Multiple independent L-gulonolactone oxidase (GULO) gene losses and vitamin C synthesis reacquisition events in non-Deuterostomian animal species

Introduction: L-gulonolactone oxidase (Gulo) is the rate limiting enzyme for Vitamin C (VitC) biosynthesis. Humans rely on dietary VitC for collagen synthesis, extracellular matrix formation, and tissue regeneration. VitC deficiency is an unrecognized condition and its role in cardiac homeostasis and post-acute myocardial infarction (AMI) remodeling is unknown. Hypothesis: Low levels of VitC impair cardiac function and tissue repair following AMI. Methods: Adult male Gulo -/- knockout mice (C57BL6 background, N=8) and control C57BL (N=8), which are able to synthesize VitC were used. VitC deficiency was maintained supplying low levels of VitC (30mg/l) to Gulo -/- mice in drinking water. Mice underwent M-mode and Doppler echocardiography to measure left ventricular (LV) diameters and wall thicknesses, fractional shortening (FS), E and A waves, E/A ratio, isovolumetric relaxation time (IRT) and myocardial performance index (MPI). Experimental AMI was induced by coronary artery ligation for 7 days. An additional group of Gulo -/- were mice supplemented with physiological levels of VitC (330 mg/l) and underwent AMI. Results: VitC deficient Gulo -/- mice exhibited significantly reduced LV wall thicknesses, reduced FS, and impaired diastolic function, measured as significantly reduced E/A ratio and longer IRT (Panel A, B & C). Following AMI, 100% (8/8) of deficient Gulo -/- mice died within 5 days. Supplementation with physiological levels of VitC significantly improved survival after AMI (Panel D). Conclusion: VitC deficiency impairs systolic and diastolic function. Moreover, VitC is critical for the post-AMI survival.

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Vitamin C in Plants: From Functions to Biofortification

Antioxidants ◽

10.3390/antiox8110519 ◽

2019 ◽

Vol 8 (11) ◽

pp. 519 ◽

Cited By ~ 9

Author(s):

Costantino Paciolla ◽

Stefania Fortunato ◽

Nunzio Dipierro ◽

Annalisa Paradiso ◽

Silvana De Leonardis ◽

...

Keyword(s):

Vitamin C ◽

Nutritional Value ◽

Plant Stress ◽

Free Radical Scavenger ◽

Multiple Roles ◽

Radical Scavenger ◽

Human Metabolism ◽

Physiological Processes ◽

Gene Coding ◽

Gulonolactone Oxidase

Vitamin C (l-ascorbic acid) is an excellent free radical scavenger, not only for its capability to donate reducing equivalents but also for the relative stability of the derived monodehydroascorbate radical. However, vitamin C is not only an antioxidant, since it is also a cofactor for numerous enzymes involved in plant and human metabolism. In humans, vitamin C takes part in various physiological processes, such as iron absorption, collagen synthesis, immune stimulation, and epigenetic regulation. Due to the functional loss of the gene coding for l-gulonolactone oxidase, humans cannot synthesize vitamin C; thus, they principally utilize plant-based foods for their needs. For this reason, increasing the vitamin C content of crops could have helpful effects on human health. To achieve this objective, exhaustive knowledge of the metabolism and functions of vitamin C in plants is needed. In this review, the multiple roles of vitamin C in plant physiology as well as the regulation of its content, through biosynthetic or recycling pathways, are analyzed. Finally, attention is paid to the strategies that have been used to increase the content of vitamin C in crops, emphasizing not only the improvement of nutritional value of the crops but also the acquisition of plant stress resistance.

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Evolution of alternative biosynthetic pathways for vitamin C following plastid acquisition in photosynthetic eukaryotes

eLife ◽

10.7554/elife.06369 ◽

2015 ◽

Vol 4 ◽

Cited By ~ 69

Author(s):

Glen Wheeler ◽

Takahiro Ishikawa ◽

Varissa Pornsaksit ◽

Nicholas Smirnoff

Keyword(s):

Vitamin C ◽

Biosynthetic Pathway ◽

Critical Role ◽

Biosynthetic Pathways ◽

Oxygen Species ◽

Photosynthetic Eukaryote ◽

Alternative Pathways ◽

Photosynthetic Eukaryotes ◽

Gulonolactone Oxidase ◽

Eukaryote Evolution

Ascorbic acid (vitamin C) is an enzyme co-factor in eukaryotes that also plays a critical role in protecting photosynthetic eukaryotes against damaging reactive oxygen species derived from the chloroplast. Many animal lineages, including primates, have become ascorbate auxotrophs due to the loss of the terminal enzyme in their biosynthetic pathway, l-gulonolactone oxidase (GULO). The alternative pathways found in land plants and Euglena use a different terminal enzyme, l-galactonolactone dehydrogenase (GLDH). The evolutionary processes leading to these differing pathways and their contribution to the cellular roles of ascorbate remain unclear. Here we present molecular and biochemical evidence demonstrating that GULO was functionally replaced with GLDH in photosynthetic eukaryote lineages following plastid acquisition. GULO has therefore been lost repeatedly throughout eukaryote evolution. The formation of the alternative biosynthetic pathways in photosynthetic eukaryotes uncoupled ascorbate synthesis from hydrogen peroxide production and likely contributed to the rise of ascorbate as a major photoprotective antioxidant.

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Intragenic deletion in the gene encoding L-gulonolactone oxidase causes vitamin C deficiency in pigs

Mammalian Genome ◽

10.1007/s00335-003-2324-6 ◽

2004 ◽

Vol 15 (4) ◽

pp. 323-333 ◽

Cited By ~ 14

Author(s):

Lara Hasan ◽

Peter V�geli ◽

Peter Stoll ◽

?pela ?pilar Gerald KramerStranzinger ◽

Stefan Neuenschwander

Keyword(s):

Vitamin C ◽

Gene Encoding ◽

Vitamin C Deficiency ◽

Intragenic Deletion ◽

Gulonolactone Oxidase

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Dynamic Alterations on Synthesis and Transportation of Vitamin C and Deposition Status in Produced Eggs Induced by Dietary Vitamin C Supplementation in Hy-Line Brown Layer Model

10.21203/rs.3.rs-38944/v1 ◽

2020 ◽

Author(s):

Yufei Zhu ◽

Jianfei Zhao ◽

Wei Guo ◽

Kailong Qin ◽

Jiakun Yan ◽

...

Keyword(s):

Vitamin C ◽

Dietary Vitamin ◽

Layer Model ◽

In Ovo ◽

Positive Effects ◽

Sodium Dependent ◽

Gulonolactone Oxidase ◽

Vitamin C Supplementation ◽

Liver And Kidney ◽

In Ovo Feeding

Abstract Background: Some previous studies have indicated that in ovo feeding (IOF) of vitamin C (VC) had positive effects on the performance in poultry. In order to realize embryonic VC supplementation, an idea about hen’s dietary VC supplementation to achieve VC enrichment in produced eggs was proposed. And this study was executed to investigate the effects of dietary VC supplementation on synthesis and transportation of VC in layers and VC deposition status in produced eggs.Results: Compared with Arbor Acres breeder eggs, egg VC content was lower in Isa Brown breeder eggs and Hy-Line Brown layer eggs (P < 0.05). Sodium-dependent vitamin C transporter 1 (SVCT1) and SVCT2 expression was higher in ileum than in duodenum and jejunum (P < 0.05). SVCT1 expression was extremely higher in magnum than in ovary, while SVCT2 expression was lower (P < 0.05). L-gulonolactone oxidase (GLO) expression was extremely higher and SVCT1 expression was higher in kidney than in liver, while SVCT2 was lower (P < 0.05). 400 mg/kg VC supplementation increased SVCT1 expression in duodenum, ovary and magnum, while decreased GLO and SVCT1 expression in liver (P < 0.05). 200 and 400 mg/kg VC supplementation increased SVCT2 expression in duodenum, while decreased GLO and SVCT1 expression in kidney and SVCT2 expression in liver (P < 0.05).Conclusions: Hy-Line Brown layer was a useful model for investigating effects of dietary VC supplementation on VC deposition in produced eggs. Dietary VC supplementation promoted VC absorption in duodenum and jejunum, but reduced endogenous VC synthesis in liver and kidney. Although dietary VC supplementation enhanced VC transportation in ovary and magnum, it finally failed to increase VC deposition in produced eggs.

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Restoration of vitamin C synthesis in transgenic Gulo-/- mice by helper-dependent adenoviral-based expression of gulonolactone oxidase.

Human Gene Therapy ◽

10.1089/hgt.2008.106 ◽

2008 ◽

Vol 0 (ja) ◽

pp. 081015093227032

Author(s):

Yi Li ◽

Chang Xin Shi ◽

Jack Rosenfeld ◽

Karen L. Mossman ◽

Yong Chool Boo ◽

...

Keyword(s):

Vitamin C ◽

Gulonolactone Oxidase

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Modification of analytical procedures for determining vitamin C enzyme (L-gulonolactone oxidase) activity in swine liver

The Journal of Nutritional Biochemistry ◽

10.1016/s0955-2863(02)00276-0 ◽

2003 ◽

Vol 14 (3) ◽

pp. 139-146 ◽

Cited By ~ 2

Author(s):

San Ching ◽

Donald C. Mahan ◽

R.égis Moreau ◽

Konrad Dabrowski

Keyword(s):

Vitamin C ◽

Oxidase Activity ◽

Gulonolactone Oxidase ◽

Swine Liver ◽

Analytical Procedures

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Spontaneous Fractures in the Mouse Mutant sfx Are Caused by Deletion of the Gulonolactone Oxidase Gene, Causing Vitamin C Deficiency

Journal of Bone and Mineral Research ◽

10.1359/jbmr.050406 ◽

2005 ◽

Vol 20 (9) ◽

pp. 1597-1610 ◽

Cited By ~ 33

Author(s):

Subburaman Mohan ◽

Anil Kapoor ◽

Anny Singgih ◽

Zhang Zhang ◽

Tim Taylor ◽

...

Keyword(s):

Vitamin C ◽

Mouse Mutant ◽

Oxidase Gene ◽

Vitamin C Deficiency ◽

Gulonolactone Oxidase

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Farmacologia e toxicologia do ácido ascórbico: uma revisão

Ciência e Natura ◽

10.5902/2179460x27114 ◽

2000 ◽

Vol 22 (22) ◽

pp. 103

Author(s):

Maria Caroline Jacques da Silva

Keyword(s):

Ascorbic Acid ◽

Vitamin C ◽

Daily Intake ◽

Nutritional Supplement ◽

Vitamin Supplement ◽

Human Beings ◽

Green Pepper ◽

Oxidation Reduction ◽

Enzymatic Systems ◽

Gulonolactone Oxidase

L-Ascorbic acid (AA) or vitamin C is a six carbon cetolactone, structurally related to glucose and other hexoses. The major sources of AA are citrus fruits, strawberry, melon, green pepper, potato, tomato and leafy green vegetables. AA interferes with a broad spectrum of oxidation-reduction reactions, acting in at least 10 enzymatic systems. In this way, vitamin C influences the synthesis of collagen, carnitine, and neurotransmitters; the transformation of cholesterol into bile acids; biotransformation of xenobiotics substances; absorption of iron; and formation and scavenging of oxygen free radicals. AA is used as food addictive because of its antioxidant properties.Therapeutically, it is used as nutritional supplement during scurvy. Human beings and other primates, as well as guinea pigs and some species of bats are mammals that are unable to synthesize AA; thus, they need AA in the diet to prevent scurvy. Rats are able to synthesize AA using glucose, through intermediary formation of D-glucuronic acid, L-gulonic acid and gulonolactone.Homo sapiens lack the hepatic enzyme gulonolactone oxidase, which catalyses the last reaction of the biosynthesis pathway (L-gulonolactone conversion to ascorbic acid). The functions of central nervous, immune, and cardiovascular systems, and the periodontal tissue, as well as the detoxification function of the liver, are negatively influenced by vitamin C deficiency. In this way, it has been described several benefits of vitamin supplement ingestion, as decreasing of LDL cholesterol, including mega doses that can reach as much as 18g daily. Although there have been raised many literatures about vitamin C use in a wide variety of diseases, there is a lack of clinical efficiency of mega doses; besides, some side effects can come up, as diarrhea and oxalate stones in the kidneys. However, the ideal daily intake of vitamin C is still unknown. This happen because the recommended daily intake is based in a single role of AA, the scurvy prevention. Daily ingestion of AA should be the same quantity excreted or destroyed by oxidation, taking into consideration AA actions on the enzymatic systems. Actually, vitamin C is necessary for health in little quantities and is harmful in large doses. It happens because the cells are always walking a balance between oxidation and reduction processes, and AA in great quantities assume oxidative characteristics, interfering in this balance. Although the existence of several evidences indicating AA toxicity in large doses, there are some authors who believe that the ingestion of large doses is safe, but they admit that the disposable data are very contradictory.

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The terminal step in vitamin C biosynthesis in Trypanosoma cruzi is mediated by a FMN-dependent galactonolactone oxidase

Biochemical Journal ◽

10.1042/bj20070766 ◽

2007 ◽

Vol 407 (3) ◽

pp. 419-426 ◽

Cited By ~ 25

Author(s):

Flora J. Logan ◽

Martin C. Taylor ◽

Shane R. Wilkinson ◽

Harparkash Kaur ◽

John M. Kelly

Keyword(s):

Vitamin C ◽

Trypanosoma Cruzi ◽

Trypanosoma Brucei ◽

Biosynthetic Pathway ◽

Site Directed Mutagenesis ◽

Binding Motif ◽

Cofactor Binding ◽

Tryptophan Residues ◽

Gulonolactone Oxidase ◽

Flavin Binding

Humans lack the ability to synthesize vitamin C (ascorbate) due to the absence of gulonolactone oxidase, the last enzyme in the biosynthetic pathway in most other mammals. The corresponding oxidoreductase in trypanosomes therefore represents a target that may be therapeutically exploitable. This is reinforced by our observation that Trypanosoma cruzi, the causative agent of Chagas' disease, lacks the capacity to scavenge ascorbate from its environment and is therefore dependent on biosynthesis to maintain intracellular levels of this vitamin. Here, we show that T. cruzi galactonolactone oxidase (TcGAL) can utilize both L-galactono-γ-lactone and D-arabinono-γ-lactone as substrates for synthesis of vitamin C, in reactions that obey Michaelis–Menten kinetics. It is >20-fold more active than the analogous enzyme from the African trypanosome Trypanosoma brucei. FMN is an essential cofactor for enzyme activity and binds to TcGAL non-covalently. In other flavoproteins, a histidine residue located within the N-terminal flavin-binding motif has been shown to be crucial for cofactor binding. Using site-directed mutagenesis, we show that the corresponding residue in TcGAL (Lys-55) is not essential for this interaction. In contrast, we find that histidine and tryptophan residues (His-447 and Trp-448), localized within a C-terminal motif (HWXK) that is a feature of ascorbate-synthesizing enzymes, are necessary for the FMN association. The conserved lysine residue within this motif (Lys-450) is not required for cofactor binding, but its replacement by glycine renders the protein completely inactive.

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