective ◽  
Fold Increase ◽  
Pentose Phosphate ◽  
Glycerol Metabolism ◽  
Related Field

Abstract Background The economic viability of a protein-production process relies highly on the production titer and the price of raw materials. Crude glycerol coming from the production of biodiesel is a renewable and cost-effective resource. However, glycerol is inefficiently utilized by Escherichia coli. Results This issue was addressed by rewiring glycerol metabolism for redistribution of the metabolic flux. Key steps in central metabolism involving the glycerol dissimilation pathway, the pentose phosphate pathway, and the tricarboxylic acid cycle were pinpointed and manipulated to provide precursor metabolites and energy. As a result, the engineered E. coli strain displayed a 9- and 30-fold increase in utilization of crude glycerol and production of the target protein, respectively. Conclusions The result indicates that the present method of metabolic engineering is useful and straightforward for efficient adjustment of the flux distribution in glycerol metabolism. The practical application of this methodology in biorefinery and the related field would be acknowledged.

scholarly journals Glucose metabolism and its regulation in pieces of perirenal adipose tissue from foetal lambs

1983 ◽  
Vol 210 (3) ◽  
pp. 677-683 ◽  
Author(s):  
J P Robertson ◽  
A Faulkner ◽  
R G Vernon
Keyword(s):  
Adipose Tissue ◽  
Glucose Metabolism ◽  
Pyruvate Dehydrogenase ◽  
Glucose Utilization ◽  
Tricarboxylic Acid Cycle ◽  
Tricarboxylic Acid ◽  
Pentose Phosphate ◽  
Acid Cycle ◽  
Near Term ◽  
Glucose 6 Phosphate Dehydrogenase

1. The following were measured in pieces of perirenal adipose tissue obtained from foetal lambs at about 120 days of gestation or within 3 days of term, and 9-month-old sheep: the rates of synthesis from glucose of fatty acids, acylglycerol glycerol, pyruvate and lactate; the rate of glucose oxidation to CO2 and the proportions contributed by the pentose phosphate cycle, pyruvate dehydrogenase and the tricarboxylic acid cycle; the activities of hexokinase, glucose 6-phosphate dehydrogenase, phosphofructokinase, pyruvate kinase and pyruvate dehydrogenase. 2. The total rate of glucose utilization was lower in pieces of adipose tissue from near-term lambs than 120-day foetal lambs and the pattern of glucose metabolism differed, with, for example, a much smaller proportion of glucose carbon being used for fatty acid synthesis, whereas a greater proportion of glucose oxidation occurred via the tricarboxylic acid cycle in the near-term lambs. In general, these differences in glucose metabolism were not associated with differences in the activities of the various enzymes listed above. 3. The rates of glucose utilization per fat-cell by 120-day foetal lambs and 9-month-old sheep were very similar but, again, the proportions metabolized to the various products differed. In particular, there was a smaller proportion of glucose oxidized via the pentose phosphate cycle and a greater proportion oxidized via pyruvate dehydrogenase and the tricarboxylic acid cycle in adipose tissue from foetal lambs. These differences were matched by a lower activity of glucose 6-phosphate dehydrogenase and a higher pyruvate dehydrogenase activity in fat-cells from the foetal lambs.

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