Skip to main content
Log in

A review of the relationship between the gut microbiota and amino acid metabolism

  • Review Article
  • Published:
Amino Acids Aims and scope Submit manuscript

Abstract

New evidence has emerged in recent years to suggest a strong link between the human gut microbiota, its metabolites, and various physiological aspects of hosts along with important pathophysiological dimensions of diseases. The research indicates that the gut microbiota can facilitate metabolite production in two ways: first, the resident species of the gut microbiota use the amino acids produced from food or the host as elements for protein synthesis, and second, conversion or fermentation are used to drive nutrient metabolism. Additionally, the gut microbiota can synthesize several nutritionally essential amino acids de novo, which is a potential regulatory factor in amino acid homeostasis. The primary objective of this review is to summarize the current literature relating to the ways in which microbial amino acids contribute to host amino acid homeostasis.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1

Similar content being viewed by others

References

  • Backhed F, Manchester JK, Semenkovich CF, Gordon JI (2007) Mechanisms underlying the resistance to diet-induced obesity in germ-free mice. Proc Natl Acad Sci USA 104(3):979–984. doi:10.1073/pnas.0605374104

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Brinkworth GD, Noakes M, Clifton PM, Bird AR (2009) Comparative effects of very low-carbohydrate, high-fat and high-carbohydrate, low-fat weight-loss diets on bowel habit and faecal short-chain fatty acids and bacterial populations. Br J Nutr 101(10):1493–1502. doi:10.1017/S0007114508094658

    Article  CAS  PubMed  Google Scholar 

  • Christ B, Bruckner S, Winkler S (2015) The therapeutic promise of mesenchymal stem cells for liver restoration. Trends Mol Med 21(11):673–686. doi:10.1016/j.molmed.2015.09.004

    Article  PubMed  Google Scholar 

  • Ciarlo E, Heinonen T, Herderschee J, Fenwick C, Mombelli M, Le Roy D, Roger T (2016) Impact of the microbial derived short chain fatty acid propionate on host susceptibility to bacterial and fungal infections in vivo. Sci Rep UK. doi:10.1038/srep37944

    Google Scholar 

  • Collado MC, Isolauri E, Laitinen K, Salminen S (2008) Distinct composition of gut microbiota during pregnancy in overweight and normal-weight women. Am J Clin Nutr 88(4):894–899

    CAS  PubMed  Google Scholar 

  • Collins SM, Surette M, Bercik P (2012) The interplay between the intestinal microbiota and the brain. Nat Rev Microbiol 10(11):735–742. doi:10.1038/nrmicro2876

    Article  CAS  PubMed  Google Scholar 

  • Dai ZL, Wu G, Zhu WY (2011) Amino acid metabolism in intestinal bacteria: links between gut ecology and host health. Front Biosci (Landmark Ed) 16:1768–1786

    Article  CAS  Google Scholar 

  • Dai Z, Wu Z, Hang S, Zhu W, Wu G (2015) Amino acid metabolism in intestinal bacteria and its potential implications for mammalian reproduction. Mol Hum Reprod 21(5):389–409. doi:10.1093/molehr/gav003

    Article  CAS  PubMed  Google Scholar 

  • Davila AM, Blachier F, Gotteland M, Andriamihaja M, Benetti PH, Sanz Y, Tome D (2013) Re-print of “Intestinal luminal nitrogen metabolism: role of the gut microbiota and consequences for the host”. Pharmacol Res 69(1):114–126. doi:10.1016/j.phrs.2013.01.003

    Article  PubMed  Google Scholar 

  • De Filippo C, Cavalieri D, Di Paola M, Ramazzotti M, Poullet JB, Massart S, Collini S, Pieraccini G, Lionetti P (2010) Impact of diet in shaping gut microbiota revealed by a comparative study in children from Europe and rural Africa. Proc Natl Acad Sci USA 107(33):14691–14696. doi:10.1073/pnas.1005963107

    Article  PubMed  PubMed Central  Google Scholar 

  • Diaz Heijtz R, Wang S, Anuar F, Qian Y, Bjorkholm B, Samuelsson A, Hibberd ML, Forssberg H, Pettersson S (2011) Normal gut microbiota modulates brain development and behavior. Proc Natl Acad Sci USA 108(7):3047–3052. doi:10.1073/pnas.1010529108

    Article  PubMed  Google Scholar 

  • Do TT, Hindlet P, Waligora-Dupriet AJ, Kapel N, Neveux N, Mignon V, Delomenie C, Farinotti R, Feve B, Buyse M (2014) Disturbed intestinal nitrogen homeostasis in a mouse model of high-fat diet-induced obesity and glucose intolerance. Am J Physiol Endocrinol Metab 306(6):E668–E680. doi:10.1152/ajpendo.00437.2013

    Article  CAS  PubMed  Google Scholar 

  • Duncan SH, Belenguer A, Holtrop G, Johnstone AM, Flint HJ, Lobley GE (2007) Reduced dietary intake of carbohydrates by obese subjects results in decreased concentrations of butyrate and butyrate-producing bacteria in feces. Appl Environ Microbiol 73(4):1073–1078. doi:10.1128/AEM.02340-06

    Article  CAS  PubMed  Google Scholar 

  • Evenepoel P, Claus D, Geypens B, Hiele M, Geboes K, Rutgeerts P, Ghoos Y (1999) Amount and fate of egg protein escaping assimilation in the small intestine of humans. Am J Physiol 277(5 Pt 1):G935–G943

    CAS  PubMed  Google Scholar 

  • Gill SR, Pop M, Deboy RT, Eckburg PB, Turnbaugh PJ, Samuel BS, Gordon JI, Relman DA, Fraser-Liggett CM, Nelson KE (2006) Metagenomic analysis of the human distal gut microbiome. Science 312(5778):1355–1359. doi:10.1126/science.1124234

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Greenblum S, Turnbaugh PJ, Borenstein E (2012) Metagenomic systems biology of the human gut microbiome reveals topological shifts associated with obesity and inflammatory bowel disease. Proc Natl Acad Sci USA 109(2):594–599. doi:10.1073/pnas.1116053109

    Article  CAS  PubMed  Google Scholar 

  • Han GG, Lee JY, Jin GD, Park J, Choi YH, Chae BJ, Kim EB, Choi YJ (2017) Evaluating the association between body weight and the intestinal microbiota of weaned piglets via 16S rRNA sequencing. Appl Microbiol Biotechnol 101(14):5903–5911. doi:10.1007/s00253-017-8304-7

    Article  CAS  PubMed  Google Scholar 

  • Haro C, Garcia-Carpintero S, Alcala-Diaz JF, Gomez-Delgado F, Delgado-Lista J, Perez-Martinez P, Rangel Zuniga OA, Quintana-Navarro GM, Landa BB, Clemente JC, Lopez-Miranda J, Camargo A, Perez-Jimenez F (2016) The gut microbial community in metabolic syndrome patients is modified by diet. J Nutr Biochem 27:27–31. doi:10.1016/j.jnutbio.2015.08.011

    Article  CAS  PubMed  Google Scholar 

  • Hijova E, Chmelarova A (2007) Short chain fatty acids and colonic health. Bratisl Lek Listy 108(8):354–358

    CAS  PubMed  Google Scholar 

  • Hisamatsu T, Okamoto S, Hashimoto M, Muramatsu T, Andou A, Uo M, Kitazume MT, Matsuoka K, Yajima T, Inoue N, Kanai T, Ogata H, Iwao Y, Yamakado M, Sakai R, Ono N, Ando T, Suzuki M, Hibi T (2012) Novel, objective, multivariate biomarkers composed of plasma amino acid profiles for the diagnosis and assessment of inflammatory bowel disease. PLoS One 7(1):e31131. doi:10.1371/journal.pone.0031131

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Hullar MAJ, Fu BC (2014) Diet, the gut microbiome, and epigenetics. Cancer J 20(3):170–175

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Human Microbiome Project C (2012) Structure, function and diversity of the healthy human microbiome. Nature 486(7402):207–214. doi:10.1038/nature11234

    Article  Google Scholar 

  • Jost T, Lacroix C, Braegger C, Chassard C (2014) Stability of the maternal gut microbiota during late pregnancy and early lactation. Curr Microbiol 68(4):419–427. doi:10.1007/s00284-013-0491-6

    Article  CAS  PubMed  Google Scholar 

  • Karlsson FH, Tremaroli V, Nookaew I, Bergstrom G, Behre CJ, Fagerberg B, Nielsen J, Backhed F (2013) Gut metagenome in European women with normal, impaired and diabetic glucose control. Nature 498(7452):99–103. doi:10.1038/nature12198

    Article  CAS  PubMed  Google Scholar 

  • Keightley PC, Koloski NA, Talley NJ (2015) Pathways in gut-brain communication: evidence for distinct gut-to-brain and brain-to-gut syndromes. Aust NZ J Psychiatry 49(3):207–214. doi:10.1177/0004867415569801

    Article  Google Scholar 

  • Klose V, Bayer K, Bruckbeck R, Schatzmayr G, Loibner AP (2010) In vitro antagonistic activities of animal intestinal strains against swine-associated pathogens. Vet Microbiol 144(3–4):515–521. doi:10.1016/j.vetmic.2010.02.025

    Article  PubMed  Google Scholar 

  • Koren O, Goodrich JK, Cullender TC, Spor A, Laitinen K, Backhed HK, Gonzalez A, Werner JJ, Angenent LT, Knight R, Backhed F, Isolauri E, Salminen S, Ley RE (2012) Host remodeling of the gut microbiome and metabolic changes during pregnancy. Cell 150(3):470–480. doi:10.1016/j.cell.2012.07.008

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Ley RE (2010) Obesity and the human microbiome. Curr Opin Gastroenterol 26(1):5–11. doi:10.1097/MOG.0b013e328333d751

    Article  PubMed  Google Scholar 

  • Ley RE, Turnbaugh PJ, Klein S, Gordon JI (2006) Microbial ecology: human gut microbes associated with obesity. Nature 444(7122):1022–1023. doi:10.1038/4441022a

    Article  CAS  PubMed  Google Scholar 

  • Macfarlane GT, Macfarlane S (2012) Bacteria, colonic fermentation, and gastrointestinal health. J AOAC Int 95(1):50–60

    Article  CAS  PubMed  Google Scholar 

  • Maes M, Rief W (2012) Diagnostic classifications in depression and somatization should include biomarkers, such as disorders in the tryptophan catabolite (TRYCAT) pathway. Psychiatry Res 196(2–3):243–249. doi:10.1016/j.psychres.2011.09.029

    Article  CAS  PubMed  Google Scholar 

  • Maes M, Mihaylova I, Ruyter MD, Kubera M, Bosmans E (2007) The immune effects of TRYCATs (tryptophan catabolites along the IDO pathway): relevance for depression—and other conditions characterized by tryptophan depletion induced by inflammation. Neuro Endocrinol Lett 28(6):826–831

    CAS  PubMed  Google Scholar 

  • Maes M, Leonard BE, Myint AM, Kubera M, Verkerk R (2011) The new ‘5-HT’ hypothesis of depression: cell-mediated immune activation induces indoleamine 2,3-dioxygenase, which leads to lower plasma tryptophan and an increased synthesis of detrimental tryptophan catabolites (TRYCATs), both of which contribute to the onset of depression. Prog Neuropsychopharmacol Biol Psychiatry 35(3):702–721. doi:10.1016/j.pnpbp.2010.12.017

    Article  CAS  PubMed  Google Scholar 

  • Mardinoglu A, Shoaie S, Bergentall M, Ghaffari P, Zhang C, Larsson E, Backhed F, Nielsen J (2015) The gut microbiota modulates host amino acid and glutathione metabolism in mice. Mol Syst Biol 11(10):834. doi:10.15252/msb.20156487

    Article  PubMed  PubMed Central  Google Scholar 

  • Mawe GM, Hoffman JM (2013) Serotonin signalling in the gut—functions, dysfunctions and therapeutic targets. Nat Rev Gastroenterol Hepatol 10(8):473–486. doi:10.1038/nrgastro.2013.105

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Mazloom Z, Yousefinejad A, Dabbaghmanesh MH (2013) Effect of probiotics on lipid profile, glycemic control, insulin action, oxidative stress, and inflammatory markers in patients with type 2 diabetes: a clinical trial. Iran J Med Sci 38(1):38–43

    PubMed  PubMed Central  Google Scholar 

  • Metges CC, El-Khoury AE, Henneman L, Petzke KJ, Grant I, Bedri S, Pereira PP, Ajami AM, Fuller MF, Young VR (1999) Availability of intestinal microbial lysine for whole body lysine homeostasis in human subjects. Am J Physiol 277(4 Pt 1):E597–E607

    CAS  PubMed  Google Scholar 

  • Morris G, Berk M, Carvalho A, Caso JR, Sanz Y, Walder K, Maes M (2016) The role of the microbial metabolites including tryptophan catabolites and short chain fatty acids in the pathophysiology of immune-inflammatory and neuroimmune disease. Mol Neurobiol. doi:10.1007/s12035-016-0004-2

    Google Scholar 

  • Mu CL, Yang YX, Yu KF, Yu M, Zhang CJ, Su Y, Zhu WY (2017) Alteration of metabolomic markers of amino-acid metabolism in piglets with in-feed antibiotics. Amino Acids 49(4):771–781. doi:10.1007/s00726-017-2379-4

    Article  CAS  PubMed  Google Scholar 

  • Neis EP, Dejong CH, Rensen SS (2015) The role of microbial amino acid metabolism in host metabolism. Nutrients 7(4):2930–2946. doi:10.3390/nu7042930

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Nguyen NT, Nakahama T, Le DH, Van Son L, Chu HH, Kishimoto T (2014) Aryl hydrocarbon receptor and kynurenine: recent advances in autoimmune disease research. Front Immunol 5:551. doi:10.3389/fimmu.2014.00551

    Article  PubMed  PubMed Central  Google Scholar 

  • O’Mahony SM, Clarke G, Borre YE, Dinan TG, Cryan JF (2015) Serotonin, tryptophan metabolism and the brain-gut-microbiome axis. Behav Brain Res 277:32–48. doi:10.1016/j.bbr.2014.07.027

    Article  PubMed  Google Scholar 

  • Partanen KH, Mroz Z (1999) Organic acids for performance enhancement in pig diets. Nutr Res Rev 12(1):117–145. doi:10.1079/095442299108728884

    Article  CAS  PubMed  Google Scholar 

  • Qin J, Li R, Raes J, Arumugam M, Burgdorf KS, Manichanh C, Nielsen T, Pons N, Levenez F, Yamada T, Mende DR, Li J, Xu J, Li S, Li D, Cao J, Wang B, Liang H, Zheng H, Xie Y, Tap J, Lepage P, Bertalan M, Batto JM, Hansen T, Le Paslier D, Linneberg A, Nielsen HB, Pelletier E, Renault P, Sicheritz-Ponten T, Turner K, Zhu H, Yu C, Li S, Jian M, Zhou Y, Li Y, Zhang X, Li S, Qin N, Yang H, Wang J, Brunak S, Dore J, Guarner F, Kristiansen K, Pedersen O, Parkhill J, Weissenbach J, Meta HITC, Bork P, Ehrlich SD, Wang J (2010) A human gut microbial gene catalogue established by metagenomic sequencing. Nature 464(7285):59–65. doi:10.1038/nature08821

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Qin J, Li Y, Cai Z, Li S, Zhu J, Zhang F, Liang S, Zhang W, Guan Y, Shen D, Peng Y, Zhang D, Jie Z, Wu W, Qin Y, Xue W, Li J, Han L, Lu D, Wu P, Dai Y, Sun X, Li Z, Tang A, Zhong S, Li X, Chen W, Xu R, Wang M, Feng Q, Gong M, Yu J, Zhang Y, Zhang M, Hansen T, Sanchez G, Raes J, Falony G, Okuda S, Almeida M, LeChatelier E, Renault P, Pons N, Batto JM, Zhang Z, Chen H, Yang R, Zheng W, Li S, Yang H, Wang J, Ehrlich SD, Nielsen R, Pedersen O, Kristiansen K, Wang J (2012) A metagenome-wide association study of gut microbiota in type 2 diabetes. Nature 490(7418):55–60. doi:10.1038/nature11450

    Article  CAS  PubMed  Google Scholar 

  • Rist VT, Weiss E, Eklund M, Mosenthin R (2013) Impact of dietary protein on microbiota composition and activity in the gastrointestinal tract of piglets in relation to gut health: a review. Anim Int J Anim Biosci 7(7):1067–1078. doi:10.1017/S1751731113000062

    Article  CAS  Google Scholar 

  • Santacruz A, Collado MC, Garcia-Valdes L, Segura MT, Martin-Lagos JA, Anjos T, Marti-Romero M, Lopez RM, Florido J, Campoy C, Sanz Y (2010) Gut microbiota composition is associated with body weight, weight gain and biochemical parameters in pregnant women. Br J Nutr 104(1):83–92. doi:10.1017/S0007114510000176

    Article  CAS  PubMed  Google Scholar 

  • Sato N, Moore FA, Kone BC, Zou L, Smith MA, Childs MA, Moore-Olufemi S, Schultz SG, Kozar RA (2006) Differential induction of PPAR-gamma by luminal glutamine and iNOS by luminal arginine in the rodent postischemic small bowel. Am J Physiol Gastrointest Liver Physiol 290(4):G616–G623. doi:10.1152/ajpgi.00248.2005

    Article  CAS  PubMed  Google Scholar 

  • Schicho R, Nazyrova A, Shaykhutdinov R, Duggan G, Vogel HJ, Storr M (2010) Quantitative metabolomic profiling of serum and urine in DSS-induced ulcerative colitis of mice by (1)H NMR spectroscopy. J Proteome Res 9(12):6265–6273. doi:10.1021/pr100547y

    Article  CAS  PubMed  Google Scholar 

  • Shen Q, Chen YA, Tuohy KM (2010) A comparative in vitro investigation into the effects of cooked meats on the human faecal microbiota. Anaerobe 16(6):572–577. doi:10.1016/j.anaerobe.2010.09.007

    Article  CAS  PubMed  Google Scholar 

  • Sridharan GV, Choi K, Klemashevich C, Wu C, Prabakaran D, Pan LB, Steinmeyer S, Mueller C, Yousofshahi M, Alaniz RC, Lee K, Jayaraman A (2014) Prediction and quantification of bioactive microbiota metabolites in the mouse gut. Nat Commun 5:5492. doi:10.1038/ncomms6492

    Article  CAS  PubMed  Google Scholar 

  • Stone TW, Stoy N, Darlington LG (2013) An expanding range of targets for kynurenine metabolites of tryptophan. Trends Pharmacol Sci 34(2):136–143. doi:10.1016/j.tips.2012.09.006

    Article  CAS  PubMed  Google Scholar 

  • Tilg H, Kaser A (2011) Gut microbiome, obesity, and metabolic dysfunction. J Clin Investig 121(6):2126–2132. doi:10.1172/JCI58109

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Tremaroli V, Backhed F (2012) Functional interactions between the gut microbiota and host metabolism. Nature 489(7415):242–249. doi:10.1038/nature11552

    Article  CAS  PubMed  Google Scholar 

  • Tremblay F, Krebs M, Dombrowski L, Brehm A, Bernroider E, Roth E, Nowotny P, Waldhausl W, Marette A, Roden M (2005) Overactivation of S6 kinase 1 as a cause of human insulin resistance during increased amino acid availability. Diabetes 54(9):2674–2684

    Article  CAS  PubMed  Google Scholar 

  • Turnbaugh PJ, Hamady M, Yatsunenko T, Cantarel BL, Duncan A, Ley RE, Sogin ML, Jones WJ, Roe BA, Affourtit JP, Egholm M, Henrissat B, Heath AC, Knight R, Gordon JI (2009) A core gut microbiome in obese and lean twins. Nature 457(7228):480–484. doi:10.1038/nature07540

    Article  CAS  PubMed  Google Scholar 

  • Uronis JM, Muhlbauer M, Herfarth HH, Rubinas TC, Jones GS, Jobin C (2009) Modulation of the intestinal microbiota alters colitis-associated colorectal cancer susceptibility. PLoS One 4(6):e6026. doi:10.1371/journal.pone.0006026

    Article  PubMed  PubMed Central  Google Scholar 

  • Vijay-Kumar M, Aitken JD, Carvalho FA, Cullender TC, Mwangi S, Srinivasan S, Sitaraman SV, Knight R, Ley RE, Gewirtz AT (2010) Metabolic syndrome and altered gut microbiota in mice lacking Toll-like receptor 5. Science 328(5975):228–231. doi:10.1126/science.1179721

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Vital M, Howe AC, Tiedje JM (2014) Revealing the bacterial butyrate synthesis pathways by analyzing (meta) genomic data. MBio. doi:10.1128/mBio.00889-14

    PubMed  PubMed Central  Google Scholar 

  • Vrieze A, Van Nood E, Holleman F, Salojarvi J, Kootte RS, Bartelsman JF, Dallinga-Thie GM, Ackermans MT, Serlie MJ, Oozeer R, Derrien M, Druesne A, Van Hylckama Vlieg JE, Bloks VW, Groen AK, Heilig HG, Zoetendal EG, Stroes ES, de Vos WM, Hoekstra JB, Nieuwdorp M (2012) Transfer of intestinal microbiota from lean donors increases insulin sensitivity in individuals with metabolic syndrome. Gastroenterology 143(4):913–916 e917. doi:10.1053/j.gastro.2012.06.031

  • Wang TJ, Larson MG, Vasan RS, Cheng S, Rhee EP, McCabe E, Lewis GD, Fox CS, Jacques PF, Fernandez C, O’Donnell CJ, Carr SA, Mootha VK, Florez JC, Souza A, Melander O, Clish CB, Gerszten RE (2011) Metabolite profiles and the risk of developing diabetes. Nat Med 17(4):448–453. doi:10.1038/nm.2307

    Article  PubMed  PubMed Central  Google Scholar 

  • Wong JM, de Souza R, Kendall CW, Emam A, Jenkins DJ (2006) Colonic health: fermentation and short chain fatty acids. J Clin Gastroenterol 40(3):235–243

    Article  CAS  PubMed  Google Scholar 

  • Wu G (2013) Functional amino acids in nutrition and health. Amino Acids 45(3):407–411. doi:10.1007/s00726-013-1500-6

    Article  CAS  PubMed  Google Scholar 

  • Wu G, Bazer FW, Dai Z, Li D, Wang J, Wu Z (2014) Amino acid nutrition in animals: protein synthesis and beyond. Annu Rev Anim Biosci 2:387–417. doi:10.1146/annurev-animal-022513-114113

    Article  CAS  PubMed  Google Scholar 

  • Zhang LM, Nichols RG, Correll J, Murray IA, Tanaka N, Smith PB, Hubbard TD, Sebastian A, Albert I, Hatzakis E, Gonzalez FJ, Perdew GH, Patterson AD (2015) Persistent organic pollutants modify gut microbiota-host metabolic homeostasis in mice through aryl hydrocarbon receptor activation. Environ Health Perspect 123(7):679–688. doi:10.1289/ehp.1409055

    PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

This work was supported by National Natural Science Foundation of China (no. 81600509).

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Rui Lin.

Ethics declarations

Conflict of interest

The author declares that there is no conflict of interest regarding the publication of this article.

Ethical statements

This review does not involve any human participants and animal work.

Additional information

Handling Editors: C.-A. A. Hu, Y. Yin, Y. Hou, G. Wu, Y. Teng.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Lin, R., Liu, W., Piao, M. et al. A review of the relationship between the gut microbiota and amino acid metabolism. Amino Acids 49, 2083–2090 (2017). https://doi.org/10.1007/s00726-017-2493-3

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00726-017-2493-3

Keywords

Navigation