RESUMEN
In hypertrophic scar (HS) formation, the type 2 immune response induces the alternatively activated macrophages (M2), which manipulate fibroblasts to differentiate into myofibroblasts with active biologic functions and proliferation. Myofibroblasts express α-smooth muscle actin (α-SMA) and synthesize and produce additional collagen type I and collagen type III, inducing HS formation. However, studies on the mechanism of M2 macrophage modulation are only based on the recognition of profibrotic factors such as TGF-ß1 secreted by macrophages. The influence of exosomes from M2 macrophages on scar formation is still unknown. Both M2 macrophages and myofibroblasts highly express glutaminases (GLSs). GLS is a critical enzyme in glutaminolysis and is important for M2 macrophage and fibroblast polarization. In this study, we found that in a TGF-ß1-stimulated coculture system, a long noncoding RNA (lncRNA) named lncRNA-ASLNCS5088 was enriched in M2 macrophage-derived exosomes. This lncRNA could be transferred with high efficiency to fibroblasts and acted as an endogenous sponge to adsorb microRNA-200c-3p, resulting in increased GLS and α-SMA expression. Pretreatment with GW4869, which impairs M2 macrophage exosome synthesis, ameliorated these pathologic changes in fibroblasts in vitro. Local injection in the late scar formation period with GW4869 reduced α-SMA+ fibroblasts and alleviated the fibrosis of tissue after wound healing in vivo.-Chen, J., Zhou, R., Liang, Y., Fu, X., Wang, D., Wang, C. Blockade of lncRNA-ASLNCS5088-enriched exosome generation in M2 macrophages by GW4869 dampens the effect of M2 macrophages on orchestrating fibroblast activation.
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Compuestos de Anilina/farmacología , Compuestos de Bencilideno/farmacología , Cicatriz Hipertrófica/etiología , Exosomas/fisiología , Fibroblastos/fisiología , Macrófagos/fisiología , ARN Largo no Codificante/fisiología , Actinas/biosíntesis , Proteínas de la Matriz Extracelular/biosíntesis , Glutaminasa/biosíntesis , Humanos , Células THP-1 , Factor de Crecimiento Transformador beta1/fisiologíaRESUMEN
This article focuses on significant advances in the production and applications of microbial glutaminases and provides insight into the structures of different glutaminases. Glutaminases catalyze the deamidation of glutamine to glutamic acid, and this unique ability forms the basis of their applications in various industries such as pharmaceutical and food organizations. Microbial glutaminases from bacteria, actinomycetes, yeast, and fungi are of greater significance than animal glutaminases because of their stability, affordability, and ease of production. Owing to these notable benefits, they are considered to possess considerable potential in anticancer and antiviral therapy, flavor enhancers in oriental foods, biosensors and in the production of a nutraceutical theanine. This review also aims to fully explore the potential of microbial glutaminases and to set the pace for future prospects.
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Glutaminasa/biosíntesis , Microbiología Industrial/métodos , Animales , Clonación Molecular , Glutaminasa/química , Glutaminasa/genética , Glutaminasa/farmacología , Humanos , Conformación Proteica , Tolerancia a la SalRESUMEN
In this study, the Micrococcus luteus K-3 glutaminase was successfully over-expressed in the GRAS (Generally Recognized as Safe) Bacillus subtilis strain 168 by integration of the Mglu gene in the 16S rDNA locus. This was done in order to screen a strain producing high levels of recombinant glutaminase from the selected candidates. The transcription of the glutaminase genes in the B. subtilis 168 chromosome and the expression of glutaminase protein was further assessed by qPCR, SDS-PAGE analysis and an enzyme activity assay. To further increase the production of glutaminase, the nprB and nprE genes, which encode specific proteases, were disrupted by integration of the Mglu gene. After continuous cell culturing without the addition of antibiotics, the integrated recombinant strains showed excellent genetic stability, demonstrating favorable industrialization potential. After the fermentation temperature was optimized, a 5-L bioreactor was used for fed-batch fermentation of the recombinant glutaminase producing strain at 24 °C, and the highest enzyme activity achieved was approximately 357.6 U/mL.
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Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas Bacterianas/genética , ADN Ribosómico/genética , Endopeptidasas/genética , Fermentación , Glutaminasa/biosíntesis , Regulación Bacteriana de la Expresión Génica , Glutaminasa/metabolismo , TemperaturaRESUMEN
In the course of studies aimed at the role of oxidative stress in the development of metastatic potential in the LNCaP-C4-2B prostate cancer progression model system, we found a relative decrease in the level of expression of the cytoplasmic nicotinamide riboside: quinone oxidoreductase (NQO2) and an increase in the oxidative stress in C4-2B cells compared to that in LNCaP or its derivatives C4 and C4-2. It was also found that C4-2B cells specifically shed large extracellular vesicles (LEVs) suggesting that these LEVs and their cargo could participate in the establishment of the osseous metastases. The level of expression of caveolin-1 increased as the system progresses from LNCaP to C4-2B. Since NQO2 RNA levels were not changed in LNCaP, C4, C4-2, and C4-2B, we tested an altered cellular distribution hypothesis of NQO2 being compartmentalized in the membrane fractions of C4-2B cells which are rich in lipid rafts and caveolae. This was confirmed when the detergent resistant membrane fractions were probed on immunoblots. Moreover, when the LEVs were analyzed for membrane associated caveolin-1 as possible cargo, we noticed that the enzyme NQO2 was also a component of the cargo along with caveolin-1 as seen in double immunofluorescence studies. Molecular modeling studies showed that a caveolin-1 accessible site is present in NQO2. Specific interaction between NQO2 and caveolin-1 was confirmed using deletion constructs of caveolin-1 fused with glutathione S-transferase (GST). Interestingly, whole cell lysate and mitochondrial preparations of LNCaP, C4, C4-2, and C4-2B showed an increasing expression of glutaminase (GLS, kidney type). The extrusion of LEVs appears to be a specific property of the bone metastatic C4-2B cells and this process could be inhibited by a GLS specific inhibitor BPTES, suggesting the critical role of a functioning glutamine metabolism. Our results indicate that a high level of expression of caveolin-1 in C4-2B cells contributes to an interaction between caveolin-1 and NQO2 and to their packaging as cargo in the shed LEVs. These results suggest an important role of membrane associated oxidoreductases in the establishment of osseous metastases in prostate cancer.
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Vesículas Extracelulares/enzimología , Glutaminasa/metabolismo , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/patología , Quinona Reductasas/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Caveolina 1/metabolismo , Línea Celular Tumoral , Progresión de la Enfermedad , Vesículas Extracelulares/metabolismo , Glutaminasa/biosíntesis , Glutamina/metabolismo , Humanos , Immunoblotting , Masculino , Modelos Moleculares , NAD(P)H Deshidrogenasa (Quinona)/biosíntesis , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Metástasis de la Neoplasia , Estrés Oxidativo , Neoplasias de la Próstata/metabolismo , Quinona Reductasas/biosíntesis , Quinona Reductasas/químicaRESUMEN
AIM: to analyze the effect of metformin on ammonia production derived from glutamine metabolism in vitro and in vivo. METHODS: twenty male Wistar rats were studied for 28 days after a porto-caval anastomosis (n = 16) or a sham operation (n = 4). Porto-caval shunted animals were randomized into two groups (n = 8) and either received 30 mg/kg/day of metformin for two weeks or were control animals. Plasma ammonia concentration, Gls gene expression and K-type glutaminase activity were measured in the small intestine, muscle and kidney. Furthermore, Caco2 were grown in different culture media containing glucose/glutamine as the main carbon source and exposed to different concentrations of the drug. The expression of genes implicated in glutamine metabolism were analyzed. RESULTS: metformin was associated with a significant inhibition of glutaminase activity levels in the small intestine of porto-caval shunted rats (0.277 ± 0.07 IU/mg vs 0.142 ± 0.04 IU/mg) and a significant decrease in plasma ammonia (204.3 ± 24.4 µg/dl vs 129.6 ± 16.1 µg/dl). Glucose withdrawal induced the expression of the glutamine transporter SLC1A5 (2.54 ± 0.33 fold change; p < 0.05). Metformin use reduced MYC levels in Caco2 and consequently, SLC1A5 and GLS expression, with a greater effect in cells dependent on glutaminolytic metabolism. CONCLUSION: metformin regulates ammonia homeostasis by modulating glutamine metabolism in the enterocyte, exerting an indirect control of both the uptake and degradation of glutamine. This entails a reduction in the production of metabolites and energy through this pathway and indirectly causes a decrease in ammonia production that could be related to a decreased risk of HE development.
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Glutamina/metabolismo , Encefalopatía Hepática/tratamiento farmacológico , Encefalopatía Hepática/metabolismo , Hipoglucemiantes/uso terapéutico , Metformina/uso terapéutico , Amoníaco/metabolismo , Animales , Células CACO-2 , Preescolar , Glutaminasa/antagonistas & inhibidores , Glutaminasa/biosíntesis , Glutaminasa/genética , Humanos , Masculino , Ratas , Ratas WistarRESUMEN
Unlike short interfering RNAs (siRNAs), which are commonly designed to repress a single messenger RNA (mRNA) target through perfect base pairing, microRNAs (miRNAs) are endogenous small RNAs that have evolved to concurrently repress multiple mRNA targets through imperfect complementarity. MicroRNA target recognition is primarily determined by pairing of the miRNA seed sequence (nucleotides 2-8) to complementary match sites in each mRNA target. Whereas siRNA technology is well established for single target knockdown, the design of artificial miRNAs for multi-target repression is largely unexplored. We designed and functionally analysed over 200 artificial miRNAs for simultaneous repression of pyruvate carboxylase and glutaminase by selecting all seed matches shared by their 3' untranslated regions. Although we identified multiple miRNAs that repressed endogenous protein expression of both genes, seed-based artificial miRNA design was highly inefficient, as the majority of miRNAs with even perfect seed matches did not repress either target. Moreover, commonly used target prediction programs did not substantially discriminate effective artificial miRNAs from ineffective ones, indicating that current algorithms do not fully capture the features important for artificial miRNA targeting and are not yet sufficient for designing artificial miRNAs. Our analysis suggests that additional factors are strong determinants of the efficacy of miRNA-mediated target repression and remain to be discovered.
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Técnicas de Silenciamiento del Gen , MicroARNs/genética , Regiones no Traducidas 3' , Secuencia de Bases , Sitios de Unión , Genes Reporteros , Glutaminasa/biosíntesis , Glutaminasa/genética , Células HEK293 , Humanos , Piruvato Carboxilasa/biosíntesis , Piruvato Carboxilasa/genética , Interferencia de ARNRESUMEN
Glutaminolysis is a crucial factor for tumor metabolism in the carcinogenesis of several tumors but has not been clarified for oral squamous cell carcinoma (OSCC) yet. Expression of glutaminolysis-related solute carrier family 1, member 5 (SLC1A5)/neutral amino acid transporter (ASCT2), glutaminase (GLS), and glutamate dehydrogenase (GLDH) was analyzed in normal oral mucosa (n = 5), oral precursor lesions (simple hyperplasia, n = 11; squamous intraepithelial neoplasia, SIN I-III, n = 35), and OSCC specimen (n = 42) by immunohistochemistry. SLC1A5/ASCT2 and GLS were significantly overexpressed in the carcinogenesis of OSCC compared with normal tissue, while GLDH was weakly detected. Compared with SIN I-III SLC1A5/ASCT2 and GLS expression were significantly increased in OSCC. GLDH expression did not significantly differ from SIN I-III compared with OSCC. This study shows the first evidence of glutaminolysis-related SLC1A5/ASCT2, GLS, and GLDH expression in OSCC. The very weak GLDH expression indicates that glutamine metabolism is rather related to nucleotide or protein/hexosamine biosynthesis or to the function as an antioxidant (glutathione) than to energy production or generation of lactate through entering the tricarboxylic acid cycle. Overcoming glutaminolysis by targeting c-Myc oncogene (e.g. by natural compounds) and thereby cross-activation of mammalian target of rapamycin complex 1 or SLC1A5/ASCT2, GLS inhibitors may be a useful strategy to sensitize cancer cells to common OSCC cancer therapies.
Asunto(s)
Biomarcadores de Tumor/genética , Carcinogénesis/genética , Carcinoma de Células Escamosas/genética , Regulación Neoplásica de la Expresión Génica , Glutamina/genética , Neoplasias de la Boca/metabolismo , ARN Neoplásico/genética , Sistema de Transporte de Aminoácidos ASC/biosíntesis , Animales , Biomarcadores de Tumor/biosíntesis , Carcinogénesis/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Femenino , Glutaminasa/biosíntesis , Glutamina/biosíntesis , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Antígenos de Histocompatibilidad Menor , Mucosa Bucal/metabolismo , Mucosa Bucal/patología , Neoplasias de la Boca/patología , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/biosíntesis , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Active glutamine utilization is critical for tumor cell proliferation. Glutaminolysis represents the first and rate-limiting step of glutamine utilization and is catalyzed by glutaminase (GLS). Activation of ErbB2 is one of the major causes of breast cancers, the second most common cause of death for women in many countries. However, it remains unclear whether ErbB2 signaling affects glutaminase expression in breast cancer cells. In this study, we show that MCF10A-NeuT cell line has higher GLS1 expression at both mRNA and protein levels than its parental line MCF10A, and knockdown of ErbB2 decreases GLS1 expression in MCF10A-NeuT cells. We further show that in these cells, ErbB2-mediated upregulation of GLS1 is not correlated to c-Myc expression. Moreover, activation of neither PI3K-Akt nor MAPK pathway is sufficient to upregulate GLS1 expression. Interestingly, inhibition of NF-κB blocks ErbB2-stimulated GLS1 expression, whereas stimulation of NF-κB is sufficient to enhance GLS1 levels in MCF10A cells, suggesting a PI3K-Akt-independent activation of NF-κB upregulates GLS1 in ErbB2-positive breast cancer cells. Finally, knockdown or inhibition of GLS1 significantly decreased the proliferation of breast cancer cells with high GLS1 levels. Taken together, our data indicate that ErbB2 activation promotes GLS1 expression via a PI3K-Akt-independent NF-κB pathway in breast cancer cells, identifying another oncogenic signaling pathway which stimulates GLS1 expression, and thus promoting glutamine utilization in cancer cells. These findings, if validated by in vivo model, may facilitate the identification of novel biochemical targets for cancer prevention and therapy.
Asunto(s)
Neoplasias de la Mama/genética , Proliferación Celular , Glutaminasa/biosíntesis , Receptor ErbB-2/genética , Apoptosis/genética , Neoplasias de la Mama/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Glutaminasa/genética , Humanos , FN-kappa B/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosforilación , Proteínas Proto-Oncogénicas c-akt/genética , Transducción de SeñalRESUMEN
The Rhesus factor protein, Rh C glycoprotein (Rhcg), is an ammonia transporter whose expression in the collecting duct is necessary for normal ammonia excretion both in basal conditions and in response to metabolic acidosis. Hypokalemia is a common clinical condition associated with increased renal ammonia excretion. In contrast to basal conditions and metabolic acidosis, increased ammonia excretion during hypokalemia can lead to an acid-base disorder, metabolic alkalosis, rather than maintenance of acid-base homeostasis. The purpose of the current studies was to determine Rhcg's role in hypokalemia-stimulated renal ammonia excretion through the use of mice with collecting duct-specific Rhcg deletion (CD-Rhcg-KO). In mice with intact Rhcg expression, a K(+)-free diet increased urinary ammonia excretion and urine alkalinization and concurrently increased Rhcg expression in the collecting duct in the outer medulla. Immunohistochemistry and immunogold electron microscopy showed hypokalemia increased both apical and basolateral Rhcg expression. In CD-Rhcg-KO, a K(+)-free diet increased urinary ammonia excretion and caused urine alkalinization, and the magnitude of these changes did not differ from mice with intact Rhcg expression. In mice on a K(+)-free diet, CD-Rhcg-KO increased phosphate-dependent glutaminase (PDG) expression in the outer medulla. We conclude that hypokalemia increases collecting duct Rhcg expression, that this likely contributes to the hypokalemia-stimulated increase in urinary ammonia excretion, and that adaptive increases in PDG expression can compensate for the absence of collecting duct Rhcg.
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Amoníaco/metabolismo , Proteínas de Transporte de Catión/metabolismo , Hipopotasemia/metabolismo , Túbulos Renales Colectores/metabolismo , Glicoproteínas de Membrana/metabolismo , Acidosis/genética , Acidosis/metabolismo , Amoníaco/orina , Animales , Proteínas de Transporte de Catión/genética , Femenino , Eliminación de Gen , Glutaminasa/biosíntesis , Concentración de Iones de Hidrógeno , Médula Renal/citología , Médula Renal/metabolismo , Túbulos Renales Colectores/citología , Masculino , Glicoproteínas de Membrana/genética , Ratones , Ratones Noqueados , Fosfatos/metabolismo , Fosfatos/orina , Potasio en la Dieta/metabolismo , Potasio en la Dieta/orina , Orina/químicaRESUMEN
Glutaminase or L-glutamine aminohydrolase (EC 3.5.1.2) is an enzyme that catalyzes the formation of glutamic acid and ammonium ion from glutamine. This enzyme functions in cellular metabolism of every organism by supplying nitrogen required for the biosynthesis of a variety of metabolic intermediates, while glutamic acid plays a role in both sensory and nutritional properties of food. So far there have been only a few reports on cloning, expression and characterization of purified glutaminases. Microbial glutaminases are enzymes with emerging potential in both the food and the pharmaceutical industries. In this research a recombinant glutaminase from Bacillus licheniformis (GlsA) was expressed in Escherichia coli, under the control of a ptac promoter. The recombinant enzyme was tagged with decahistidine tag at its C-terminus and could be conveniently purified by one-step immobilized metal affinity chromatography (IMAC) to apparent homogeneity. The enzyme could be induced for efficient expression with IPTG, yielding approximately 26,000 units from 1-l shake flask cultures. The enzyme was stable at 30°C and pH 7.5 for up to 6h, and could be used efficiently to increase glutamic acid content when protein hydrolysates from soy and anchovy were used as substrates. The study demonstrates an efficient expression system for the production and purification of bacterial glutaminase. In addition, its potential application for bioconversion of glutamine to flavor-enhancing glutamic acid has been demonstrated.
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Bacillus/enzimología , Proteínas Bacterianas/biosíntesis , Escherichia coli/genética , Glutaminasa/biosíntesis , Proteínas Recombinantes de Fusión/biosíntesis , Secuencia de Aminoácidos , Bacillus/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Estabilidad de Enzimas , Ácido Glutámico/metabolismo , Glutaminasa/química , Glutaminasa/genética , Glutaminasa/metabolismo , Histidina/genética , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Hidrolisados de Proteína , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Alineación de Secuencia , TemperaturaRESUMEN
Protein-glutaminase (EC 3.5.1.44, PG) converts protein glutamine residues in proteins and peptides into glutamic acid residue, and markedly improves the solubility, emulsification, and foaming properties of food proteins. However, the source bacteria, Chryseobacterium proteolyticum, have low enzyme production ability, inefficient genetic operation, and high production cost. Therefore, it is critical to establish an efficient expression system for active PG. Here, combinatorial engineering was developed for high-yield production of PG in Bacillus subtilis. First, we evaluated different B. subtilis strains for PG self-activation. Then, combinatorial optimization involving promoters, signal peptides, and culture medium was applied to produce active recombinant PG in a B. subtilis expression system. Through combinatorial engineering, PG enzyme activity reached 3.23 U/mL in shaken-flask cultures. Active PG with the yield of 7.07 U/mL was obtained at 40 h by the PSecA-YdeJ combination in fed-batch fermentation, which is the highest yield of PG in existing reports.
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Bacillus subtilis , Proteínas Bacterianas/biosíntesis , Chryseobacterium , Glutaminasa/biosíntesis , Bacillus subtilis/metabolismo , Chryseobacterium/enzimología , Fermentación , Ingeniería de Proteínas , Señales de Clasificación de ProteínaRESUMEN
Protein feeding is known to decrease hunger and subsequent food intake in animals and humans. It has also been suggested that glucose appearance into portal vein, as occurring during meal assimilation, may induce comparable effects. Here, we connect these previous observations by reporting that intestinal gluconeogenesis (i.e., de novo synthesis of glucose) is induced during the postabsorptive time (following food digestion) in rats specifically fed on protein-enriched diet. This results in glucose release into portal blood, counterbalancing the lowering of glycemia resulting from intestinal glucose utilization. Comparable infusions into the portal vein of control postabsorptive rats (fed on starch-enriched diet) decrease food consumption and activate the hypothalamic nuclei regulating food intake. Similar hypothalamic activation occurs on protein feeding. All these effects are absent after denervation of the portal vein. Thus, portal sensing of intestinal gluconeogenesis may be a novel mechanism connecting the macronutrient composition of diet to food intake.
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Proteínas en la Dieta , Ingestión de Alimentos , Gluconeogénesis , Glucosa-6-Fosfatasa/biosíntesis , Glutaminasa/biosíntesis , Intestino Delgado/metabolismo , Fosfoenolpiruvato Carboxiquinasa (GTP)/biosíntesis , Animales , Conducta Animal , Carbohidratos de la Dieta , Inducción Enzimática , Glucosa/metabolismo , Hipotálamo/metabolismo , Vena Porta/inervación , Vena Porta/metabolismo , Periodo Posprandial , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Factores de TiempoRESUMEN
Glutaminase production in Zygosacchromyces rouxii by solid-state fermentation (SSF) is detailed. Substrates screening showed best results with oatmeal (OM) and wheatbran (WB). Further, a 1:1 combination of OM: WB gave 0.614units/gds with artificial sea water (ASW) as moistening agent. Evaluation of additional carbon, nitrogen, aminoacids and minerals supplementation was done. A central composite design was employed to investigate effects of four variables, viz. moisture content, glucose, corn steep liquor and glutamine on production. A 4-fold increase in enzyme production was obtained. Studies were undertaken to analyze the time course model the microbial growth and nutrient utilization during SSF. Logistic equation (R2=0.8973), describing the growth model of Z.rouxii was obtained, with maximum values of micronm and Xm at 0.326h-1 and 7.35% of dry matter weight loss, respectively. A good-fit model to describe utilization of total carbohydrate (R2=0.9906) nitrogen concentration (R2=0.9869) with time was obtained. The model was used successfully to predict enzyme production (R2=0.7950).
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Glutaminasa/biosíntesis , Microbiología Industrial/métodos , Zygosaccharomyces/enzimología , Zygosaccharomyces/crecimiento & desarrollo , Fermentación , Glutaminasa/metabolismo , Modelos Biológicos , Modelos Estadísticos , Zygosaccharomyces/metabolismoRESUMEN
AIM AND OBJECTIVE: To review the applications and production studies of reported antileukemic drug L-glutaminase under Solid-state Fermentation (SSF). OVERVIEW: An amidohydrolase that gained economic importance because of its wide range of applications in the pharmaceutical industry, as well as the food industry, is L-glutaminase. The medical applications utilized it as an anti-tumor agent as well as an antiretroviral agent. L-glutaminase is employed in the food industry as an acrylamide degradation agent, as a flavor enhancer and for the synthesis of theanine. Another application includes its use in hybridoma technology as a biosensing agent. Because of its diverse applications, scientists are now focusing on enhancing the production and optimization of L-glutaminase from various sources by both Solid-state Fermentation (SSF) and submerged fermentation studies. Of both types of fermentation processes, SSF has gained importance because of its minimal cost and energy requirement. L-glutaminase can be produced by SSF from both bacteria and fungi. Single-factor studies, as well as multi-level optimization studies, were employed to enhance L-glutaminase production. It was concluded that L-glutaminase activity achieved by SSF was 1690 U/g using wheat bran and Bengal gram husk by applying feed-forward artificial neural network and genetic algorithm. The highest L-glutaminase activity achieved under SSF was 3300 U/gds from Bacillus sp., by mixture design. Purification and kinetics studies were also reported to find the molecular weight as well as the stability of L-glutaminase. CONCLUSION: The current review is focused on the production of L-glutaminase by SSF from both bacteria and fungi. It was concluded from reported literature that optimization studies enhanced L-glutaminase production. Researchers have also confirmed antileukemic and anti-tumor properties of the purified L-glutaminase on various cell lines.
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Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Fermentación , Glutaminasa/biosíntesis , Glutaminasa/farmacología , Bacterias , Hongos , Humanos , CinéticaRESUMEN
PURPOSE: To screen the novel biomarkers for gastric cancer and to determine the values of glutaminase 1 (GLS1) and gamma-glutamylcyclotransferase (GGCT) for detecting gastric cancer. EXPERIMENTAL DESIGN: A discovery group of four paired gastric cancer tissue samples are labeled with Isobaric tag for relative and absolute quantitation agents and identified with LC-ESI-MS/MS. A validation group of 168 gastric cancer samples and 30 healthy controls are used to validate the expression of GLS1 and GGCT. RESULTS: Four hundred and thirty-one proteins are found differentially expressed in gastric cancer tissues. Of these proteins, GLS1 and GGCT are found overexpressed in gastric cancer patients, with sensitivity of 75.6% (95% CI: 69-82.2%) and specificity of 81% (95% CI: 75-87%) for GLS1, and with sensitivity of 63.1% (95% CI: 55.7-71.5%) and specificity of 60.7% (95% CI: 53.3-68.2%) for GGCT. The co-expression of GLS1 and GGCT in gastric cancer tissues has sensitivity of 78.1% (95% CI: 70.1-86.1%) and specificity of 86.5% (95% CI: 79.5-93.4%). Moreover, both GLS1 and GGCT present higher expression of 82.6% (95% CI: 68.5-99.4%) and 73.9% (95% CI: 54.5-93.3%) in lymph node metastasis specimen than those in non-lymph node metastasis specimen. The areas under ROC curves are up to 0.734 for the co-expression of GLS1 and GGCT in gastric cancer. The co-expression of GLS1 and GGCT is strongly associated with histological grade, lymph node metastasis, and TNM stage â ¢/â £. CONCLUSIONS AND CLINICAL RELEVANCE: The present study provides the quantitative proteomic analysis of gastric cancer tissues to identify prognostic biomarkers of gastric cancer. The co-expression level of GLS1 and GGCT is of great clinical value to serve as diagnostic and therapeutic biomarkers for early gastric cancer.
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Biomarcadores de Tumor/biosíntesis , Regulación del Desarrollo de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Glutaminasa/biosíntesis , Glutamina/metabolismo , Proteínas de Neoplasias/biosíntesis , Neoplasias Gástricas/metabolismo , gamma-Glutamilciclotransferasa/biosíntesis , Cromatografía Liquida , Femenino , Humanos , Masculino , Espectrometría de Masas , Proteómica , Neoplasias Gástricas/patologíaRESUMEN
PURPOSE: We evaluated the expression of glutaminolysis-related proteins in Hurthle cell neoplasms (HCN) and follicular neoplasms (FN) of the thyroid, and investigated its clinical implication. METHODS: Tissue microarrays were constructed from 264 FNs (112 follicular carcinomas [FCs] and 152 follicular adenomas [FAs]) and 108 HCNs (27 Hurthle cell carcinomas [HCCs] and 81 Hurthle cell adenomas [HCAs]. The immunohistochemical staining result of 3 glutaminolysis-related proteins (Glutaminase 1 [GLS1], glutaminate dehydrogenase [GDH] and alanine- serine, cysteine-preferring transporter 2 [ASCT2]) was analyzed. RESULTS: GLS1 and GDH showed significantly higher expression rates in HCN compared to FN (P<0.001). More HCN cases showed co-positivity of multiple glutaminolysis-related proteins than those of FN cases (P<0.001). In silico analysis, both GLUD1 and GLUD2 showed higher expression rate in HCA compared to FA (P=0.027 and P=0.018, respectively). SLC1A5 expression was highest in HCA, followed by FC and FA (HCA vs FC, P=0.023; FC vs FA, P=0.002). CONCLUSION: FN and HCN exhibit a different expression pattern for glutaminolysis-related proteins, and GLS1 and GDH have higher expression rates in HCN and FN.
Asunto(s)
Adenocarcinoma Folicular/metabolismo , Adenoma Oxifílico/metabolismo , Neoplasias de la Tiroides/metabolismo , Adulto , Sistema de Transporte de Aminoácidos ASC/análisis , Sistema de Transporte de Aminoácidos ASC/biosíntesis , Femenino , Glutamato Deshidrogenasa/análisis , Glutamato Deshidrogenasa/biosíntesis , Glutaminasa/análisis , Glutaminasa/biosíntesis , Glutamina/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Antígenos de Histocompatibilidad Menor/análisis , Antígenos de Histocompatibilidad Menor/biosíntesisRESUMEN
A human brain cDNA clone coding for a novel PDZ-domain protein of 124 amino acids was previously isolated in our laboratory. The protein was termed glutaminase-interacting protein (GIP), because it interacts with the C-terminal region of the human L-type glutaminase (LGA). The pattern of expression and functions of GIP in brain are completely unknown, so its significance remains undefined. Here we describe the expression of GIP mRNA and protein in mammalian brain. Northern blot analysis revealed that GIP mRNA was ubiquitous in most regions of human brain but was particularly abundant in spinal cord. The presence of the protein in rat and monkey brain was studied at the regional, cellular, and subcellular level by immunocytochemistry. The protein was found to be present in both neurons and astrocytes, with a cytosolic and mitochondrial subcellular localization. Double immunofluorescence labeling with anti-GIP and anti-LGA antibodies using confocal microscopy revealed colocalization of both proteins in astrocyte cell processes and their perivascular end feet. Electron microscopy of rat brain neurons revealed GIP immunoreactivity concentrated also in the nuclear envelope and the plasma membrane. The multiple locations for GIP in mammalian brain are in agreement with known protein interaction partners reported for this PDZ protein. The findings presented here support a role of GIP as an important scaffold in both astrocytes and neurons and point toward astrocytic processes and perivascular end feet as plausible anatomical substrates for interaction with glutaminase.
Asunto(s)
Astrocitos/metabolismo , Encéfalo/metabolismo , Glutaminasa/biosíntesis , Neuronas/metabolismo , Animales , Northern Blotting , Western Blotting , Expresión Génica , Haplorrinos , Humanos , Inmunohistoquímica , Péptidos y Proteínas de Señalización Intracelular , Ratones , Microscopía Confocal , Microscopía Inmunoelectrónica , ARN Mensajero/análisis , Ratas , Médula Espinal/metabolismoRESUMEN
Microbial anti-cancer enzymes have been proven to be effective and economical agents for cancer treatment. Aeromonas veronii has been identified as a microorganism with the potential to produce L-glutaminase, an anticancer agent effective against acute lymphocytic leukaemia. In this study, a selective medium of Aeromonas veronii was used to culture the microorganism. Strain improvement was done by adaptive and induced mutational techniques. A selective minimal agar media was incorporated for the growth of the strain which further supports adaptive mutation. Strains were also UV-irradiated and successively treated with N-methyl-N'-nitro-N-nitrosoguanidine to find a resilient strain capable of producing L-glutaminase efficiently. The Plackett-Burman design and central composite designs were used to screen and optimize additional carbon and nitrogen sources. Adaptive mutation resulted in promising yield improvements compared to native strain (P<0.001). The mean yield of 30 treated colonies from the induced mutation was significantly increased compared to the non-induced strain (P< 0.001). The economically feasible statistical designs were found to reinforce each other in order to maximize the yield of the enzyme. The interactions of nutrient factors were understood from the 3D response surface plots. The model was found to be a perfect fit in terms of maximizing enzyme yield, with the productivity improving at every stage to a fourfold output of enzyme (591.11 ±7.97 IU/mL) compared to the native strain (135±3.51 IU/mL).
Asunto(s)
Adaptación Biológica , Aeromonas veronii/enzimología , Aeromonas veronii/genética , Antineoplásicos/metabolismo , Glutaminasa/biosíntesis , Glutaminasa/genética , Mutación , Análisis de Varianza , Secuencia de Bases , Análisis Mutacional de ADNRESUMEN
Glutamine metabolism is emerging as one aspect of dysregulated metabolism of tumors. Triple-negative breast cancer (TNBC) cells are glutamine dependent, whereas luminal-type cells tend to be glutamine independent. Therefore, TNBC patients might benefit from therapies targeting glutamine metabolism. To investigate the clinical significance of glutamine metabolism, we examined expression and prognostic significance of glutaminase in tumor cells and tumor-infiltrating lymphocytes (TILs) in TNBC. We retrieved 658 surgically resected TNBCs and analyzed glutaminase expression in tumor cells and TILs by immunohistochemical staining. Glutaminase expression was observed in 237 cases (36.0%) in tumor cells and 104 cases (15.5%) in TILs. Although glutaminase expression in tumor cells was significantly associated with a low level of TILs (p = 0.018), glutaminase expression in TILs was significantly higher in cases with a high level of TILs (p = 0.031). Glutaminase expression in tumor cells was significantly associated with poor disease-free survival in patients with lymph node metastasis and high levels of TILs (p = 0.020). In addition, it was an independent poor prognostic factor (hazard ratio = 10.643, 95% confidence interval = 1.999-56.668; p = 0.006). Glutaminase expression in tumor cells was observed in a subset of TNBC patients. It was significantly associated with a low level of TILs and poor disease-free survival in TNBCs presenting with lymph node metastasis and high levels of TILs.
Asunto(s)
Biomarcadores de Tumor/análisis , Glutaminasa/biosíntesis , Linfocitos Infiltrantes de Tumor/patología , Neoplasias de la Mama Triple Negativas/patología , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Glutaminasa/análisis , Humanos , Inmunohistoquímica , Metástasis Linfática/patología , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Análisis de Matrices Tisulares , Neoplasias de la Mama Triple Negativas/enzimología , Neoplasias de la Mama Triple Negativas/mortalidadRESUMEN
Among all fungal endophytes isolates derived from different ethno-medical plants, the hyper-yield L-asparaginase and L-glutaminase wild strains Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20 using rice straw under solid-state fermentation (SSF) were selected. The selected strains were used as parents for the intergeneric protoplast fusion program to construct recombinant strain for prompt improvement production of these enzymes in one recombinant strain. Among 21 fusants obtained, the recombinant strain AYA 20-1, with 2.11-fold and 2.58-fold increase in L-asparaginase and L-glutaminase activities more than the parental isolates Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20, respectively, was achieved using rice straw under SSF. Both therapeutic enzymes L-asparaginase and L-glutaminase were purified and characterized from the culture supernatant of the recombinant AYA 20-1 strain with molecular weights of 50.6 and 83.2 kDa, respectively. Both enzymes were not metalloenzymes. Whereas thiol group blocking reagents such as p-chloromercurybenzoate and iodoacetamide totally inhibited L-asparaginase activity, which refer to sulfhydryl groups and cysteine residues involved in its catalytic activity, they have no effect toward L-glutaminase activity. Interestingly, potent anticancer, antioxidant, and antimicrobial activities were detected for both enzymes.