Tryptophan plays an important role in yeast’s tolerance to isobutanol

Abstract Background Isobutanol is considered a potential biofuel, thanks to its high-energy content and octane value, limited water solubility, and compatibility with gasoline. As its biosynthesis pathway is known, a microorganism, such as Saccharomyces cerevisiae, that inherently produces isobutanol, can serve as a good engineering host. Isobutanol’s toxicity, however, is a major obstacle for bioproduction. This study is to understand how yeast tolerates isobutanol. Results A S. cerevisiae gene-deletion library with 5006 mutants was used to screen genes related to isobutanol tolerance. Image recognition was efficiently used for high-throughput screening via colony size on solid media. In enrichment analysis of the 161 isobutanol-sensitive clones identified, more genes than expected were mapped to tryptophan biosynthesis, ubiquitination, and the pentose phosphate pathway (PPP). Interestingly, adding exogenous tryptophan enabled both tryptophan biosynthesis and PPP mutant strains to overcome the stress. In transcriptomic analysis, cluster analysis of differentially expressed genes revealed the relationship between tryptophan and isobutanol stress through some specific cellular functions, such as biosynthesis and transportation of amino acids, PPP, tryptophan metabolism, nicotinate/nicotinamide metabolism (e.g., nicotinamide adenine dinucleotide biosynthesis), and fatty acid metabolism. Conclusions The importance of tryptophan in yeast’s tolerance to isobutanol was confirmed by the recovery of isobutanol tolerance in defective strains by adding exogenous tryptophan to the growth medium. Transcriptomic analysis showed that amino acid biosynthesis- and transportation-related genes in a tryptophan biosynthesis-defective host were up-regulated under conditions similar to nitrogen starvation. This may explain why ubiquitination was required for the protein turnover. PPP metabolites may serve as precursors and cofactors in tryptophan biosynthesis to enhance isobutanol tolerance. Furthermore, the tolerance mechanism may also be linked to tryptophan downstream metabolism, including the kynurenine pathway and nicotinamide adenine dinucleotide biosynthesis. Both pathways are responsible for cellular redox balance and anti-oxidative ability. Our study highlights the central role of tryptophan in yeast’s isobutanol tolerance and offers new clues for engineering a yeast host with strong isobutanol tolerance.

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Increased nicotinamide adenine dinucleotide content and synthesis in Plasmodium falciparum-infected human erythrocytes

Blood ◽

10.1182/blood.v75.8.1705.1705 ◽

1990 ◽

Vol 75 (8) ◽

pp. 1705-1710 ◽

Cited By ~ 25

Author(s):

CR Zerez ◽

EF Jr Roth ◽

S Schulman ◽

KR Tanaka

Keyword(s):

Plasmodium Falciparum ◽

Nicotinic Acid ◽

Nicotinamide Adenine Dinucleotide ◽

Biosynthetic Pathway ◽

Pentose Phosphate ◽

Nicotinamide Adenine ◽

Nicotinamide Phosphoribosyltransferase ◽

Nad Synthesis ◽

Infected Rbcs ◽

Nicotinic Acid Phosphoribosyltransferase

Abstract Plasmodium falciparum-infected red blood cells (RBCs) are characterized by increases in the activity of glycolytic enzymes. Because nicotinamide adenine dinucleotide (NAD) and NAD phosphate (NADP) are cofactors in the reactions of glycolysis and pentose phosphate shunt, we have examined NAD and NADP content in P. falciparum-infected RBCs. Although NADP content was not significantly altered, NAD content was increased approximately 10-fold in infected RBCs (66% parasitemia) compared with uninfected control RBCs. To determine the mechanism for the increase in NAD content, we examined the activity of several NAD biosynthetic enzymes. It is known that normal human RBCs make NAD exclusively from nicotinic acid and lack the capacity to make NAD from nicotinamide. We demonstrate that infected RBCs have readily detectable nicotinamide phosphoribosyltransferase (NPRT), the first enzyme in the NAD biosynthetic pathway that uses nicotinamide, and abundant nicotinamide deamidase, the enzyme that converts nicotinamide to nicotinic acid, thereby indicating that infected RBCs can make NAD from nicotinamide. In addition, infected RBCs have a threefold increase in nicotinic acid phosphoribosyltransferase (NAPRT), the first enzyme in the NAD biosynthetic pathway that uses nicotinic acid. Thus, the increase in NAD content in P falciparum-infected RBCs appears to be mediated by increases in NAD synthesis from both nicotinic acid and nicotinamide.

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Theoretical Analysis of the Built-in Metabolic Pathway Effect on the Metabolism of Erythrocyte-Bioreactors That Neutralize Ammonium

Metabolites ◽

10.3390/metabo11010036 ◽

2021 ◽

Vol 11 (1) ◽

pp. 36

Author(s):

Evgeniy Protasov ◽

Larisa Koleva ◽

Elizaveta Bovt ◽

Fazoil I. Ataullakhanov ◽

Elena Sinauridze

Keyword(s):

Steady State ◽

Glutamate Dehydrogenase ◽

Pentose Phosphate Pathway ◽

Nicotinamide Adenine Dinucleotide ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Pentose Phosphate ◽

Nicotinamide Adenine ◽

Limiting Factor ◽

Glutamate Dehydrogenase Activity ◽

Reduced Nicotinamide Adenine Dinucleotide

The limitations of the efficiency of ammonium-neutralizing erythrocyte-bioreactors based on glutamate dehydrogenase and alanine aminotransferase reactions were analyzed using a mathematical model. At low pyruvate concentrations in the external medium (below about 0.3 mM), the main limiting factor is the rate of pyruvate influx into the erythrocyte from the outside, and at higher concentrations, it is the disappearance of a steady state in glycolysis if the rate of ammonium processing is higher than the critical value (about 12 mM/h). This rate corresponds to different values of glutamate dehydrogenase activity at different concentrations of pyruvate in plasma. Oxidation of reduced nicotinamide adenine dinucleotide phosphate (NADPH) by glutamate dehydrogenase decreases the fraction of NADPH in the constant pool of nicotinamide adenine dinucleotide phosphates (NADP + NADPH). This, in turn, activates the pentose phosphate pathway, where NADP reduces to NADPH. Due to the increase in flux through the pentose phosphate pathway, stabilization of the ATP concentration becomes impossible; its value increases until almost the entire pool of adenylates transforms into the ATP form. As the pool of adenylates is constant, the ADP concentration decreases dramatically. This slows the pyruvate kinase reaction, leading to the disappearance of the steady state in glycolysis.

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The role of 6-phosphogluconate dehydrogenase in Rhizobium

Canadian Journal of Microbiology ◽

10.1139/m77-193 ◽

1977 ◽

Vol 23 (9) ◽

pp. 1293-1298 ◽

Cited By ~ 4

Author(s):

Kalemani Mulongoy ◽

Gerald H. Elkan

Keyword(s):

Enzyme Activity ◽

Nicotinamide Adenine Dinucleotide ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Pentose Phosphate ◽

Nicotinamide Adenine ◽

Phosphogluconate Dehydrogenase ◽

Ketonic Group ◽

Fast Growing Rhizobia

A nicotinamide adenine dinucleotide (NAD) linked 6-phosphogluconate (6-PG) dehydrogenase has been detected in Rhizobium. The enzyme activity is similar in both slow- and fast-growing rhizobia. The nicotinamide adenine dinucleotide phosphate (NADP) dependent 6-PG dehydrogenase was detected only in the fast growers and was more than twice as active as the NAD-linked enzyme. Partial characterization of the products of 6-PG oxidation in Rhizobium suggests that the NADP-linked enzyme is the decarboxylating enzyme of the pentose phosphate (PP) pathway (EC 1.1.1.44) whereas a phosphorylated six-carbon compound, containing ketonic group(s), is the product of the oxidation catalyzed by the NAD-linked enzyme.

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Increasing nicotinamide adenine dinucleotide phosphate hydrogen levels via pentose phosphate pathway promotes phyenylpropanoid metabolism of fresh-cut white mushroom (Agaricus bisporus) under high O2/CO2 storage

Scientia Horticulturae ◽

10.1016/j.scienta.2021.110873 ◽

2022 ◽

Vol 295 ◽

pp. 110873

Author(s):

Liang Wang ◽

Yanyin Guo ◽

Xiangyou Wang

Keyword(s):

Pentose Phosphate Pathway ◽

Nicotinamide Adenine Dinucleotide ◽

Agaricus Bisporus ◽

Co2 Storage ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Pentose Phosphate ◽

Nicotinamide Adenine ◽

High O2 ◽

Fresh Cut

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Development of a single-step fluorogenic sirtuin assay and its applications for high-throughput screening

Organic & Biomolecular Chemistry ◽

10.1039/d1ob02347k ◽

2022 ◽

Author(s):

Pan Wang ◽

Di Chen ◽

Jianxiong An ◽

Shu-xian Lin ◽

Ting Liu ◽

...

Keyword(s):

High Throughput ◽

Nicotinamide Adenine Dinucleotide ◽

Histone Deacetylases ◽

High Throughput Screening ◽

Single Step ◽

Nicotinamide Adenine

Sirtuins (SIRTs) are a class of nicotinamide adenine dinucleotide (NAD+)-dependent histone deacetylases. Since SIRTs have different subcellular locations and different preferences for deacylation activity, SIRTs are not only highly gaining...

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Reduced Nicotinamide Adenine Dinucleotide Phosphate, a Pentose Phosphate Pathway Product, Might Be a Novel Drug Candidate for Ischemic Stroke

Stroke ◽

10.1161/strokeaha.115.009687 ◽

2016 ◽

Vol 47 (1) ◽

pp. 187-195 ◽

Cited By ~ 28

Author(s):

Mei Li ◽

Zhi-Peng Zhou ◽

Meiling Sun ◽

Lijuan Cao ◽

Jieyu Chen ◽

...

Keyword(s):

Ischemic Stroke ◽

Pentose Phosphate Pathway ◽

Nicotinamide Adenine Dinucleotide ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Pentose Phosphate ◽

Nicotinamide Adenine ◽

Drug Candidate ◽

Reduced Nicotinamide Adenine Dinucleotide ◽

Novel Drug

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Increased nicotinamide adenine dinucleotide content and synthesis in Plasmodium falciparum-infected human erythrocytes

Blood ◽

10.1182/blood.v75.8.1705.bloodjournal7581705 ◽

1990 ◽

Vol 75 (8) ◽

pp. 1705-1710 ◽

Cited By ~ 1

Author(s):

CR Zerez ◽

EF Jr Roth ◽

S Schulman ◽

KR Tanaka

Keyword(s):

Plasmodium Falciparum ◽

Nicotinic Acid ◽

Nicotinamide Adenine Dinucleotide ◽

Biosynthetic Pathway ◽

Pentose Phosphate ◽

Nicotinamide Adenine ◽

Nicotinamide Phosphoribosyltransferase ◽

Nad Synthesis ◽

Infected Rbcs ◽

Nicotinic Acid Phosphoribosyltransferase

Plasmodium falciparum-infected red blood cells (RBCs) are characterized by increases in the activity of glycolytic enzymes. Because nicotinamide adenine dinucleotide (NAD) and NAD phosphate (NADP) are cofactors in the reactions of glycolysis and pentose phosphate shunt, we have examined NAD and NADP content in P. falciparum-infected RBCs. Although NADP content was not significantly altered, NAD content was increased approximately 10-fold in infected RBCs (66% parasitemia) compared with uninfected control RBCs. To determine the mechanism for the increase in NAD content, we examined the activity of several NAD biosynthetic enzymes. It is known that normal human RBCs make NAD exclusively from nicotinic acid and lack the capacity to make NAD from nicotinamide. We demonstrate that infected RBCs have readily detectable nicotinamide phosphoribosyltransferase (NPRT), the first enzyme in the NAD biosynthetic pathway that uses nicotinamide, and abundant nicotinamide deamidase, the enzyme that converts nicotinamide to nicotinic acid, thereby indicating that infected RBCs can make NAD from nicotinamide. In addition, infected RBCs have a threefold increase in nicotinic acid phosphoribosyltransferase (NAPRT), the first enzyme in the NAD biosynthetic pathway that uses nicotinic acid. Thus, the increase in NAD content in P falciparum-infected RBCs appears to be mediated by increases in NAD synthesis from both nicotinic acid and nicotinamide.

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Effect of Niacin on Mitochondria of Allium Cepa Root Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060404 ◽

1967 ◽

Vol 25 ◽

pp. 78-79

Author(s):

M. Arif Hayat

Keyword(s):

Nicotinamide Adenine Dinucleotide ◽

Hydrogen Transfer ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Nicotinamide Adenine ◽

Root Tips ◽

Root Cells ◽

Transfer Processes ◽

Standard Procedures ◽

A Cell ◽

Critical Interest

Although it is recognized that niacin (pyridine-3-carboxylic acid), incorporated as the amide in nicotinamide adenine dinucleotide (NAD) or in nicotinamide adenine dinucleotide phosphate (NADP), is a cofactor in hydrogen transfer in numerous enzyme reactions in all organisms studied, virtually no information is available on the effect of this vitamin on a cell at the submicroscopic level. Since mitochondria act as sites for many hydrogen transfer processes, the possible response of mitochondria to niacin treatment is, therefore, of critical interest.Onion bulbs were placed on vials filled with double distilled water in the dark at 25°C. After two days the bulbs and newly developed root system were transferred to vials containing 0.1% niacin. Root tips were collected at ¼, ½, 1, 2, 4, and 8 hr. intervals after treatment. The tissues were fixed in glutaraldehyde-OsO4 as well as in 2% KMnO4 according to standard procedures. In both cases, the tissues were dehydrated in an acetone series and embedded in Reynolds' lead citrate for 3-10 minutes.

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