• Journal of Microbiology and Biotechnology
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• v.27 no.9
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• pp.1681-1691
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• 2017

This study investigated the effect of proline addition on the salt tolerance of Tetragenococcus halophilus. Salt stress led to the accumulation of intracellular proline in T. halophilus. When 0.5 g/l proline was added to hyperhaline medium, the biomass increased 34.6% (12% NaCl) and 27.7% (18% NaCl) compared with the control (without proline addition), respectively. A metabolomic approach was employed to reveal the cellular metabolic responses and protective mechanisms of proline upon salt stress. The results showed that both the cellular membrane fatty acid composition and metabolite profiling responded by increasing unsaturated and cyclopropane fatty acid proportions, as well as accumulating some specific intracellular metabolites (environmental stress protector). Higher contents of intermediates involved in glycolysis, the tricarboxylic acid cycle, and the pentose phosphate pathway were observed in the cells supplemented with proline. In addition, addition of proline resulted in increased concentrations of many organic osmolytes, including glutamate, alanine, citrulline, N-acetyl-tryptophan, and mannitol, which may be beneficial for osmotic homeostasis. Taken together, results in this study suggested that proline plays a protective role in improving the salt tolerance of T. halophilus by regulating the related metabolic pathways.

• Journal of Veterinary Science
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• v.19 no.6
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• pp.798-807
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• 2018

Several studies have reported the effect of absorption of procyanidins and their contribution to the small intestine. However, differences between dietary interventions of procyanidins and interventions via antibiotic feeding in pigs are rarely reported. Following 16S rRNA gene Illumina MiSeq sequencing, we observed that both procyanidin administration for 2 months (procyanidin-1 group) and continuous antibiotic feeding for 1 month followed by procyanidin for 1 month (procyanidin-2 group) increased the number of operational taxonomic units, as well as the Chao 1 and ACE indices, compared to those in pigs undergoing antibiotic administration for 2 months (antibiotic group). The genera Fibrobacter and Spirochaete were more abundant in the antibiotic group than in the procyanidin-1 and procyanidin-2 groups. Principal component analysis revealed clear separations among the three groups. Additionally, using the online Molecular Ecological Network Analyses pipeline, three co-occurrence networks were constructed; Lactobacillus was in a co-occurrence relationship with Trichococcus and Desulfovibrio and a co-exclusion relationship with Bacillus and Spharerochaeta. Furthermore, metabolic function analysis by phylogenetic investigation of communities by reconstruction of unobserved states demonstrated modulation of pathways involved in the metabolism of carbohydrates, amino acids, energy, and nucleotides. These data suggest that procyanidin influences the gut microbiota and the intestinal metabolic function to produce beneficial effects on metabolic homeostasis.

• Journal of Microbiology and Biotechnology
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• v.34 no.4
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• pp.978-984
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• 2024

Genome-scale metabolic model (GEM) can be used to simulate cellular metabolic phenotypes under various environmental or genetic conditions. This study utilized the GEM to observe the internal metabolic fluxes of recombinant Escherichia coli producing gamma-aminobutyric acid (GABA). Recombinant E. coli was cultivated in a fermenter under three conditions: pH 7, pH 5, and additional succinic acids. External fluxes were calculated from cultivation results, and internal fluxes were calculated through flux optimization. Based on the internal flux analysis, glycolysis and pentose phosphate pathways were repressed under cultivation at pH 5, even though glutamate dehydrogenase increased GABA production. Notably, this repression was halted by adding succinic acid. Furthermore, proper sucA repression is a promising target for developing strains more capable of producing GABA.

• Journal of KIISE:Software and Applications
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• v.36 no.11
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• pp.875-890
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• 2009

Metabolimics interprets an organism as a network of functional units and an organism is represented by a metabolic pathway i.e., well-displayed graph. So a software tool for drawing pathway is necessary to understand it comprehensively. These tools have a problem that edge-crossings exponentially increase as the number of nodes grows. To apply automatic graph layout techniques to the genome-scale metabolic flow, it is very important to reduce unnecessary edge-crossing on a metabolic pathway layout. In this paper, we design and implement 2.5D metabolic pathway layout modules. Metabolic pathways are represented hierarchically by making use of the '2-layered layout algorithm' in 3D. It enhances the readability and reduces unnecessary edge-crossings by using 3D layout modules instead of 2D layout algorithms.

• BMB Reports
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• v.54 no.2
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• pp.124-129
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• 2021

In current times, obesity is a major health problem closely associated with metabolic disease such as diabetes, dyslipidemia, and cardiovascular disease. The direct cause of obesity is known as an abnormal increase in fat cell size and the adipocyte pool. Hyperplasia, the increase in number of adipocytes, results from adipogenesis in which preadipocytes differentiate into mature adipocytes. Adipogenesis is regulated by local and systemic cues that alter transduction pathways and subsequent control of adipogenic transcription factors. Therefore, the regulation of adipogenesis is an important target for preventing obesity. Myonectin, a member of the CTRP family, is a type of myokine released by skeletal muscle cells. Although several studies have shown that myonectin is associated with lipid metabolism, the role of myonectin during adipogenesis is not known. Here, we demonstrate the role of myonectin during adipocyte differentiation of 3T3-L1 cells. We found that myonectin inhibits the adipogenesis of 3T3-L1 preadipocytes with a reduction in the expression of adipogenic transcription factors such as C/EBPα, β and PPARγ. Furthermore, we show that myonectin has an inhibitory effect on adipogenesis through the regulation of the p38 MAPK pathway and CHOP. These findings suggest that myonectin may be a novel therapeutic target for the prevention of obesity.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.4
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• pp.187-193
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• 2005

Several signal transduction pathways have been implicated in ischemic preconditioning induced by the activation of ATP-sensitive $K^+$ $(K_{ATP})$ channels. We examined whether protein kinase C (PKC) modulated the activity of $K_{ATP}$ channels by recording $K_{ATP}$ channel currents in rabbit ventricular myocytes using patch-clamp technique and found that phorbol 12,13-didecanoate (PDD) enhanced pinacidil-induced $K_{ATP}$ channel activity in the cell-attached configuration; and this effect was prevented by bisindolylmaleimide (BIM). $K_{ATP}$ channel activity was not increased by $4{\alpha}-PDD$. In excised insideout patches, PKC stimulated $K_{ATP}$ channels in the presence of 1 mM ATP, and this effect was abolished in the presence of BIM. Heat-inactivated PKC had no effect on channel activity. PKC-induced activation of $K_{ATP}$ channels was reversed by PP2A, and this effect was not detected in the presence of okadaic acid. These results suggest that PKC activates $K_{ATP}$ channels in rabbit ventricular myocytes.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3963-3969
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• 2016

Purpose:To assess IGFBP-6 expression in relation with the presence of the metabolic syndrome, adiponectin receptors (AdipoR1 and AdipoR2) and IGF-IR levels in colorectal adenocarcinoma cases. Materials and Methods: IGFBP-6 mRNA and protein levels were analyzed using real-time quantitative PCR and Western blotting in 46 patients. ELISA and flow cytometry were used for evaluation of AdipoR1, AdipoR2 and IGF-IR. Results: The results showed that IGFBP-6 mRNA expression and the IGFBP-6 content were higher in tumor tissue samples of colorectal cancer patients with tahtn without metabolic syndrome. In addition, the IGFBP-6 mRNA expression was associated with tumor invasion (tumor size) and the IGFBP-6 protein level was associated with nodal status. Positive correlations and positive nonlinear relations were found between the IGFBP-6 level and the AdipoR1 and AdipoR2 contents in colorectal cancer patients. Conclusions: The IGFBP-6 mRNA level and protein level were found to be associated with presence of metabolic syndrome. Positive correlations indicated probable cross-talk between the IGF-IR-mediated and adiponectin-mediated signaling pathways in colorectal carcinomas. IGFBP-6 may be considered as a potential biomarker associated with lymphogenous metastasis and the metabolic syndrome in colorectal cancer.

• Molecules and Cells
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• v.40 no.9
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• pp.685-695
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• 2017

Obesity and the metabolic disorders that constitute metabolic syndrome are a primary cause of morbidity and mortality in the world. Nonetheless, the changes in the proteins and the underlying molecular pathways involved in the relevant pathogenesis are poorly understood. In this study a proteomic analysis of the visceral adipose tissue isolated from metabolically healthy and unhealthy obese patients was used to identify presence of altered pathway(s) leading to metabolic dysfunction. Samples were obtained from 18 obese patients undergoing bariatric surgery and were subdivided into two groups based on the presence or absence of comorbidities as defined by the International Diabetes Federation. Two dimensional difference in-gel electrophoresis coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was carried out. A total of 28 proteins were identified with a statistically significant difference in abundance and a 1.5-fold change (ANOVA, $p{\leq}0.05$) between the groups. 11 proteins showed increased abundance while 17 proteins were decreased in the metabolically unhealthy obese compared to the healthy obese. The differentially expressed proteins belonged broadly to three functional categories: (i) protein and lipid metabolism (ii) cytoskeleton and (iii) regulation of other metabolic processes. Network analysis by Ingenuity pathway analysis identified the $NF{\kappa}B$, IRK/MAPK and PKC as the nodes with the highest connections within the connectivity map. The top network pathway identified in our protein data set related to cellular movement, hematological system development and function, and immune cell trafficking. The VAT proteome between the two groups differed substantially between the groups which could potentially be the reason for metabolic dysfunction.

• International Journal of Oral Biology
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• v.42 no.3
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• pp.85-90
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• 2017

Mitochondria participate in various intracellular metabolic pathways such as generating intracellular ATP, synthesizing several essential molecules, regulating calcium homeostasis, and producing the cell's reactive oxygen species (ROS). Emerging studies have demonstrated newly discovered roles of mitochondria, which participate in the regulation of innate immune responses by modulating NLRP3 inflammasomes. Here, we review the recently proposed pathways to be involved in mitochondria-mediated regulation of inflammasome activation and inflammation: 1) mitochondrial ROS, 2) calcium mobilization, 3) nicotinamide adenine dinucleotide ($NAD^+$) reduction, 4) cardiolipin, 5) mitofusin, 6) mitochondrial DNA, 7) mitochondrial antiviral signaling protein. Furthermore, we highlight the significance of mitophagy as a negative regulator of mitochondrial damage and NLRP3 inflammasome activation, as potentially helpful therapeutic approaches which could potentially address uncontrolled inflammation.

• Journal of Microbiology and Biotechnology
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• v.28 no.7
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• pp.1037-1051
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• 2018

The genus Rhodococcus is a phylogenetically and catabolically diverse group that has been isolated from diverse environments, including polar and alpine regions, for its versatile ability to degrade a wide variety of natural and synthetic organic compounds. Their metabolic capacity and diversity result from their diverse catabolic genes, which are believed to be obtained through frequent recombination events mediated by large catabolic plasmids. Many rhodococci have been used commercially for the biodegradation of environmental pollutants and for the biocatalytic production of high-value chemicals from low-value materials. Recent studies of their physiology, metabolism, and genome have broadened our knowledge regarding the diverse biotechnological applications that exploit their catabolic enzymes and pathways.