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PubMed1989

Comparative ultrastructure of maturing toad (Bufo ictericus) and rabbit (Oryctolagus cuniculus) erythroid cells with regard to hemoglobin biosynthesis.

1. Toad and rabbit maturing erythroid cells were comparatively analysed with regard to their ultrastructural modifications involved in hemoglobin (Hb) biosynthesis. 2. The mitochondrial inner membrane differentiates to a lamellated body that, successively, gives rise to prehemosomal vesicles, prohemosomes, and to hemoglobinized organelles called hemosomes. 3. The prehemosomal vesicle involves ferruginous inclusions, taken as iron sources for heme biosynthesis, as well as the polypeptide globin chains, assembling themselves in the course of volume reduction. 4. From the prohemosomal stage onwards, where possibly heme biosynthesis occurs, hemosomes are formed; these organelles are presumably sites where the final Hb biosynthesis could take place. 5. All development stages leading to hemosome formation are similar in toad and rabbit erythroid cells, except that, in the toad, the structural prohemosome characteristics persist in hemosomes. 6. Through toad erythroid cell fractionation and electrophoresis of the organelle lysate supernatant, a wide and a weak cytoplasmic Hb bands were obtained; the latter coincides with the intraorganellar Hb band.

Animals↗

PubMed1991

Evidence for regulation of juvenile hormone biosynthesis operating before mevalonate in locust corpora allata.

Exogenous mevalonate poorly stimulated juvenile hormone III (JH-3) biosynthesis by corpora allata from Locusta migratoria. However, mevalonolactone strongly stimulated glands from different physiological states and fully restored JH synthesis in mevinolin-treated glands. Asymmetry in spontaneous rate of JH release was abolished by exogenous mevalonolactone. After transection of nervus corporis allati 1 (NCA-1), the rate of mevalonolactone-stimulated JH synthesis was maintained at the preoperative levels although the spontaneous rate of JH biosynthesis decreased rapidly. These results suggest that the spontaneous asymmetry of JH biosynthesis and the low rate of JH biosynthesis by denervated corpora allata both result from non-stimulation or inhibition acting on the JH pathway before the utilisation of mevalonate.

Animals↗

PubMed1993

Characterization of progesterone biosynthesis in a transformed granulosa cell line.

The study of regulation of steroidogenesis in primary cultures of rat granulosa cells is difficult because the cells do not undergo more than one cell doubling in culture. Furthermore, there is size and steroidogenic heterogeneity in granulosa cells and it is difficult to obtain pure, functionally defined populations. Hence, it is advantageous to develop a homogeneous population of granulosa cells. In this report we describe the characterization of one such cell line (Rao-gcl-29) developed from diethylstilbestrol treated immature rat granulosa cells by transformation with SV40 T antigen. In this cell line cyclic AMP analogs induce high levels of progesterone biosynthesis, though there was no effect on estradiol biosynthesis. Also, FSH and hCG have no effect on progesterone biosynthesis. In the presence of FBS medium (20% fetal bovine serum in DMEM/F-12) and enriched medium (10% fetal bovine serum, 10% horse serum and 2% UltraSer G in DMEM/F-12 medium), 1 mM cAMP analogs induce high levels of progesterone biosynthesis up to 96 h. Ultrastructural features of the cell line resemble those of primary granulosa cells, in addition to forming gap junctions. Cyclic AMP analogs also induced cytochrome P450scc mRNA in this cell line by 48 h, and this effect is apparent by 24 h. Thus, this cell line could be useful in understanding the molecular mechanisms of regulation of cytochrome P450scc gene regulation.

Animals↗

PubMed1994

Inhibition of ecdysone biosynthesis in flies by a hexapeptide isolated from vitellogenic ovaries.

The only identified insect peptides known to be involved in controlling the biosynthesis of ecdysone, the steroid moulting hormone of arthropods, are the prothoracicotropic hormones (PTTH). These neuropeptides stimulate ecdysone biosynthesis. Recently, a hexapeptide (NPTNLH) with folliculostatic and trypsin modulating activity was isolated from vitellogenic ovaries of the fleshfly Neobellieria bullata. Here we report that the hexapeptide, when tested in vitro on the isolated ring gland of flies, inhibited ecdysone biosynthesis immediately and completely (EC50 = 5 nM). The hexapeptide is the first known factor with 'prothoracicostatic activity' and may form part of the endocrine system that controls ecdysone biosynthesis in vivo.

Animals↗

PubMed1992

The isolation and characterization of antibiotic biosynthesis genes.

Antibiotic biosynthesis pathways are found in a broad range of Gram positive prokaryotes, a smaller range of Gram negative prokaryotes and a limited range of eukaryotes. A variety of techniques can be used to identify the genes involved in the biosynthesis of these compounds ranging from genetic complementation and interspecific gene transfer to polymerase chain reaction amplification and transposon mutagenesis. The dissection of these cloned pathways and the understanding of their structure and regulation has led to insights into the structure and function of antibiotic biosynthesis genes. With new knowledge of the structural similarities and relationships between related antibiotic biosynthesis pathways, the possibility of directed manipulation of specific genes to allow synthesis of novel antibiotics is now possible.

Journal Article↗

PubMedDate not supplied

Role of various carbon and nitrogen sources in the regulation of enzymes of pyrimidine biosynthesis in Mycobacterium smegmatis TMC 1546.

Pyrimidine biosynthesis and its regulation in the presence of different carbon and nitrogen sources in the growth medium of Mycobacterium smegmatis were studied. M. smegmatis TMC 1546 cells grown in shake culture were found to have marginally higher pyrimidine enzyme biosynthesis activities than cells grown in static culture. The activity was highest at the mid-log phase of growth during both surface and shake cultures, suggesting that the cells were metabolically most active at this stage of growth. Replacement of glycerol by glucose and fructose slightly increased the activities of carbamyl phosphate synthetase and aspartate transcarbamylase. The enzyme activities involved in pyrimidine biosynthesis decreased when citrate was replaced by succinate, fumarate, pyruvate or acetate in the growth medium. The activities of the enzymes in pyrimidine biosynthesis were found to decrease when asparagine as a nitrogen source in the medium was replaced by glutamate, glutamine or ammonium chloride. The presence of ornithine in place of asparagine in the growth medium increased these enzyme activities, while the presence of arginine instead of asparagine in the growth medium decreased these enzyme activities, though the differences in activity were small. The activity of aspartate transcarbamylase in vitro was inhibited by arginine. In the case of cells grown in the presence of ornithine, the activity of aspartate transcarbamylase was induced by ornithine, but inhibited by arginine.

Amino Acids↗

PubMedDate not supplied

Regulation of nisin biosynthesis by continuous cultures and by resting cells of Lactococcus lactis subsp. lactis.

Nisin production by Lactococcus lactis subsp. lactis has been investigated using lactose as carbon source. Whether or not continuous cultures were lactose-limited, maximum nisin titre was observed at an intermediate mu value with a sharp peak of activity between 0.2 and 0.3/h. The maximum specific growth rate obtained in the medium used was 0.6/h and the maximum titre of nisin at mu = 0.25/h (160 AU/ml) was about nine-fold higher as compared with activity obtained at a dilution rate of 0.05/h or 0.4/h. With a constant dilution rate of 0.25/h and varying initial lactose concentrations from 3 to 40 g/l, there is an increase in nisin biosynthesis with increasing lactose concentration correlated with higher rates of sugar consumption. A Ymax value of 0.2 g bacterial dry weight and a maintenance coefficient of 124 mg lactose/g bacterial dry weight/h were determined. Lactose consumption increased from 1 to 3.28 g of lactose/g (dry wt) of cell mass/h and the nisin titre from 12.5 to 164.2 AU/ml. At higher values, nisin production declined. This implies that biosynthesis of nisin is regulated by a system of repression and derepression. Addition of lanthionine and beta-methyllanthionine precursors to the medium decreased the nisin titre when either threonine, threonine-cysteine, or cysteine-serine-threonine was added at the optimal dilution rate of 0.25/h; however, simultaneous addition of serine and cysteine elicited a slight increase in nisin activity. Studies with resting cells confirm that the biosynthesis of nisin is tightly regulated, since the production rate can be 5.6-fold higher than in cells grown in continuous culture. In addition, cell-adhered nisin appears to play a role in the production of the enzyme: low levels of cell-adhered nisin elicited high production rates, whereas high levels were not associated with nisin biosynthesis. In addition to pH, magnesium sulphate and lactose concentrations, nitrogen sources were also able to interfere in cell-adherence nisin.

Culture Media↗

PubMed1988

Comparative effects on TXA2 biosynthesis of products extracted from Lippia multiflora Moldenke leaves.

The effects of the total phenolic extract (TPLi) from Lippia multiflora leaves and of its 2 main components i.e. Verbascoside (VLi) and Lil on TXA2 biosynthesis were studied. TXA2 biosynthesis was induced by incubation of arachidonic acid with horse platelet microsomes (HPM), TXB2, a stable metabolite of TXA2, was determined by using RIA. Under the experimental conditions adopted, Verbascoside did not significantly modify TXA2 biosynthesis. On the contrary, the total phenolic extract and Lil both inhibited TXA2 biosynthesis. Their action was dose-related, Lil being the more potent. The ID50 were 1.19 +/- 0.08 mg/ml and 10.64 +/- 0.64 mg/ml for Lil and total phenolic extract respectively. The study of regression curves representing the hypotensive action and the anti-thromboxane synthetase activity versus log(dose) of TPLi and Lil suggested that Lil would likely be responsible for the TPLi hypotensive action. Its antithromboxane synthetase activity could be considered as a major contributor to the mechanism of this effect.

Animals↗

PubMed1990

Cyclic AMP does not inhibit A23187-induced prostaglandin biosynthesis in cultured rabbit renal microvascular endothelial cells.

We have previously shown that cultured rabbit renal preglomerular microvascular endothelial cells have the ability to synthesize a number of common prostaglandins. In the present study we have examined whether endogenous cyclic AMP is involved in the regulation of PGI2 and PGE2 biosynthesis in these cultured cells. Isoproterenol and forskolin produced an increase in cyclic AMP accumulation in these cells but had no effect on PGI2 or PGE2 biosynthesis either in the presence or absence of A23187. Similar results were noted in the presence of 3-isobutyl-1-methylxanthine, a cyclic AMP-phosphodiesterase inhibitor. These studies suggested that endogenous cyclic AMP does not regulate the biosynthesis of PGI2 or PGE2 in cultured renal preglomerular microvascular endothelial cells either under basal or A23187-stimulated condition. They further suggested that the effect of 3-isobutyl-1-methylxanthine on prostaglandin biosynthesis in these cultured cells was not secondary to its effects on phosphodiesterase.

1-Methyl-3-isobutylxanthine↗

PubMed1991

Epidermal growth factor and the regulation of amnion prostaglandin biosynthesis.

The production of prostaglandins by amnion is a key factor in the mechanism of human parturition yet the regulation of prostaglandin biosynthesis in amnion is poorly understood. Hence, we have investigated the regulation of epidermal growth factor (EGF) stimulation of prostaglandin biosynthesis in human amnion cells. This stimulatory action is inhibited by cycloheximide or actinomycin D at high concentrations, but enhanced at much lower concentrations of these protein synthesis inhibitors. An amnion-produced prostaglandin inhibitor or immediate early gene action may explain these effects. Pretreatment with phorbol esters (inhibition of protein kinase C activity) reduces basal prostaglandin production and attenuates the stimulatory action of EGF on prostaglandin biosynthesis. Hence, amnion prostaglandin biosynthesis is dependent partly on protein kinase C activity.

Amnion↗

PubMed1996

Specific inhibition of the last steps of aldosterone biosynthesis by 18-vinylprogesterone in bovine adrenocortical cells.

18-Vinylprogesterone (18-VP), designed for mechanism-based specific inhibition of the last steps of the aldosterone biosynthesis, was used to characterize the mechanism of the 11 - and 18-hydroxylase activities of bovine cytochrome P450(11beta). In the present work, its action was studied by observations on a primary culture of bovine adrenocortical cells. First, we investigated the effects of 18-VP on the different enzymatic steps of the biosynthesis of cortisol and aldosterone. The production of cortisol, baseline or hormone-stimulated (ACTH or AII), was inhibited by 18-VP in a dose-dependent manner with a maximal inhibition at 5 microM. Supply of different exogenous substrates to support steroidogenesis revealed an inhibition of the last step of cortisol or corticosterone biosynthesis. We then used specific blockers to measure individual activities and conclude that 11beta-hydroxylation was the only enzymatic activity affected. Aldosterone, as well as 18-hydroxycorticosterone, was also measured following addition of corticosterone. The 18-hydroxylation of corticosterone was inhibited by 18-VP, with 50% inhibition occurring at 0.04 microM compared with the 50% inhibition value of 0.3 microM obtained for 11-hydroxylation. Surprisingly, 18-ethynyl-progesterone (18-EP), which has a structure very similar to 18-VP, only weakly inhibits 11beta-hydroxylation. The inhibition of aldosterone formation was also much lower with 18-EP than with 18-VP. These studies demonstrate that 18-VP inhibits only the later steps of aldosterone biosynthesis and more specifically 18- than 11-hydroxylation activity.

Adrenal Cortex↗

PubMed1996

Regulation of sterol 27-hydroxylase and an alternative pathway of bile acid biosynthesis in primary cultures of rat hepatocytes.

In man, hepatic mitochondrial sterol 27-hydroxylase and microsomal cholesterol 7alpha-hydroxylase initiate distinct pathways of bile acid biosynthesis from cholesterol, the "acidic" and "neutral" pathways, respectively. A similar acidic pathway in the rat has been hypothesized, but its quantitative importance and ability to be regulated at the level of sterol 27-hydroxylase are uncertain. In this study, we explored the molecular regulation of sterol 27-hydroxylase and the acidic pathway of bile acid biosynthesis in primary cultures of adult rat hepatocytes. mRNA and protein turnover rates were approximately 10-fold slower for sterol 27-hydroxylase than for cholesterol 7alpha-hydroxylase. Sterol 27-hydroxylase mRNA was not spontaneously expressed in culture. The sole requirement for preserving sterol 27-hydroxylase mRNA at the level of freshly isolated hepatocytes (0 h) after 72 h was the addition of dexamethasone (0.1 microM; > 7-fold induction). Sterol 27-hydroxylase mRNA, mass and specific activity were not affected by thyroxine (1.0 microM), dibutyryl-cAMP (5O microM), nor squalestatin 1 (15O nM-1.0 microM), an inhibitor of cholesterol biosynthesis. Taurocholate (50 microM), however, repressed sterol 27-hydroxylase mRNA levels by 55%. Sterol 27-hydroxylase specific activity in isolated mitochondria was increased > 10-fold by the addition of 2-hydroxypropyl-beta-cyclodextrin. Under culture conditions designed to maximally repress cholesterol 7alpha-hydroxylase and bile acid synthesis from the neutral pathway but maintain sterol 27-hydroxylase mRNA and activity near 0 h levels, bile acid synthesis from [14C]cholesterol remained relatively high and consisted of beta-muricholate, the product of chenodeoxycholate in the rat. We conclude that rat liver harbors a quantitatively important alternative pathway of bile acid biosynthesis and that its initiating enzyme, sterol 27-hydroxylase, may be slowly regulated by glucocorticoids and bile acids.

Animals↗

PubMed1992

UVA- and UVB-induced changes in collagen and fibronectin biosynthesis in the skin of hairless mice.

The modifications induced in hairless mouse skin by chronic UV irradiation were investigated. Skin explant cultures were used to study UVA- and UVB-induced changes occurring in interstitial collagen (type I and type III) and fibronectin biosynthesis. To study the long-term effects, albino hairless mice were irradiated with UVA radiation alone from two sources with different spectral qualities or with UVB. UVA and UVB radiation produced a significant increase in the ratio of type III to type I collagen (more than 100% for UVA-irradiated skin and about 60% for UVB-irradiated skin) accompanied by a significantly increased fibronectin biosynthesis (50% or more in all irradiated groups). Irradiation with either UVA or UVB alone had no significant effect on the total collagen synthesis and resulted in only a slight decrease in the total collagen content of the skin determined as hydroxyproline. This decrease was significant only in the case of the group irradiated with UVA (xenon) (decrease of 25%, expressed as micrograms of hydroxyproline per milligram wet weight). A significant decrease in collagen hydroxylation (expressed as radioactive hydroxyproline/radioactive hydroxyproline plus proline in neosynthesized collagen) was observed of about 50% in skin irradiated with UVA (xenon) but not in UVB-treated skin. Several of the above modifications (increased fibronectin biosynthesis, increased collagen type III to type I ratio) correspond to the modifications observed during the aging of non-irradiated hairless mice. Therefore it appears that UV irradiation accelerates the modifications of extracellular matrix biosynthesis observed during aging.

Amino Acids↗

PubMed2004

Tetrahydrobiopterin biosynthesis in white and brown adipose tissues is enhanced following intraperitoneal administration of bacterial lipopolysaccharide.

Tetrahydrobiopterin is an essential cofactor for nitric oxide synthase (NOS). This study was undertaken to examine the effects of intraperitoneally injected lipopolysaccharide on tetrahydrobiopterin biosynthesis in murine white and brown adipose tissues. Tetrahydrobiopterin content, catalytic activity and mRNA expression level of GTP cyclohydrolase I (GCH), rate-controlling enzyme in de novo biosynthesis of tetrahydrobiopterin, in both adipose tissues were up-regulated by 500-microg lipopolysaccharide at 6 h after the injection. On the contrary, treatment of 3T3-L1 adipocytes with lipopolysaccharide alone did not affect GCH mRNA expression level, whereas the combination of lipopolysaccharide, tumor necrosis factor (TNF)-alpha, and interferon gamma induced the increase in expression levels of GCH mRNA and CD14 mRNA. Collectively, our results showed that tetrahydrobiopterin biosynthesis can be augmented by increased GCH activity caused by a synergistic effect of lipopolysaccharide and cytokines in white and brown adipose tissues. These observations support the view that tetrahydrobiopterin biosynthesis in the adipose tissues is a target of inflammatory events triggered by peripheral LPS injection.

3T3-L1 Cells↗

PubMed2006

New insights into the regulation of cardiolipin biosynthesis in yeast: implications for Barth syndrome.

Recent studies have revealed an array of novel regulatory mechanisms involved in the biosynthesis and metabolism of the phospholipid cardiolipin (CL), the signature lipid of mitochondria. CL plays an important role in cellular and mitochondrial function due in part to its association with a large number of mitochondrial proteins, including many which are unable to function optimally in the absence of CL. New insights into the complexity of regulation of CL provide further evidence of its importance in mitochondrial and cellular function. The biosynthesis of CL in yeast occurs via three enzymatic steps localized in the mitochondrial inner membrane. Regulation of this process by general phospholipid cross-pathway control and factors affecting mitochondrial development has been previously established. In this review, novel regulatory mechanisms that control CL biosynthesis are discussed. A unique form of inositol-mediated regulation has been identified in the CL biosynthetic pathway, independent of the INO2-INO4-OPI1 regulatory circuit that controls general phospholipid biosynthesis. Inositol leads to decreased activity of phosphatidylglycerolphosphate (PGP) synthase, which catalyzes the committed step of CL synthesis. Reduced enzymatic activity does not result from alteration of expression of the structural gene, but is instead due to increased phosphorylation of the enzyme. This is the first demonstration of phosphorylation in response to inositol and may have significant implications in understanding the role of inositol in other cellular regulatory pathways. Additionally, synthesis of CL has been shown to be dependent on mitochondrial pH, coordinately controlled with synthesis of mitochondrial phosphatidylethanolamine (PE), and may be regulated by mitochondrial DNA absence sensitive factor (MIDAS). Further characterization of these regulatory mechanisms holds great potential for the identification of novel functions of CL in mitochondrial and cellular processes.

Acyltransferases↗

PubMed2003

Identification and characterization of a cDNA encoding a long-chain cis-isoprenyltranferase involved in dolichyl monophosphate biosynthesis in the ER of brain cells.

A long-chain cis-isoprenyltransferase (cis-IPTase) located in the endoplasmic reticulum (ER) catalyzes the chain elongation stage in the pathway for the de novo biosynthesis of dolichyl monophosphate (Dol-P) in eukaryotic cells. In Saccharomyces cerevisiae, the ER-associated cis-IPTase is encoded by the RER2 gene. Mutations in the RER2 gene result in defects in growth and protein N-glycosylation. In this study a cDNA isolated from human brain (Accession No. AK023164.1), which has substantial homology to cis-IPTases from bacteria, Arabidopsis, and S. cerevisiae, has been shown to: (1) complement the growth defect; (2) restore cis-IPTase activity; dolichol and Dol-P synthesis; and (3) restore normal N-glycosylation of carboxypeptidase Y (CPY) in the yeast rer2Delta mutant. Consistent with a role in Dol-P biosynthesis, overexpression of the human cis-isoprenyltransferase (hCIT) cDNA also suppresses the temperature-sensitive growth and CPY hypoglycosylation phenotypes in sec59-1 cells which are defective in Dol-P biosynthesis due to a temperature-sensitive mutation in dolichol kinase. Overexpression of hCIT in Chinese hamster ovary (CHO) cells results in a modest increase in cis-IPTase activity associated with microsomal fractions and the appearance of a new 38kDa polypeptide that co-localizes with calnexin in the ER, the site of Dol-P biosynthesis, even though no transmembrane domains are predicted by a hydropathy plot.

Alkyl and Aryl Transferases↗

PubMed2004

COX-2-mediated PGD2 synthesis regulates phosphatidylcholine biosynthesis in rat renal papillary tissue.

Phosphatidylcholine (PC) is the major membrane phospholipid in mammalian cells. Previous works from our laboratory demonstrated a close metabolic relationship between the maintenance of PC biosynthesis and the prostaglandins endogenously synthesized by cyclooxygenase (COX) in rat renal papilla. In the present work, we studied the COX isoform involved in papillary PC biosynthesis regulation. The incorporation of [methyl-3H]choline and [32P]orthophosphate to PC was determined in the absence and presence of SC-560 and NS-398, COX-1 and COX-2 specific inhibitors. PC synthesis was highly sensitive to COX-2 inhibition, while COX-1 inhibition only reduced PC synthesis at high SC-560 concentration. The analysis of choline-containing metabolites showed that COX-2 inhibition affected the formation of CDP-choline intermediary. The evaluation of PC biosynthetic enzymes revealed that microsomal, as well as nuclear, CTP:phosphocholine cytidylyltransferase (CCT), and nuclear-CDP-choline:1,2-diacylglycerol cholinephosphotransferase (CTP) activities were affected by COX-2 inhibition. The addition of exogenous prostaglandin D(2) (PGD(2)) restored nuclear-CCT and -CPT activities but not microsomal CCT. Papillary synthesis of PGD(2) was only detected in nuclear fraction where it was blocked by COX-2 inhibitor NS-398, but not by COX-1 inhibitor. All together, the present results demonstrated that COX-2-mediated PGD(2) synthesis is a PC biosynthesis regulator in rat renal papilla. Considering the importance of the maintenance of PC biosynthesis for the preservation of cell membrane homeostasis to ensure cell viability, and the extensive use of COX-2 inhibitors in therapeutics, the present results could have great pharmacological implications, and can constitute a biochemical explanation for the nephrotoxic effect of non-steroidal anti-inflammatory drugs.

Animals↗

PubMed2005

Starch biosynthesis: the primer nonreducing-end mechanism versus the nonprimer reducing-end two-site insertion mechanism.

Two mechanisms are recognized for polysaccharide chain elongation: (a) the nonreducing-end, primer-dependent mechanism and (b) the reducing-end, two-site insertion mechanism. We recently demonstrated the latter mechanism for starch biosynthesis by pulsing starch granules with ADP-[14C]Glc and chasing with ADPGlc for eight varieties of starch granules. Others have reported the addition of glucose from ADPGlc to the nonreducing ends of maltose, maltotriose, and maltopentaose and a branched maltopentasaccharide. It was concluded that starch chains are biosynthesized by the addition of glucose to the nonreducing ends of maltodextrin primers. In this study, we reinvestigated the maltodextrin reactions by reacting three kinds of starch granules from maize, wheat, and rice with ADP-[14C]Glc in the absence and presence of maltose (G2), maltotriose (G3), and maltodextrin (d.p.12) and found that they inhibited starch biosynthesis rather than stimulating it, as would be expected for primers. The major product in the presence of G2 was G3 with decreasing amounts of G4-G9 and the major products in the presence of G3 was G4 and G5, with decreasing amounts of G6-G9. It was concluded that maltodextrins are acceptors rather than primers. This was confirmed by pulsing the starch granules with ADP-[14C]Glc and chasing with G2, G3, and G6, which gave release of 14C-label from the pulsed granules in the absence of ADPGlc, further demonstrating that maltodextrins are acceptors that inhibit starch biosynthesis by releasing glucose from starch synthase, rather than acting as primers and stimulating biosynthesis.

Adenosine Diphosphate Glucose↗