scholarly journals Metabolomic analysis of biosynthesis mechanism of ε-polylysine produced by Streptomyces diastatochromogenes

2020 ◽  
Author(s):  
Ziyuan Wang ◽  
Fengzhu Guo ◽  
Tianyu Dong ◽  
Zhilei Tan ◽  
Mohamed Abdelraof ◽  
...  
Keyword(s):  
Metabolic Regulation ◽  
Absorption Capacity ◽  
High Yield ◽  
Regulation Mechanism ◽  
Original Strain ◽  
Metabolomic Analysis ◽  
Streptomyces Sp ◽  
Activity Of Enzymes ◽  
The Difference ◽  
Branched Chain

Abstract ε-polylysine (ε-PL) is a polypeptide that shows broad-spectrum inhibition against both Gram-positive and Gram-negative bacteria, and it’s mainly produced by Streptomyces sp. However, the biosynthesis mechanism of ε-PL by Streptomyces sp. is still unclear. Herein, the metabolomic analysis of the biosynthesis mechanism of ε-PL in the original strain TUST and the high-yield mutant strain 6#-7 were investigated. Results show that the difference on metabolisms between TUST and 6#-7 was significant during fermentation periods. And based on further analyses of the results of both metabolomics and enzymatic activity, a possible metabolic regulation mechanism of the high-yield mutagenized strain 6#-7 was proposed. The transport and absorption capacity for glucose of strain 6#-7 is improved. And the activity of enzymes relating to ε-PL synthesis, including Hexokinase (HK) et al., is strengthened. On the contrary, the activity of enzymes in the branched-chain pathways, such as Succinate dehydrogenase (SDH) et al. is decreased. Meanwhile, the increase of trehalose, glutamic acid and proline makes the strain 6#-7 more resistant to ε-PL. Moreover, the strain 6#-7 has stronger ability to transfer ε-PL out the cell. Thus the ability of the mutagenized strain to synthesize ε-PL is enhanced and the strain 6#-7 can produce more ε-PL compared with the original strain. These findings provide a theoretical basis for further improving the production of ε-PL.

scholarly journals Metabolomic Analysis of Biosynthesis Mechanism of ε-Polylysine Produced by Streptomyces diastatochromogenes

2021 ◽  
Vol 9 ◽  
Author(s):  
Ziyuan Wang ◽  
Fengzhu Guo ◽  
Tianyu Dong ◽  
Zhilei Tan ◽  
Mohamed Abdelraof ◽  
...  
Keyword(s):  
Metabolic Regulation ◽  
Absorption Capacity ◽  
High Yield ◽  
Regulation Mechanism ◽  
Original Strain ◽  
Metabolomic Analysis ◽  
Homoserine Dehydrogenase ◽  
Yield Strain ◽  
The Difference ◽  
Branched Chain

ε-Polylysine (ε-PL), a natural preservative with broad-spectrum antimicrobial activity, has been widely used as a green food additive, and it is now mainly produced by Streptomyces in industry. In the previous study, strain 6#-7 of high-yield ε-PL was obtained from the original strain TUST by mutagenesis. However, the biosynthesis mechanism of ε-PL in 6#-7 is still unclear. In this study, the metabolomic analyses of the biosynthesis mechanism of ε-PL in both strains are investigated. Results show that the difference in metabolisms between TUST and 6#-7 is significant. Based on the results of both metabolomic and enzymatic activities, a metabolic regulation mechanism of the high-yield strain is revealed. The transport and absorption capacity for glucose of 6#-7 is improved. The enzymatic activity benefits ε-PL synthesis, such as pyruvate kinase and aspartokinase, is strengthened. On the contrary, the activity of homoserine dehydrogenase in the branched-chain pathways is decreased. Meanwhile, the increase of trehalose, glutamic acid, etc. makes 6#-7 more resistant to ε-PL. Thus, the ability of the mutagenized strain 6#-7 to synthesize ε-PL is enhanced, and it can produce more ε-PLs compared with the original strain. For the first time, the metabolomic analysis of the biosynthesis mechanism of ε-PL in the high-yield strain 6#-7 is investigated, and a possible mechanism is then revealed. These findings provide a theoretical basis for further improving the production of ε-PL.

scholarly journals Analysis of Metabolite Accumulation Related to Pod Color Variation of Caragana intermedia

Molecules ◽  
2019 ◽  
Vol 24 (4) ◽  
pp. 717
Author(s):  
Feiyun Yang ◽  
Tianrui Yang ◽  
Kun Liu ◽  
Qi Yang ◽  
Yongqing Wan ◽  
...  
Keyword(s):  
Metabolic Regulation ◽  
Ion Trap ◽  
Shikimic Acid ◽  
Color Variation ◽  
Regulation Mechanism ◽  
Metabolic Pathway Analysis ◽  
Caragana Intermedia ◽  
The Difference ◽  
Different Color ◽  
Auxin Accumulation

Caragana intermedia, a leguminous shrub widely distributed in cold and arid regions, is rich in secondary metabolites and natural active substances, with high nutritional and medical values. It is interesting that the pods of C. intermedia often show different colors among individual plants. In this study, 10-, 20- and 30-day-old red and green pods of C. intermedia were used to identify and characterize important metabolites associated with pod color. A total 557 metabolites, which could be classified into 21 groups, were detected in the pod extracts using liquid chromatography coupled with ESI-triple quadrupole-linear ion trap mass spectrometer (LC-ESI-MS/MS). Metabolomics analysis revealed significant differences in 15 groups of metabolites between red and green pods, including amino acids, nucleotide derivatives, flavonoids, and phytohormones. Metabolic pathway analysis showed that the shikimic acid and the phytohormone metabolic pathways were extraordinarily active in red pods, and the difference between red and green pods was obvious. Moreover, red pods showed remarkable flavonoids, cytokinins, and auxin accumulation, and the content of total flavonoids and proanthocyanidins in 30-day-old red pods was significantly higher than that in green pods. This metabolic profile contributes to valuable insights into the metabolic regulation mechanism in different color pods.

Synthesis of Starch-Graft-Polyacrylamide by Salt Solution Media Polymerization

2012 ◽  
Vol 557-559 ◽  
pp. 1049-1052
Author(s):  
Wen Bing Li ◽  
Ting Ting Huang ◽  
Guang Hua Wang
Keyword(s):  
Salt Solution ◽  
Synthesis Method ◽  
Monomer Conversion ◽  
High Yield ◽  
Solution System ◽  
Raw Starch ◽  
Polymerization System ◽  
Product Loss ◽  
The Difference ◽  
Branched Chain

Starch-graft-polyacrylamide (St-g-PAM) was prepared using a salt media polymerization technique, and characterized by FITR. The type of starch and the synthesis method of different system were studied through the mass of product, the percentage of grafting (PG) and the monomer conversion (MC), and the difference polymerization system. The results showed that the pretreated starch and the salt solution system, respectively, were more advantageous than the raw starch and the aqueous solution system. The intrinsic viscosity, transmittance, product loss, penetration and apparent viscosity of St-g-PAM by salt solution polymerization were 12.49 dL•g-1, 18.6%, 0.56%, 53.96, 18.40 Pa•S, respectively. The method could get bigger branched-chain molecular than the others with high yield, high monomer conversion, high the percentage of grafting, low product losses and easy post-processing

scholarly journals Metabolomic Analysis of the Effects of Leptin Replacement Therapy in Patients with Lipodystrophy

2019 ◽  
Vol 4 (1) ◽  
Author(s):  
Shivraj Grewal ◽  
Sriram Gubbi ◽  
Andin Fosam ◽  
Caroline Sedmak ◽  
Shanaz Sikder ◽  
...  
Keyword(s):  
Replacement Therapy ◽  
Glucose Tolerance Test ◽  
Tolerance Test ◽  
Oral Glucose ◽  
Oral Glucose Tolerance ◽  
Metabolomic Analysis ◽  
Metabolomic Profiling ◽  
Branched Chain Amino Acid ◽  
Before And After ◽  
Branched Chain

Abstract Context and Objective Leptin treatment has dramatic clinical effects on glucose and lipid metabolism in leptin-deficient patients with lipodystrophy. Further elucidation of metabolic effects of exogenous leptin therapy will shed light on understanding leptin physiology in humans. Our objective was to utilize metabolomic profiling to examine the changes associated with administration of short-term metreleptin therapy in patients with lipodystrophy. Study Design We conducted a pre-post-treatment study in 19 patients (75% female) with varying forms of lipodystrophy (congenital generalized lipodystrophy, n = 10; acquired generalized lipodystrophy, n = 1; familial partial lipodystrophy, n = 8) who received daily subcutaneous metreleptin injections for a period of 16 to 23 weeks. A 3-hour oral glucose tolerance test and body composition measurements were conducted before and after the treatment period, and fasting blood samples were used for metabolomic profiling. The study outcome aimed at measuring changes in physiologically relevant metabolites before and after leptin therapy. Results Metabolomic analysis revealed changes in pathways involving branched-chain amino acid metabolism, fatty acid oxidation, protein degradation, urea cycle, tryptophan metabolism, nucleotide catabolism, vitamin E, and steroid metabolism. Fold changes in pre- to post-treatment metabolite levels indicated increased breakdown of fatty acids, branched chain amino acids proteins, and nucleic acids. Conclusions Leptin replacement therapy has significant effects on important metabolic pathways implicated in patients with lipodystrophy. Continued metabolomic studies may provide further insight into the mechanisms of action of leptin replacement therapy and provide novel biomarkers of lipodystrophy. Abbreviations: 1,5-AG, 1,5-anhydroglucitol; 11βHSD1, 11-β hydroxysteroid dehydrogenase 1; BCAA, branched-chain amino acid; FFA, free fatty acid; GC-MS, gas chromatography mass spectrometry; IDO, indoleamine 2,3-dioxygenase; IFN-γ, interferon-γ; m/z, mass to charge ratio; OGTT, oral glucose tolerance test; TDO, tryptophan 2,3-dioxygenase; TNF-α, tumor necrosis factor-α; UPLC-MS/MS, ultra-performance liquid chromatography-tandem mass spectrometry.

scholarly journals Causes Of Yield Gaps And Strategies For Minimizing The Gaps In Different Crops Of Bangladesh

1970 ◽  
Vol 36 (3) ◽  
pp. 469-476 ◽  
Author(s):  
Mohammad H Mondal
Keyword(s):  
New Technologies ◽  
High Yield ◽  
Credit System ◽  
Yield Gap ◽  
Related Factors ◽  
Integrated Crop Management ◽  
Yield Gaps ◽  
The Difference ◽  
The Government ◽  
Extension Agencies

The concept of yield gaps originated from the studies conducted by IRRI in the seventies. The yield gap discussed in this paper is the difference between the potential farm yield and the actual average farm yield. In Bangladesh, yield gaps exist in different crops ranging up to 60%. According to the recent study conducted by BRRI, the yield gap in rice was estimated at 1.74 t/ha. The existence of yield gaps was as well observed in rice, mustard, wheat and cotton in India. In India, yield gap varied from 15.5 to 60% with the national average gap of 52.3% in irrigated ecosystem. The yield gaps are mainly caused by biological, socio-economic, climate and institutional/policy related factors. Different strategies, such as integrated crop management (1CM) practices, timely supply of inputs including credit to farmers, research and extension collaboration to transfer the new technologies have been discussed as strategies to minimize yield gaps. Suggestions have been made to make credit available to resource-poor small farmers to buy necessary inputs. Reducing transaction cost, simplifying lending procedures and strengthening monitoring mechanism of the current credit system are, however, essential to enable the farmers to avail the credit facility. Efforts should be made to update farmers’ knowledge on the causes of yield gaps in crops and measures to narrow the gaps through training, demonstrations, field visits and monitoring by extension agencies to achieve high yield. The government should realize that yield gaps exist in different crops of Bangladesh and therefore, explore the scope to increase production as well as productivity of crops by narrowing the yield gap and thereby ensure food security. Keywords: Yield gaps; strategies; crops of Bangladesh. DOI: http://dx.doi.org/10.3329/bjar.v36i3.9274 BJAR 2011; 36(3): 469-476

Activation of branched-chain keto acid dehydrogenase by exercise

1985 ◽  
Vol 248 (2) ◽  
pp. R166-R171 ◽  
Author(s):  
G. J. Kasperek ◽  
G. L. Dohm ◽  
R. D. Snider
Keyword(s):  
Dehydrogenase Activity ◽  
Metabolic Regulation ◽  
Exercise Bout ◽  
Total Activity ◽  
Activity Levels ◽  
Keto Acid ◽  
Leucine Oxidation ◽  
Basal Activity ◽  
Acid Dehydrogenase ◽  
Branched Chain

The present study was conducted to investigate the metabolic regulation of leucine oxidation during exercise. Ten rats per group were run at 27 m/min (0% grade) on a treadmill for 30 and 120 min or until exhausted, and the total and basal activity of branched-chain keto acid dehydrogenase was examined in the muscle, liver, and heart. The total activity of the dehydrogenase in the heart, liver, or skeletal muscle was unchanged by exercise. However, exercise increased the basal activity levels of the dehydrogenase about 10-fold in muscle and 5-fold in heart. The basal dehydrogenase activity in the liver was unchanged by exercise. Activation of the dehydrogenase in both muscle and heart was statistically elevated after 30 min exercise and continued to increase during the remainder of the exercise bout. The basal activity of the dehydrogenase returned to resting levels by 10 min postexercise. The activation of the dehydrogenase in muscle and heart during exercise likely is due to dephosphorylation because activity of the enzyme in mitochondria isolated from exercised muscles reverts to control values when the mitochondria are incubated in the presence of ATP. Thus the increased leucine oxidation observed during exercise is due to activation of the branched-chain keto acid dehydrogenase by dephosphorylation. This is the first example of a large increase in branched-chain keto acid dehydrogenase activity caused by a physiological process. This demonstrates that the muscle's latent capacity of oxidize branched-chain amino acids is much larger than previously thought and that this capacity is used in exercising muscle.

scholarly journals Differences in xylem development between Dutch and Japanese tomato (Solanum lycopersicum) correlate with cytokinin levels in hypocotyls

2020 ◽  
Vol 126 (2) ◽  
pp. 315-322 ◽  
Author(s):  
Xiaohua Qi ◽  
Hirokazu Takahashi ◽  
Yasushi Kawasaki ◽  
Yuya Ohta ◽  
Masahide Isozaki ◽  
...  
Keyword(s):  
High Yield ◽  
Growth Stages ◽  
Cytokinin Biosynthesis ◽  
Xylem Development ◽  
Isopentenyl Adenine ◽  
Use Efficiency ◽  
The Difference ◽  
Leaf Photosynthetic Rate ◽  
The Relationship ◽  
Different Growth Stages

Abstract Background and Aims Dutch tomato cultivars tend to have a greater yield than Japanese cultivars even if they are grown under the same conditions. Factors contributing to the increased yield of the Dutch cultivars were a greater light use efficiency and greater leaf photosynthetic rate. On the other hand, the relationship between tomato yields and anatomical traits is still unclear. The aim of this study is to identify the anatomical traits related to the difference in yield between Dutch and Japanese cultivars. Methods Anatomical properties were compared during different growth stages of Dutch and Japanese tomatoes. Hormone profiles and related gene expression in hypocotyls of Dutch and Japanese cultivars were compared in the hypocotyls of 3- and 4-week-old plants. Key results Dutch cultivars have a more developed secondary xylem than Japanese cultivars, which would allow for greater transport of water, mineral nutrients and phytohormones to the shoots. The areas and ratios of the xylem in the hypocotyls of 3- to 6-week-old plants were larger in the Dutch cultivars. In reciprocal grafts of the Japanese and Dutch cultivars, xylem development at the scion and rootstock depended on the scion cultivar, suggesting that some factors in the scion are responsible for the difference in xylem development. The cytokinin content, especially the level of N6-(Δ 2-isopentenyl) adenine (iP)-type cytokinin, was higher in the Dutch cultivars. This result was supported by the greater expression of Sl-IPT3 (a cytokinin biosynthesis gene) and Sl-RR16/17 (a cytokinin-responsive gene) in the Dutch cultivars. Conclusions These results suggest that iP-type cytokinins, which are locally synthesized in the hypocotyl, contribute to xylem development. The greater xylem development in Dutch cultivars might contribute to the high yield of the tomato.

New Route to Branched-chain Aminodeoxy Sugars by Reaction of Ketoses with Acetonitrile. Synthesis of Methyl 3-C-2′-Aminoethyl-2-deoxy-α-D-arabino-hexopyranoside

1974 ◽  
Vol 52 (1) ◽  
pp. 51-54 ◽  
Author(s):  
Alex Rosenthal ◽  
G. Schöllnhammer
Keyword(s):  
Catalytic Hydrogenation ◽  
Liquid Ammonia ◽  
High Yield ◽  
Lithium Amide ◽  
Branched Chain

Addition of methyl 4,6-O-benzylidene-2-deoxy-α-D-erythro-hexopyranosid-3-ulose (1) to acetonitrile in liquid ammonia at −50 to −60° in the presence of lithium amide gave, in high yield, crystalline methyl 4,6-O-benzylidene-3-C-cyanomethyl-2-deoxy-α-D-arabino-hexopyranoside (2) exclusively. The proof of structure 2 is described. Debenzylidenation of 2 afforded the branched-chain cyano glycoside 3. Compound 3 was converted into its 3,4,6-tri-O-acetate (8) and 4,6-di-O-p-nitrobenzoate (9) derivatives. Catalytic hydrogenation of 3 over rhodium on alumina yielded methyl 3-C-2′-aminoethyl-2-deoxy-α-D-arabino-hexopyranoside which was characterized as its N-2,4-dinitrophenyl derivative (7).

Quasi-Static and Dynamic Axial Crushing of Various Polygonal Tubes

2007 ◽  
Vol 340-341 ◽  
pp. 1399-1404 ◽  
Author(s):  
Minoru Yamashita ◽  
Toshio Hattori ◽  
Naoya Nishimura ◽  
Y. Tange
Keyword(s):  
Circular Tube ◽  
Axial Direction ◽  
Plastic Property ◽  
Absorption Capacity ◽  
Deformation Pattern ◽  
Explicit Finite Element ◽  
Collapse Mode ◽  
The Difference ◽  
Dynamic Loading Conditions ◽  
Crush Strength

Various polygonal tubes were compressed in the axial direction under quasi-static and dynamic loading conditions. The effect of the polygonal shape and the wall thickness on the crush behavior is investigated, in which the cyclic buckling takes place. The numbers of polygonal edges were 3, 4, 5, 6 and 7 in the experiment. A circular tube was also tested for comparison. The tubes were machined from aluminum alloy A5056 bar. Crush strength is estimated as an index of the energy absorption capacity of the tube. It increases with increasing the number of polygonal edges of the tube, although it almost saturates when the number of polygonal edges is more than 6. For the wider variety of polygonal tubes than that in the experiment, numerical simulation is performed using the dynamic explicit finite element code DYNA3D. The computed crush behavior well agrees with the corresponding experimental one, however, the difference in collapse mode arises due to the slight imperfections in experiment. The deformation pattern becomes more irregular for the thinner-walled tube. Further, it is presumed that the large hardening exponent in the plastic property of the material could prevent the buckling switching from the symmetric mode to asymmetric one in the crushing of circular tube.

Sign in / Sign up

Export Citation Format

Share Document