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The AtlasAmino acidsPolar, uncharged

AsparagineAsn · N

The amide of aspartate: the anchor for sugars on proteins, the amino acid childhood leukemia is starved of, and the precursor of the acrylamide in chips.

Status Reference · not yet an episodeSources 31Reviewed October 2026
Structural formula of Asparagine, C4H8N2O3.
Skeletal formula — every corner and every line end is a carbon, and the hydrogens on carbon are left implied.

Molecule · Asn · 9 heavy atoms

Asparagine

C4H8N2O3132.12 g/mol

The amide of aspartate: the anchor for sugars on proteins, the amino acid childhood leukemia is starved of, and the precursor of the acrylamide in chips.

Built fromthe charted ones open their own entry

Codes
Asn · N
Formula
C4H8N2O3
Molar mass
132.12 g/mol
Systematic name
(2S)-2,4-diamino-4-oxobutanoic acid
Side chain
Carbamoylmethyl: one carbon and an amide; polar and uncharged.
Class
Polar, uncharged
In the diet
Dispensable
Carbon skeleton
Glucogenic
pKa
α-COOH 2.02 · α-NH3+ 8.80
Isoelectric point
pH 5.41
Hydropathy
-3.5 (Kyte–Doolittle)
Codons
AAU AAC

pKa and isoelectric point: Nelson and Cox, Lehninger Principles of Biochemistry, table of amino acid properties (free amino acid, 25 °C). Hydropathy: Kyte and Doolittle, J Mol Biol 1982. Essentiality: Reeds, J Nutr 2000. Formula and mass computed from the structure.

In brief

What it is

Aspartate with its side-chain acid turned into an amide: a short, polar, uncharged side chain. The body makes it from aspartate and glutamine with asparagine synthetase 1.

Why it matters

Asparagine is where most sugars are attached to proteins, at Asn-X-Ser/Thr sequences 2. Leukemic lymphoblasts depend on it from the blood, which is why asparaginase, an enzyme that destroys it, is a core drug for childhood acute lymphoblastic leukemia 3,4.

Where it runs short

The brain needs to make its own: children with asparagine synthetase deficiency are born with small heads and develop seizures and progressive brain atrophy, while other organs are spared 1,5.

Where it turns

In food, heated with reducing sugars above about 120 °C, asparagine is the main source of acrylamide, a probable human carcinogen, in fried potatoes and baked cereals 6,7.

In the body the risk is too little; in the frying pan, too much.

The molecule

Asparagine is aspartate with its side-chain carboxylic acid replaced by an amide. The amide is polar but uncharged, and can both give and accept hydrogen bonds.

That amide is not permanent. In proteins asparagine slowly loses it, deamidating to aspartate or isoaspartate, at a rate set by its neighbors; measured across 306 sequences, the rates vary enough that deamidation has been proposed as a built-in molecular timer of protein age 8. A repair enzyme handles the damage, and mice without it die young 9.

Charge · pHAsparagine carries almost no net charge at the pH of blood.
+2+10-1-202468101214Blood · pH 7.4pI 5.41pHNet charge

Move across the chart to read the charge at any pH.

Computed from its pKa values (α-carboxyl 2.02, α-amino 8.80) by the Henderson–Hasselbalch equation, for the free amino acid in water at 25 °C. Inside a folded protein the same groups can shift by a unit or more. The faint lines are the other amino acids.

HydropathyAsparagine scores -3.5: the 6th most water-loving of the twenty.
-4-20+2+4Arginine, -4.5RLysine, -3.9KAspartate, -3.5DGlutamate, -3.5EAsparagine, -3.5NGlutamine, -3.5QHistidine, -3.2HProline, -1.6PTyrosine, -1.3YTryptophan, -0.9WSerine, -0.8SThreonine, -0.7TGlycine, -0.4GAlanine, +1.8AMethionine, +1.9MCysteine, +2.5CPhenylalanine, +2.8FLeucine, +3.8LValine, +4.2VIsoleucine, +4.5I← Water-lovingWater-avoiding →

Kyte–Doolittle hydropathy index: positive values avoid water and tend to be buried inside a folded protein, negative values sit on its surface. Each letter is an amino acid; choose one to open it.

The genetic codeAsparagine has 2 codons. The code is redundant, so most single-letter changes at the third position still write asparagine.
The 64 codons of the standard genetic code. Codons for asparagine are marked.
1st ↓  2nd →UCAG3rd
UUUUPheUCUSerUAUTyrUGUCysU
UUCPheUCCSerUACTyrUGCCysC
UUALeuUCASerUAAStopUGAStopA
UUGLeuUCGSerUAGStopUGGTrpG
CCUULeuCCUProCAUHisCGUArgU
CUCLeuCCCProCACHisCGCArgC
CUALeuCCAProCAAGlnCGAArgA
CUGLeuCCGProCAGGlnCGGArgG
AAUUIleACUThrAAUAsnAGUSerU
AUCIleACCThrAACAsnAGCSerC
AUAIleACAThrAAALysAGAArgA
AUGMetACGThrAAGLysAGGArgG
GGUUValGCUAlaGAUAspGGUGlyU
GUCValGCCAlaGACAspGGCGlyC
GUAValGCAAlaGAAGluGGAGlyA
GUGValGCGAlaGAGGluGGGGlyG

Where it comes from

Asparagine synthetase makes asparagine from aspartate, taking the amide nitrogen from glutamine and spending ATP. It is present in most organs but at very different levels, and its expression rises sharply under cellular stress, through a single gene on chromosome 7 1.

The brain is the one organ that cannot do without it: inherited loss of the enzyme damages the developing brain while leaving other organs normal 5.

DispensableMade from aspartate and glutamine by asparagine synthetase, present in most organs; the brain depends on its own synthesis 1,5.

How much

None; the body makes it 1.

Where it is in food

  • Potatoes and cereals are rich in free asparagine, which is why they form the most acrylamide when fried or baked 6.

In the bottle · synthetic or enzymaticAsparagine is made by low-yield extraction from plants, by chemical synthesis, or increasingly with asparagine synthetase in engineered bacteria, coupled to systems that regenerate ATP 10.

What the body does with it

Asparagine is the attachment point for N-linked sugars. The chains are assembled on a lipid carrier and then transferred en bloc to asparagines in the sequence Asn-X-Ser/Thr; this is essential in all eukaryotes and shapes how most secreted and membrane proteins fold and work 2.

In cancer, asparagine is a dependency. The finding goes back to 1953, when serum from guinea pigs, but not from horses or rabbits, made transplanted lymphomas regress in mice 11; the active agent was asparaginase, now made from Escherichia coli and Erwinia chrysanthemi 3. In a mouse model of breast cancer, cutting asparagine by asparaginase, by knocking down its synthetase or by diet reduced metastasis without slowing the primary tumor 12.

The dependency is not only a cancer cell's. Senescent cells — the ones that stop dividing and will not die, and that accumulate with age — turn out to downregulate asparagine synthetase sharply, which leaves them relying on asparagine from outside exactly as a leukemic blast does. Asparaginase together with an autophagy inhibitor removes them, because the two block the outside supply and the inside salvage route at once 13. It is the same vulnerability, found in a cell type nobody was looking at.

And how much asparagine a tumor actually sees is not settled by the plate. In mice, the Bacteroides gene bo-ansB consumes asparagine in the intestine, and whether dietary asparagine changed colorectal tumor progression depended on whether the gene was there 14. A second mouse study found the effect of injected asparagine on colorectal tumor growth differed by sex, running through 17β-oestradiol and aromatase 15. Both are mouse work, and both say the same thing about the human version of the question: the dose that reaches the tumor is not the dose on the label.

In three sentences each

The sugar anchor

Oligosaccharyltransferase transfers a pre-assembled sugar block onto asparagines in the sequence Asn-X-Ser/Thr, where X is anything but proline; this N-glycosylation is essential in all eukaryotes 2.

Starving leukemia

Asparaginase hydrolyzes blood asparagine to aspartate and ammonia; lymphoblasts that cannot make enough of their own die, and those that switch on asparagine synthetase resist the drug 1,3.

Acrylamide in the Maillard reaction

Heated with reducing sugars, asparagine’s backbone breaks down to acrylamide; asparagine is a major amino acid in potatoes and cereals, which is why their fried and baked products carry the most 6,7.

How it is made, moved and broken down

Asparaginase splits asparagine into aspartate and ammonia 3. Leukemia cells that resist the drug turn on asparagine synthetase and a wider amino acid stress response driven by the transcription factor ATF4 1,16. Whether that switch can be read in advance is the biomarker question, and the most recent answer is a careful no: in patient-derived models of hepatocellular carcinoma, hypermethylation of the asparagine synthetase promoter was required for sensitivity to calaspargase pegol and was not sufficient to predict it 17.

Carbon skeleton · glucogenicAsparaginase turns it into aspartate, which becomes oxaloacetate 3,18.

Made and destroyedSynthetase builds it; asparaginase is the drug that undoes it 1,3.
  1. Aspartate + glutamine
  2. Asparagine synthetaseASNS · ATP
  3. Asparagine + glutamate
  4. AsparaginaseASPG (drug: bacterial)
  5. Aspartate + NH₃
N-glycosylationIn the endoplasmic reticulum 2.
  1. Asn in Asn-X-Ser/Thr + lipid-linked sugar
  2. OligosaccharyltransferaseSTT3A, STT3B
  3. N-glycoprotein
In the fryerWith reducing sugars at high temperature 6,7.
  1. Asparagine + glucose
  2. The Maillard reactionheat
  3. Acrylamide

Where it matters most

Brain
Depends on making its own asparagine 5.
Leukemic lymphoblasts
Depend on asparagine from blood, the basis of asparaginase therapy 3.
Every secretory cell
N-glycosylation of asparagines in the endoplasmic reticulum 2.

When it goes wrong

Inherited

Asparagine synthetase deficiency

ASNS · autosomal recessive

Congenital microcephaly, intellectual disability, progressive cerebral atrophy and intractable seizures, described in four families in 2013 5; by 2017, 15 mutations had been linked to it 1. Supplementing the missing amino acid is the obvious treatment and the evidence for it is one case at a time: a 2026 report of a preterm infant with congenital microcephaly and early-onset myoclonic epilepsy adds its experience to a therapeutic literature the authors describe as limited and heterogeneous 19. For a disorder this rare, that is not a criticism of the work; it is the state of the evidence, and a family deciding about treatment is entitled to know it.

How it is foundExome sequencing; plasma asparagine may be low but is not always 5.

Drug

Asparaginase in acute lymphoblastic leukemia

A core drug of treatment, with survival in childhood ALL now above 90% 20. Its toxicities are allergy and silent inactivation by antibodies 4, pancreatitis, which among 465 children with it needed mechanical ventilation in 8% 20, and thrombosis, in 5.2% of 1,752 children across 17 studies 21.

How it is foundNadir serum asparaginase activity 4.

Drug

Switching asparaginase after allergy

Erwinia asparaginase is antigenically distinct from the E. coli forms. Intravenous Erwinia reached adequate activity in 83% of patients 48 hours after a dose 22, and a recombinant Erwinia product reached it in 90 to 96% 23. What the switch is FOR has recently been clarified, and it is not what the strategy assumed: the hypersensitivity is now attributed to anti-PEG antibodies rather than to antibodies against the enzyme itself, which is why it can appear on first exposure and why desensitization and therapeutic drug monitoring, not only a change of organism, are part of the current answer 24.

How it is foundNadir serum asparaginase activity 23.

Association

Dietary acrylamide

Acrylamide forms in fried and oven-cooked foods from asparagine and sugars 6. It is classified as probably carcinogenic to humans; asparaginase pre-treatment of potato reduced it by more than 80% 6,25.

Drug

How much asparaginase is enough

The drug works, and for twenty years the answer to every question about it was more of it. JCCG ALL-B12 enrolled 1,936 children aged 1 to 19 with newly diagnosed B-cell leukemia and randomized within risk groups rather than across them. Five-year event-free survival was 85.2% and overall survival 94.3% — and asparaginase intensification in the intermediate-risk group had limited effect, dexamethasone pulses in the standard-risk group no significant benefit, and high-dose methotrexate in the high-risk group no advantage over block therapy. The authors' own conclusion is that improvement from intensifying chemotherapy has reached a plateau 26.

How it is foundEvent-free survival, and serum asparaginase activity to confirm the drug is still working rather than silently inactivated 26.

Drug

Asparaginase-associated hyperammonemia

Splitting asparagine releases ammonia, so the drug raises it by design. Whether that matters has only ever been described in small case series, which range from an asymptomatic laboratory finding to encephalopathy; the true frequency and the long-term importance are both unknown 27. It is worth naming for the same reason as any toxicity that is only ever a case report: the absence of a denominator is not the absence of a problem.

How it is foundPlasma ammonia, measured when a child on asparaginase becomes confused rather than routinely 27.

How it is measured

During asparaginase treatment, what is measured is the drug’s activity in serum, because asparagine itself keeps being destroyed after the blood is drawn 4,28. Recombinant Erwinia asparaginase given three times a week kept nadir activity above 0.1 IU/mL in 90 to 96% of patients in its pivotal trial 23.

  • Serum asparaginase activityThe standard way to check that asparaginase is working, as a nadir level before the next dose 4.A nadir of at least 0.1 IU/mL is the accepted target; it detects silent inactivation, where antibodies neutralize the drug without an allergic reaction 4,23.It measures the enzyme, not the asparagine it removes.
  • Plasma asparagine during asparaginaseDirectly shows depletion 28.The drug keeps destroying asparagine in the tube; even immediate cooling does not stop it, so samples need an enzyme inhibitor or the result will be falsely low 28.

Food, supplements and the evidence

Establishedreplicated in people, for a named outcome

  • Asparaginase is a core drug in childhood acute lymphoblastic leukemia 3,4.
  • Asparaginase treatment of food cuts acrylamide formation 25.
  • Asparaginase is more effective at removing acrylamide from baked goods than the botanical alternatives. In a cookie model, the control carried 215 µg/kg, partial replacement of wheat flour with apple pomace brought that to 132, and asparaginase to 65 29.

Uncertainsmall, short, mixed, surrogate or preclinical

  • Dietary asparagine restriction to limit cancer spread: shown in a mouse model of breast cancer, not in people 12.
  • What dietary acrylamide is worth doing about. The same cookie study ran a Monte Carlo exposure assessment and found the margin of exposure for children stayed below 10,000 — the threshold below which a genotoxic carcinogen is treated as a concern — even after the reductions 29, while the largest prospective evidence on the food that carries most of it finds nothing 30. Those two can both be true: a margin of exposure is a precautionary calculation, not an observed risk.

Sold asthe claim on the label, against the evidence

  • Nothing in this column.

What is strange about it

The leukemia drug was found by accident, in guinea pig blood: in 1953 normal guinea pig serum made mouse lymphomas regress, and horse and rabbit serum did not 11.

Food makers now treat raw potatoes and dough with asparaginase, the leukemia drug’s enzyme, which cut acrylamide in chips and baked goods by more than 80% 25.

Asparagine is named after asparagus, but the smell asparagus gives to urine is sulfurous, and both producing and smelling it vary between people; not being able to smell it goes with a variant in a cluster of olfactory receptor genes 31.

The acrylamide story has a second half that the first half rarely gets told with. Acrylamide forms when asparagine meets a reducing sugar at baking temperature, it is a probable human carcinogen, and treating dough with asparaginase removes most of it. Bread is the single largest dietary source — and a systematic review and meta-analysis of prospective cohorts covering 1,887,074 adults found no association between bread intake and cancer. Of 108 reported hazard ratios, 97 were either not significant or pointed the other way, and the pooled estimate for site-specific cancer was 1.01 (95% CI 0.89 to 1.14) 30. The chemistry is real, the mitigation works, and the epidemiology has not found the harm it was mitigating.

Where it connects

Topics on the map

On the map

A star in The rest of the amino acids, one of 6. Leukemia cells cannot make it, so a bacterial enzyme that destroys it in the blood is a core leukemia drug. Named after asparagus, where it was first found.

Find it on the map

Sources

31 sources, numbered as they are cited. Every one was checked against PubMed or its publisher before it was cited here; the note under each says what it shows and what it does not.

  1. 1
    Lomelino CL, Andring JT, McKenna R, et al. Asparagine synthetase: function, structure, and role in disease.J Biol Chem · 2017 · 292(49):19952–19958doi:10.1074/jbc.R117.819060 · PMID 29084849

    Review; stress-induced expression; asparaginase resistance; 15 mutations.

  2. 2
    Kohda D. Structural basis of protein Asn-glycosylation by oligosaccharyltransferases.Adv Exp Med Biol · 2018 · 1104:171–199doi:10.1007/978-981-13-2158-0_9 · PMID 30484249

    N-glycosylation at Asn-X-Ser/Thr.

  3. 3
    Thakur M, Tiwari SK, Bansal S. L-asparaginase: a review of microbial production and protein engineering with translational applications for oncology and food safety.World J Microbiol Biotechnol · 2025 · 41(10):389doi:10.1007/s11274-025-04614-1 · PMID 41099876

    Review; E. coli and Erwinia formulations; acrylamide use.

  4. 4
    van der Sluis IM, Vrooman LM, Pieters R, et al. Consensus expert recommendations for identification and management of asparaginase hypersensitivity and silent inactivation.Haematologica · 2016 · 101(3):279–285doi:10.3324/haematol.2015.137380 · PMID 26928249

    Activity monitoring and switching preparations.

  5. 5
    Ruzzo EK, Capo-Chichi JM, Ben-Zeev B, et al. Deficiency of asparagine synthetase causes congenital microcephaly and a progressive form of encephalopathy.Neuron · 2013 · 80(2):429–441doi:10.1016/j.neuron.2013.08.013 · PMID 24139043

    Four families; brain-specific dependence.

  6. 6
    Mottram DS, Wedzicha BL, Dodson AT. Acrylamide is formed in the Maillard reaction.Nature · 2002 · 419(6906):448–449doi:10.1038/419448a · PMID 12368844

    Asparagine as the crucial participant.

  7. 7
    Stadler RH, Blank I, Varga N, et al. Acrylamide from Maillard reaction products.Nature · 2002 · 419(6906):449–450doi:10.1038/419449a · PMID 12368845

    Released from asparagine with reducing sugars.

  8. 8
    Robinson NE, Robinson AB. Molecular clocks.Proc Natl Acad Sci U S A · 2001 · 98(3):944–949doi:10.1073/pnas.98.3.944 · PMID 11158575

    Deamidation rates of 306 asparagine sequences.

  9. 9
    Kim E, Lowenson JD, MacLaren DC, et al. Deficiency of a protein-repair enzyme results in the accumulation of altered proteins, retardation of growth, and fatal seizures in mice.Proc Natl Acad Sci U S A · 1997 · 94(12):6132–6137doi:10.1073/pnas.94.12.6132 · PMID 9177182

    Mice without the repair enzyme.

  10. 10
    Luo W, Xu J, Chen H, et al. Synthesis of L-asparagine catalyzed by a novel asparagine synthase coupled with an ATP regeneration system.Front Bioeng Biotechnol · 2021 · 9:747404doi:10.3389/fbioe.2021.747404 · PMID 34631686

    Extraction, chemical and enzymatic routes.

  11. 11
    Kidd JG. Regression of transplanted lymphomas induced in vivo by means of normal guinea pig serum. I. Course of transplanted cancers of various kinds in mice and rats given guinea pig serum, horse serum, or rabbit serum.J Exp Med · 1953 · 98(6):565–582doi:10.1084/jem.98.6.565 · PMID 13109110

    The original observation.

  12. 12
    Knott SRV, Wagenblast E, Khan S, et al. Asparagine bioavailability governs metastasis in a model of breast cancer.Nature · 2018 · 554(7692):378–381doi:10.1038/nature25465 · PMID 29414946

    Mouse model.

  13. 13
    Huang Z, Liu X, Zhou X, et al. Asparaginase and autophagy inhibitors effectively remove senescent cells by synergistically limiting asparagine supply.Aging Cell · 2025 · 24(10):e70203doi:10.1111/acel.70203 · PMID 40905331

    The same dependency as the leukemic blast, in a cell that is not dividing at all.

  14. 14
    Qiao S, Li TT, Jeong M, et al. Microbiota utilization of intestinal amino acids modulates cancer progression and anticancer immunity.Cell Host Microbe · 2026 · 34(1):18–34.e14doi:10.1016/j.chom.2025.12.003 · PMID 41483801

    A single bacterial gene standing between what is eaten and what the tumor gets.

  15. 15
    Aladelokun O, Benitez K, Wang Y, et al. Sex-specific effects of exogenous asparagine on colorectal tumor growth, 17β-estradiol levels, and aromatase.Pharmacol Res · 2025 · 215:107736doi:10.1016/j.phrs.2025.107736 · PMID 40228761

    Mice, and a reminder that a dietary amino acid can act through a hormone.

  16. 16
    Ferguson DC, McCorkle JR, Barnett KR, et al. Amino acid stress response genes promote L-asparaginase resistance in pediatric acute lymphoblastic leukemia.Blood Adv · 2022 · 6(11):3386–3397doi:10.1182/bloodadvances.2022006965 · PMID 35671062

    ATF4 targets in resistance.

  17. 17
    Tyagi E, Pohorecka M, Valour D, et al. Asparagine synthetase promoter hypermethylation is required, but not sufficient, for sensitivity to Asparlas in patient-derived models of hepatocellular carcinoma.Eur J Pharmacol · 2025 · 1007:178241doi:10.1016/j.ejphar.2025.178241 · PMID 41082994

    Required but not sufficient: the four words that end most biomarker programs.

  18. 18
    Borst P. The malate-aspartate shuttle (Borst cycle): how it started and developed into a major metabolic pathway.IUBMB Life · 2020 · 72(11):2241–2259doi:10.1002/iub.2367 · PMID 32916028

    Aspartate and oxaloacetate.

  19. 19
    Yıldırım T, Selamioğlu A, Altaş MH, et al. Asparagine synthetase deficiency: clinical features and experience with asparagine supplementation.J Pediatr Endocrinol Metab · 2026doi:10.1515/jpem-2026-0234 · PMID 42568280

    One infant, and the whole of the therapeutic literature is case reports like it.

  20. 20
    Wolthers BO, Frandsen TL, Baruchel A, et al. Asparaginase-associated pancreatitis in childhood acute lymphoblastic leukaemia: an observational Ponte di Legno Toxicity Working Group study.Lancet Oncol · 2017 · 18(9):1238–1248doi:10.1016/S1470-2045(17)30424-2 · PMID 28736188

    465 children with pancreatitis from 26 trials.

  21. 21
    Caruso V, Iacoviello L, Di Castelnuovo A, et al. Thrombotic complications in childhood acute lymphoblastic leukemia: a meta-analysis of 17 prospective studies comprising 1752 pediatric patients.Blood · 2006 · 108(7):2216–2222doi:10.1182/blood-2006-04-015511 · PMID 16804111

    Thrombosis in 5.2%.

  22. 22
    Vrooman LM, Kirov II, Dreyer ZE, et al. Activity and toxicity of intravenous Erwinia asparaginase following allergy to E. coli-derived asparaginase in children and adolescents with acute lymphoblastic leukemia.Pediatr Blood Cancer · 2016 · 63(2):228–233doi:10.1002/pbc.25757 · PMID 26376459

    30 patients.

  23. 23
    Maese L, Loh ML, Choi MR, et al. Recombinant Erwinia asparaginase (JZP458) in acute lymphoblastic leukemia: results from the phase 2/3 AALL1931 study.Blood · 2023 · 141(7):704–712doi:10.1182/blood.2022016923 · PMID 36108304

    167 patients; adequate activity in 90–96% in the chosen schedule. Manufacturer-sponsored.

  24. 24
    Prelog T, Kavčič M, Ivancan S, et al. Hypersensitivity to PEG-asparaginase and desensitization strategies in pediatric acute lymphoblastic leukemia: a narrative review.Acta Med Acad · 2026doi:10.5644/ama2006-124.516 · PMID 42751926

    The allergy is to the polymer, not to the enzyme — which changes what switching products is meant to achieve.

  25. 25
    Jana A, Biswas S, Ghosh R, et al. Recent advances in L-asparaginase enzyme production and formulation development for acrylamide reduction during food processing.Food Chem X · 2024 · 25:102055doi:10.1016/j.fochx.2024.102055 · PMID 39758072

    More than 80% acrylamide reduction with enzyme pre-treatment.

  26. 26
    Kato M, Okamoto Y, Imamura T, et al. JCCG ALL-B12: evaluation of intensified therapies with vincristine/dexamethasone pulses and asparaginase and augmented high-dose methotrexate for pediatric B-ALL.J Clin Oncol · 2024 · 43(5):567–577doi:10.1200/JCO.24.00811 · PMID 39531610

    1,936 children, randomized within risk groups, and the sentence the field needed: intensification has reached a plateau.

  27. 27
    Raja RA, Als-Nielsen B, Lund AM, et al. Asparaginase-associated hyperammonemia.Haematologica · 2025 · 110(8):1702–1709doi:10.3324/haematol.2025.287301 · PMID 40270200

    A toxicity known only from small case series, which is a statement about the surveillance as much as the drug.

  28. 28
    Lanvers-Kaminsky C, Westhoff PS, D’Incalci M, et al. Immediate cooling does not prevent the ex vivo hydrolysis of L-asparagine by asparaginase.Ther Drug Monit · 2014 · 36(4):549–552doi:10.1097/FTD.0000000000000030 · PMID 24342897

    Ex vivo destruction of asparagine in the tube.

  29. 29
    Sevim S, Macit A, Faría MA, et al. Influence of apple pomace and asparaginase on acrylamide levels in cookies and behavior during simulated gastric digestion: risk assessment perspectives.Food Res Int · 2026 · 242(Pt 2):119880doi:10.1016/j.foodres.2026.119880 · PMID 42632667

    The enzyme beat the botanical, and the children's margin of exposure stayed below the threshold anyway.

  30. 30
    Gaesser GA, Angadi SS, Paterson C, et al. Bread consumption and cancer risk: systematic review and meta-analysis of prospective cohort studies.Curr Dev Nutr · 2024 · 8(12):104501doi:10.1016/j.cdnut.2024.104501 · PMID 39668947

    1,887,074 adults. The food that carries the most dietary acrylamide, and no signal.

  31. 31
    Pelchat ML, Bykowski C, Duke FF, et al. Excretion and perception of a characteristic odor in urine after asparagus ingestion: a psychophysical and genetic study.Chem Senses · 2011 · 36(1):9–17doi:10.1093/chemse/bjq081 · PMID 20876394

    Individual differences in producing and smelling the odor.

This is education, not medical advice. Nothing on this page is written with knowledge of your history, your medications or your risks, and nothing here is a dose. Do not start or stop any treatment on the basis of it — talk to your own physician. Read the full medical disclaimer.

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