Fructose Diphosphate Aldolase Research Articles

Ascorbate−glutathione cycle involving in response of Bangia fuscopurpurea (Bangiales, Rhodophyta) to hyposalinity

Bangia fuscopurpurea is a widespread intertidal seaweed that is commercially cultured in China. This seaweed is frequently exposed to hyposalinity stress, but little is known about the adaptation mechanisms. Ascorbate−glutathione (AsA−GSH) cycle plays important roles in many organisms under a variety of abiotic stress, including hyposaline stress. In this study, we investigated the response of key metabolites and enzymes involved in the AsA−GSH cycle of B. fuscopurpurea under hyposalinity, with the addition of exogenous GSH and Lbuthionine-sulfoximine (BSO). The quantification of BfAPX gene expression was assessed across varied treatment regimens. And the putative interaction proteins of BfAPX were screened by yeast two hybrid system. It was found that under hyposalinity (15 and/or 0 psu), the content of reduced glutathione (GSH), total glutathione (GSH+ oxidized glutathione, GSSG) and cysteine, the ratio of GSH/GSSG and ascorbic acid (AsA)/ dehydroascorbic acid (DHA), and the activity of ascorbic acid peroxidase (APX) and monodehydroascorbate reductase (MDHAR) was significantly up-regulated. The hyposality-promoted GSH/GSSG was weakened while the glutathione reductase (GR) activity was promoted by adding exogenous GSH and BSO. The hyposality-promoted AsA/DHA ratio was strengthened by exogenous GSH but weakened by BSO. The dehydroascorbate reductase (DHAR) activity had no significant changes either with or without exogenous GSH under all salinities, while DHAR activity together with DHA content was enhanced by BSO. The expression of APX gene markedly increased under hyposalinity+BSO treatment. Putative interacting proteins of APX, including glutamate dehydrogenase 1a and fructose diphosphate aldolase, were identified through screening. The results indicated that the AsA−GSH cycle was involved in response of B. fuscopurpurea to hyposalinity by means of increasing GSH/GSSG ratio (through promoting GSH biosynthesis pathway and GSH regeneration from GSSG by GR catalyzation) and AsA/DHA ratio (promoting AsA regeneration through MDHAR). These findings would contribute to improve the aquaculture of this promising economic species and unveil how intertidal seaweeds address the global climate challenges.

Transcriptomics combined with metabolomics unveiled the key genes and metabolites of mycelium growth in Morchella importuna.

Morels (Morchella) are one of the most popular edible fungi in the world, especially known for their rich nutrition and delicious taste. Earlier research indicates that the production of fruiting bodies can be affected by the growth of mycelium. To investigate the molecular mechanisms underlying mycelium growth in Morchella importuna, we performed transcriptome analysis and metabolomics analysis of three growth stages of the hypha of M. importuna. As a result, 24 differentially expressed genes, such as transketolase (tktA), glucose-6-phosphate dehydrogenase (G6PDH), fructose-diphosphate aldolase (Fba), and ribose-5-phosphate isomerase (rpiA), as well as 15 differentially accumulated metabolites, including succinate and oxaloacetate, were identified and considered as the key genes and metabolites to mycelium growth in M. importuna. In addition, guanosine 3',5'-cyclic monophosphate (cGMP), guanosine-5'-monophosphate (GMP), and several small peptides were found to differentially accumulate in different growth stages. Furthermore, five pathways, namely, starch and sucrose metabolism, pentose and glucuronate interconversions, fructose and mannose metabolism, tyrosine metabolism, and purine nucleotides, enriched by most DEGs, existed in the three compared groups and were also recognized as important pathways for the development of mycelium in morels. The comprehensive transcriptomics and metabolomics data generated in our study provided valuable information for understanding the mycelium growth of M. importuna, and these data also unveiled the key genes, metabolites, and pathways involved in mycelium growth. This research provides a great theoretical basis for the stable production and breeding of morels.

The Activity and Gene Expression of Enzymes in Mycelia of Pleurotus Eryngii under Cadmium Stress

Cadmium (Cd) is a highly toxic pollutant and a nonessential element for plant growth. Here, we investigated the levels of malondialdehyde (MDA), H2O2, sugars, and the activity and gene expression of antioxidant enzymes and sugar metabolism-related enzymes in the mycelia of Pleurotus eryngii grown in the presence of 0, 0.5, 1, 1.5, 2.0, and 4.0 mg·L−1 Cd. Raising Cd concentration resulted in increases, followed by decreases in the levels of malondialdehyde (MDA) and H2O2 in the mycelia. The maximum concentrations of MDA and H2O2 reached 318.61 and 7411.40 μmol·L−1, respectively, at a Cd concentration of 1 mg·L−1. Antioxidative enzymes (superoxide dismutase (SOD), catalase, glutathione peroxidase (GPX), and ascorbate peroxidase (APX)) activities peaked at 1 mg·L−1 Cd. Furthermore, Pleurotus eryngii produced trehalose, glucose, fructose, and maltose in the fermentation broth in response to Cd stress. The levels of trehalose, arabinose, and fructose in the fermentation broth decreased continuously. The levels of glucose increased continuously, whereas those of maltose first increased and then decreased. Gene expression level of chitin synthase, glucose-1-phosphate uridyl transferase peaked significantly at 2 mg·L−1 of Cd, while that of trehalase 2 is 0.5 mg·L−1, and those for fructose-diphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, reached the maximum at 4 mg·L−1.

SRNA23, a novel small RNA, regulates to the pathogenesis of Streptococcus suis serotype 2

ABSTRACT Streptococcus suis serotype 2 (S. suis 2) is an important ubiquitous zoonotic pathogen. To date, regulatory factors and their implication in S. suis pathogenesis are not fully understood. Small non-coding RNAs (sRNAs) have been proven to function as important regulatory factors in bacterial pathogenesis and stress adaptation. Here, we identified a differentially downregulated S. suis 05ZYH33 sRNA after iron starvation by RNA-seq, which we named sRNA23. The presence of sRNA23 was further confirmed by RACE and Northern blot. Expression of sRNA23 was significantly altered under different environmental stresses such as nutritional starvation, osmotic pressure, oxidative stress, and lysozymal exposure. A sRNA23-deleted mutant exhibited relatively shorter streptococcal chains and weakened biofilm-forming ability. The mutation also resulted in decreased adherence of the S. suis 05ZYH33 to human laryngeal epidermoid carcinoma (HEp-2) cells, increased sensitivity to phagocytosis by RAW264.7 macrophages, and significantly reduced hemolytic activity. Furthermore, we observed that a sRNA23-deleted mutant had a low survival rate in pig whole blood and attenuated virulence in a mouse model. Moreover, based on RNA pull-down and electrophoretic mobility shift assay, we found that sRNA23 can directly bind to two proteins involved in adhesion and biofilm formation, namely, moonlighting protein FBA (fructose diphosphate aldolase) and rplB (50S ribosomal protein L2), respectively. Collectively, sRNA23 enhances S. suis 2 pathogenicity and the binding between sRNA23 and FBA/rplB might play an essential role in the adherence and biofilm-forming ability of S. suis 2. Abbreviation sRNA: small noncoding RNA; FBA: fructose diphosphate aldolase; rplB: 50S ribosomal protein L2; RACE: rapid amplification of cDNA ends; EMSA: electrophoretic mobility shift assay; THB: Todd-Hewitt broth; FBS: fetal bovine serum; BIP: 2,2ʹ-Bipyridine

Integration of proteome and transcriptome data reveals the mechanism involved in controlling of Fusarium graminearum by Saccharomyces cerevisiae.

It has been reported that antagonistic microorganisms could effectively control the infection of Fusarium graminearum. However, there is limited information on the control of F. graminearum by Saccharomyces cerevisiae, while the possible control mechanisms involved through proteomic and transcriptomic techniques have also not been reported. The results of this study showed that S. cerevisiae Y-912 could significantly inhibit the growth of F. graminearum Fg1, and the spore germination rate and germ tube length of F. graminearum Fg1 were also significantly inhibited by S. cerevisiae Y-912. Proteomic analysis revealed that differentially expressed proteins which were made of some basic proteins and enzymes related to basal metabolism, such as glyceraldehyde-3-phosphate dehydrogenase (GAPDH), phosphoglycerate mutase (PGAM), enolase (ENO), fructose diphosphate aldolase (FBA) and so on, were all down-regulated. The transcriptomics of F. graminearum control by S. cerevisiae was also analyzed. The control mechanism of S. cerevisiae Y-912 on F. graminearum Fg1 was a very complex material and energy metabolic process in which the related proteins and genes involved in the glycolytic pathway, tricarboxylic acid (TCA) cycle and amino acid metabolism were all down-regulated. © 2019 Society of Chemical Industry.

10.1007/s11171-008-2002-2

According to the previously reported data, the superntant of the primary culture of human erythrocytes contains 33 hemoglobin fragments. An analysis of the supernatant of a 20% (v/v) suspension of human erythrocytes allowed us to identify additionally four peptides whose precursors are cytoplasmic β-actin (two fragments), fructose diphosphate aldolase B, and an unknown protein, and amino acids tyrosine and tryptophan. The composition and the content of the components of the supernatant did not depend on the age and blood group of donors. The dynamics of accumulation in the supernatant (20–80 min of incubation) of 14 hemoglobin fragments with the most reliably reproducible contents was obtained. The content of six peptides increased more than twofold between 20 and 40 min of incubation; the maximum increase in concentration was observed between 40 and 80 min (140%). The level of peptides that had the maximum concentration at the end of incubation was about 1000 pmol/ml of sedimented erythrocytes. The biological effects of the peptides identified in the supernatant of erythrocytes involve the stimulation of proliferation and hemopoiesis, suppression of proliferation, a bactericide effect, etc. These effects indicate the physiological importance of the peptide release by erythrocytes.

Fragments of functional proteins in a primary culture of human erythrocytes

According to previously reported data, the supernatant of a primary culture of human erythrocytes contains 33 hemoglobin fragments. An analysis of the supernatant of a 20% (v/v) suspension of human erythrocytes allowed us to identify additionally four peptides whose precursors are cytoplasmic beta-actin (two fragments), fructose diphosphate aldolase B, and an unknown protein, as well as the amino acids tyrosine and tryptophan. The composition and the content of the components of the supernatant did not depend on the age or blood group of donors. The dynamics of accumulation in the supernatant (20-80 min of incubation) of the 14 hemoglobin fragments with the most reliably reproducible contents was obtained. The content of six peptides increased more than twofold between 20 and 40 min of incubation: the maximum increase in concentration was observed between 40 and 80 min (140%). The level of peptides that had the maximum concentration at the end of incubation was about 1000 pmol/ml of sedimented erythrocytes. The biological effects of the peptides identified in the supernatant of erythrocytes involve the stimulation of proliferation and hemopoiesis, suppression of proliferation, a bactericide effect, etc. These effects indicate the physiological importance of peptide release by erythrocytes. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2008, vol. 34, no. 2; see also http://www.maik.ru.

Some properties of two aldolases in extracts ofAspergillus oryzae

Fructose 1,6-diphosphate (FDP) aldolase and 2-keto-3-deoxy-D-gluconate (KDG) aldolase the two key enzymes of Embden-Meyerhof-Parnas (EMP) and the nonphosphorolytic Entner-Doudoroff (ED) pathways respectively, were identified in cell-free extracts of four Aspergillus oryzae strains grown on D-glucose as sole source of carbon. A. oryzae NRRL 3435 gave the highest enzymatic activity for the two enzymes and selected for further studies. Studies on the properties of the two key enzymes indicated that the optimum conditions for the activities of FDP aldolase and KDG aldolases occurred at pH 8.5, 45 degrees C and pH 8.0, 55 degrees C, respectively. Tris-acetate buffer and phosphate buffer showed the highest enzymatic activity for these two enzymes respectively. KDG aldolase was stable at 55 degrees C for 60 minutes however FDP aldolase was found to be less stable above 45 degrees C. On the other hand the two aldolases showed a high degree of stability towards frequent freezing and thawing. Dialysis of the extracts caused a decrease in the enzymatic activity of KDG aldolase, and an increase in FDP aldolase activity. The addition of ethylene diamine tetraacetate to the crude extracts caused an inhibition of KDG aldolase, whileas FDP aldolase was not affected. Addition of MnCl(2), CoSO(4), MgCl(2) and ZnSO(4) to the dialyzed extracts increased the activity of KDG aldolase by 67%, 54%, 61% and 37%, respectively. On the other hand the addition of some metal salts caused an inhibition of FDP aldolase. The results obtained indicate the absence of evidence for the involvement of sulfhydryl groups in the catalytic sites of the two aldolases.

Comparative study of the protein composition of three strains of Streptococcus thermophilus grown either in M17 medium or in milk

Streptococcus thermophilus is a lactic acid bacterium widely used for manufacturing milk products. The protein composition of three strains of S. thermophilus grown in either M17 me- dium or milk was investigated. These conditions were chosen on the basis of the observed technologi- cal differences between these strains. Protein extracts prepared from cells harvested at the same pH (5.2 ± 0.1), were analyzed by two-dimensional gel electrophoresis. Gel comparison revealed qualita- tive and quantitative differences between the two growth media and between the strains. Some pro- teins with quantitative variation were partially identified. The most significant medium-related differences concerned the number of spots detected and the heat shock protein (GroEL, HSP70) levels which were higher in milk than in M17. On the contrary, the levels of enzymes (proton translocating ATPase, pyruvate kinase, tributyrin esterase, phospho-glycerate kinase, glyceraldehyde-3-phosphate dehydrogenase, fructose diphosphate aldolase, superoxide dismutase) and of a putative penicillin binding protein were lower in milk than in M17. Strain-related differences were accentuated in milk for heat shock proteins, tributryrine esterase and dinitrogenase reductase. Streptococcus thermophilus / milk / proteome / 2D-PAGE electrophoresis

Synthesis and evaluation of six-membered GDP-iminocyclitol

Fructose-diphosphate aldolase was employed in the chemoenzymatic synthesis of six-membered GDP-iminocyclitols. These compounds were evaluated for activity against α-1,3-fucosyltransferases and found to be potent inhibitors.

Fermentation of pectin and glucose, and activity of pectin-degrading enzymes in the rumen bacterium Lachnospira multiparus.

Lachnospira multiparus belongs to the main rumen pectinolytic bacteria. Its carbohydrate metabolism was studied in growth experiments on laboratory fermenters, and using assays of activities of enzymes involved in pectin fermentation. The type strain of this species and two substrates were used. Lachnospira multiparus ATCC 19207 grew on pectin and glucose at a similar rate and had no preference for one or the other substrate. Pectin-grown cultures, however, produced significantly more acetate and less formate, lactate, ethanol, hydrogen, cell dry matter and protein than corresponding cultures grown on glucose. Extracellular exopectate lyase (EC 4.2.2.9) was the principal enzyme degrading the pectin macromolecule. Cell extracts possessed 2-keto-3- deoxy-6-phosphogluconate aldolase (EC 4.1.2.14) and fructosediphosphate aldolase (EC 4.1.2.13) activity. The former enzyme catalyses the final reaction in the Entner-Doudoroff pathway; the latter is the key enzyme of glycolysis and the pentose phosphate pathway. These results are consistent with the assumption that acidic products of pectin degradation are catabolized via a modified Entner-Doudoroff pathway. Phosphogluconate was not metabolized by cell extracts of the strain studied. This suggests that the conventional Entner-Doudoroff pathway of glucose utilization does not operate in this bacterium, presumably because of the lack of 6-phosphogluconate dehydrase (EC 4.2.1.12) activity.

Chemical-Enzymatic Synthesis of Iminocyclitol Phosphonic Acids

Fuculose 1-phosphate and fructose-diphosphate aldolases were employed in the chemoenzymatic synthesis of the iminocyclitols 1 and 2 possessing a phosphonic acid moiety. These compounds are useful as core synthons for the development of specific glycosyltransferase inhibitors.

Metabolism of pectin in rumen bacteria Butyrivibrio fibrisolvens and Prevotella ruminicola

Cultures of Butyrivibrio fibrisolvens 787 and Prevotella ruminicola AR29 grown on pectin produced significantly more acetate and less butyrate, lactate, succinate and hydrogen than corresponding cultures grown on l-arabinose and d-glucose. In both bacteria, fermentation of pectin and arabinose yielded less lactate than fermentation of glucose. Pectin-grown cells of these strains possessed activity of 2-keto-3-deoxy-6-phosphogluconate aldolase (EC 4·1.2·14), an enzyme catalysing the pyruvate formation in the Entner–Doudoroff pathway. The activity of fructosediphosphate aldolase (EC 4·1.2·13) was found both in cells cultivated on glucose and on pectin. The phosphoketolase activity (EC 4·1.2·9) could not be detected in rumen bacterial strains studied.

Use of FDP and F1P aldolase to detect tumorous and nontumorous tissue damage by ethanol injection of hepatocellular carcinoma.

Changes in serum levels of tumor-specific fructose 1,6-diphosphate (FDP) aldolase and nontumor-specific fructose 1-phosphate (F1P) aldolase activities were analyzed in patients with hepatocellular carcinoma (HCC) to detect the damage of tumorous and nontumorous hepatic cells after percutaneous ethanol injection (PEI). Initial PEI was performed in 20 patients containing 22 HCC nodules with a diameter of < or = 4 cm. Changes in serum hepatic enzyme activities were measured before and after repeated PEI. FDP and F1P aldolase levels were measured by substrate-specific enzymatic methods. Pre- and posttreatment alpha-fetoprotein (AFP) levels were determined by radioimmunoassay. The consequent changes in the total nontumorous liver volumes after PEI were also analyzed by follow-up CT scans. Serum levels of FDP aldolase released by ethanol injection were progressively increased (P < 0.0001) until the third PEI and thereafter decreased. In contrast, serum levels of F1P aldolase were continuously elevated even after the third PEI (P < 0.0001). Serum levels of transaminases were also elevated after repeated PEI (P < 0.0001). The FDP/FIP aldolase ratio decreased significantly with increased volume (>20 ml) of injected ethanol (P = 0.01) caused by nontumorous liver damage. The elevation of FDP aldolase was markedly associated with a decrease in serum levels of AFP (P < 0.001), indicating adequate tumor necrosis. The progression of the total nontumor liver atrophy depended on the volume of injected ethanol and correlated significantly with F1P aldolase levels after PEI (P < 0.01) but not with FDP aldolase. These results demonstrated that caution is needed to avoid nontumorous liver damage caused by the large volume of ethanol injection in treating HCC. Measurement of FDP and F1P aldolase activities in serum after PEI is clinically useful to detect the degree of tumorous and nontumorous tissue damage by ethanol.

Use of fructose 1,6-diphosphate aldolase to detect tumour necrosis after transcatheter arterial embolization of hepatocellular carcinoma.

Transcatheter arterial embolization (TAE) is a popular and well-established devascularization treatment modality for hepatocellular carcinoma (HCC). The persistent retention of lipiodol on follow-up computed tomography (CT) scan and time-dependent decrease in size of the lipiodol-stained area of tumour after TAE does not reveal the biological death of tumour cells. Moreover, it is difficult to clinically evaluate the effective necrosis of tumour cells by TAE in cases of HCC that do not produce alpha-fetoprotein (AFP). We therefore studied the release of a relatively tumour-specific protein by the necrotic hepatoma cells to evaluate the effectiveness of TAE. Transcatheter arterial embolization was performed in 17 patients with the imaging diagnosis of HCC; either superselective (n = 6) or non-superselective (n = 11) techniques were used. We measured serum levels of relatively tumour-specific fructose 1,6-diphosphate (FDP) aldolase and non-tumour-specific fructose 1-phosphate (F1P) aldolase by substrate-specific enzymatic methods. Enzyme activities were performed before and after TAE. The time-dependent decrease in size of the lipiodol-stained areas was studied on follow-up CT scans after TAE. Pre- and post-treatment serum AFP levels were determined by radio-immunoassay. The six cases of superselective TAE underwent marked tumour regression by CT compared with the 11 cases of non-superselective TAE. Fructase 1,6-diphosphate aldolase output correlated well with post-necrotic tumour regression after TAE (r = 0.87, P= 0.001). The elevation of serum FDP aldolase was also significantly associated with a decrease in serum AFP (r = 0.72, P < 0.01). In contrast, serum F1P aldolase output was inversely correlated with either tumour regression or serum AFP concentrations after TAE. The serum levels of the tumour-specific enzyme FDP aldolase correlated significantly with effective tumour necrosis and consequent tumour regression after TAE. We suggest that measurement of FDP aldolase activity in serum after TAE can be used clinically to detect the degree of tumour necrosis by TAE.

Cross-linked enzyme crystals of fructose diphosphate aldolase: Development as a biocatalyst for synthesis

Cross-linked enzyme crystals of fructose diphosphate aldolase: Development as a biocatalyst for synthesis

Cross-linked enzyme crystals of fructose diphosphate aldolase: Development as a biocatalyst for synthesis

Crystals of rabbit muscle aldolase were grown from 45% saturated ammonium sulfate solutions and cross-linked with glutaraldehyde to produce a biocatalyst that has stability for months, can be reisolated and reused, and has excellent solvent stability. This catalyst showed excellent reactivity with non-natural substrates.

Evaluation of nontumorous tissue damage by transcatheter arterial embolization for hepatocellular carcinoma.

The serial changes in serum hepatic enzyme activities by transcatheter arterial embolization (TAE) were analyzed in 17 patients with hepatocellular carcinoma to estimate the contribution to the value by the damage of tumor or nontumorous hepatic cells. The serum levels of relatively tumor-specific fructose 1,6-diphosphate (FDP) aldolase were elevated after TAE in the cases of both superselective and nonsuperselective TAE that were performed from the segmental and the nonsegmental hepatic artery, respectively, but we found the marked elevation of FDP aldolase in the cases of the superselective TAE. In contrast, the non-tumor-specific fructose 1-phosphate (F1P) aldolase was markedly elevated only in the cases of nonsuperselective TAE. The total amount of FDP aldolase released by TAE correlated significantly with the integrated tumor tissue volume (P less than 0.005), whereas the total amount of F1P aldolase output correlated significantly with the integrated nontumorous tissue volume (P less than 0.005) as defined by lipiodol accumulation on computerized tomography scan. The consequent changes in the total nontumorous liver volumes after TAE were also analyzed by the follow-up computerized tomography scan. The nonsuperselective TAE caused the significant total nontumorous liver atrophy when compared with the superselective TAE. The progression of the total nontumorous liver atrophy correlated significantly with F1P aldolase output by TAE (P less than 0.001) but not with FDP aldolase output. These results suggest that the outputs of FDP and F1P aldolase are useful to estimate the degree of the tumorous and nontumorous tissue damage by TAE, respectively, and F1P aldolase output can be used to predict the progression of liver atrophy caused by TAE.

Inactivation of mammalian fructose diphosphate aldolases by COOH terminus autophosphorylation

Rabbit skeletal muscle and liver fructose 1,6-diphosphate aldolases autophosphorylate in the presence of inorganic phosphate at physiological and alkaline pH. ATP as well as nonhydrolyzable ATP analogues inhibits autophosphorylation. Autophosphorylation of aldolases abolishes catalytic activity, which is restored upon treatment with alkaline phosphatase. Limited proteolysis of aldolase preferentially hydrolyzes the COOH terminus and liberates a phosphorylated peptide. Treatment of rabbit aldolases with carboxypeptidase, which liberates the COOH terminal residue Tyr 363, although modifying catalytic activity does not affect autophosphorylation. Amino acid analyses are consistent with results of autophosphorylation of the COOH terminus showing residue His 361 in muscle aldolase and Tyr 361 in liver aldolase. Phosphate lability in acid pH by phosphorylated muscle aldolase but not by phosphorylated liver aldolase corroborates the amino acid assignment. Autophosphorylation of the aldolases in the crystalline state is consistent with an intramolecular mechanism. The pH dependence of autophosphorylation being dependent on the enzyme's physical state (soluble or crystalline) is not inconsistent with crystallization stabilizing a conformer having different amino acid p k a values and/or reactivities than those of the soluble State.

Growth and metabolism in cotton and tobacco callus cultures

Activities of key enzymes of glycolytic and pentose phosphate pathways and krebs cycle were less in tobacco callus than in cotton callus cultures grown under identical conditions. The initial period of growth was characterized by high activities of invertase, acid phosphatase, hexokinase, fructose diphosphate aldolase, malate dehydrogenase, succinate dehydrogenase, glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase; the activities of these enzymes declined during the remainder period of growth.