Glycine and serine are both non-essential amino acids that can be synthesized in the body. Glycine is the smallest amino acid and is important for muscle tissue, central nervous system function, and collagen formation. Serine participates in biosynthesis of other amino acids and metabolites and has structural and signaling roles in enzymes and neurotransmitters. Both amino acids share metabolic pathways and deficiencies can impact growth and development. Studies show glycine and serine may help with sleep, fight cancer cell growth, and reduce osteoarthritis symptoms.

1. GLYCINE AMINO ACID
Dr. Mohammed Ellulu

2. What is the Glycine?
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 Glycine is the smallest amino acids.
 Chemical formula is (NH2CH2COOH).
 Chemical structure:
 Colourless, sweet-tasting crystalline, hydrophilic or
hydrophobic; due to its side chain is only one
hydrogen atom.

3. Biosynthesis
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 Glycine is non-essential A.A.
 Biosynthesized in the body from the A.A. Serine,
which is in turn derived from 3-phosphoglycerate.
 The enzyme Serine hydroxymethyltransferase
catalyses this transformation via the cofactor
pyridoxal phosphate:
 Serine + tetrahydrofolate → Glycine + N5,N10-
Methylene tetrahydrofolate + H2O

4. Biosynthesis in liver
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 Catalyzed by glycine synthase (glycine cleavage
enzyme), to get a reversible conversion.
 CO2 + NH4+ + N5,N10-Methylene tetrahydrofolate +
NADH + H+→ Glycine + tetrahydrofolate + NAD+
 Most proteins incorporate only small quantities of
glycine.
 A notable exception is collagen, which contains
about 35% glycine.

5. Absorption of Amino Acids
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 Conceptually identical to monosaccharides.
 Luminal plasma membrane bears sodium-
dependent amino acid transporters.
 Depends on the electrochemical gradient of
sodium across the epithelium.
 Absorption of di/tripeptides in small intestinal
epithelial cell by cotransport with H+ ions.

6. Metabolism and
degradation
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7. Physiological actions of Glycine
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 Create muscle tissue.
 Maintaining healthy central nervous and digestive
systems.
 Provide protection via antioxidants from some types of
cancer.
 Almost 1/3 of collagen, which keeps the skin and
connective tissue firm and flexible.
 Glucogenic: supply body with glucose needed for
energy.
 Help reduce the symptoms of prostatic hyperplasia in
men.

8. 8 Studies about Glycine

9. Amino acid promotes sleep (Ajinomoto,2004)
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 A study of the brains of rats revealed that glycine
accumulates in the pineal gland, a part of the brain
associated with the rhythms of waking and sleeping.
 3g of glycine has tested on a group of men with
sleep problems. Taking the supplement within an
hour before going to bed.
 The researchers said the subjects showed brainwave
patterns associated with non-REM sleep sooner and
slept longer than those who did not take the amino
acid.

10. Cancer Addicted to Glycine (Jain et al, 2012)
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 According to study, the amino acid glycine fuels
fast-growing cancer cells.
 Glycine is consumed by cancer cells but is released
by normal cells.
 Food diaries from 60 human cancer cell lines show
that they all consume large amounts of the amino
acid glycine when growing fast.
 The team used liquid chromatography coupled with
mass spectrometry.

11. Collagen for Osteoarthritis (world congress, 2003)
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 Joint diseases account for the majority of all chronic conditions in
people aged 65 and older and osteoarthritis represents the single
most prevalent age-related disease.
 Dr Hans-Konrad Selbmann, from the German University in
Tuebingen, highlighted a study within 1991:
 Adam et al compared four treatments to reduce the patients' levels
of pain:
1- collagen hydrolysate.
2- gelatine.
3- gelatine-glycine-calcium-fluid combination.
4- albumin proteins.
 The study found that all three of the gelatine treatments were
effective and significantly superior to the protein supplementation.

12. women's health (AHPA, 2005)
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 New information on botanicals from American
Herbal Products Association such as”
 red clover (Trifolium pratense) used for menopause,
 Chaste tree (Vitex agnus-castus) used to ease PMS,
 and soy (Glycine max), which is considered by some
as an alternative to hormone replacement therapy.

13. Anti-carcinogenic factors
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 Vitiva CEO, a special neutraceutical company in
Slovenia, studied the rosemary-derived anti-
oxidants, and yeast powder for the reduction of
acrylamide in fried foods.
 Acrylamide is a carcinogen discovered by Swedish
scientists in 2002.
 Yeast contains almost: L-cysteine, glycine and L-
lysine.

14. References
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 Ajinomoto Company (2004). Japanese amino acids supplier
Ajinomoto is considering commercializing food supplements
containing glycine, based on studies showing the amino acid could
help people sleep better. William Reed Business Media SAS.
NutraIngredients publications.
 Jain M, et al (2012). Metabolite profiling identifies a key role for
glycine in rapid cancer cell proliferation. Science 336:1040-1044.
 The 8th world congress of the Osteoarthritis Research Society
International took place in Berlin from 12-15 October 2003.
 American Herbal Products Association (2005). The first International
Symposium on the Role of Botanicals in Women's Health. The
symposium will take place on 16 & 17 February at Rutgers
University in New Brunswick, New Jersey.

15. SERINE AMINO ACID

16. What is Serine?
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 Chemical formula HO2CCH(NH2)CH2OH.
 Chemical structure:
 One of the proteinogenic amino acids.
 By hydroxyl group, serine is classified as a polar
amino acid.

17. Biosynthesis
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 The biosynthesis of serine starts with the oxidation
of 3-phosphoglycerate to 3-phosphohydroxy-
pyruvate and NADH.
 Reductive amination of this ketone followed by
hydrolysis gives serine.
 Serine hydroxymethyltransferase catalyzes
conversions of L-serine to glycine and 5,6,7,8-
tetrahydrofolate to 5,10-methylenetetrahydrofolate

18. Biosynthesis
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19. Serine deficiency
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 Serine deficiency is a rare, inherited, metabolic
disorder that interferes with normal growth and
development, particularly in the central nervous
system.
 Unlike similar neurodevelopmental disorders, serine
deficiency can be treated.
 Children with serine deficiency are born with an
abnormally small head (called microcephaly).

20. Biological functions
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Metabolic
 participates in the biosynthesis of purines and
pyrimidines.
 precursor to several amino acids including glycine
and cysteine.
 precursor to numerous metabolites, including folate,
which is the principal donor of one-carbon
fragments in biosynthesis.

21. Biological functions
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Structural role
 catalytic function of many enzymes.
 occur in the active sites of chymotrypsin, trypsin.
 nerve gases and insecticides shown to act by
combining with a residue of serine in the active site
of acetylcholine esterase.
 Serine proteases are a common type of protease.

22. Biological functions
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Signalling
 D-Serine, synthesized in the brain by serine
racemase from L-serine serves as a neurotransmitter.
 D-serine is a potent agonist at the glycine site of the
NMDA-type glutamate receptor. For the receptor to
open, glutamate and either glycine or D-serine must
bind to it.
 D-serine is a more potent agonist at the glycine site
on the NMDAR than glycine itself.

23. Biological functions
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Gustatory sensation
 Pure D-Serine is an off-white crystalline powder
with dirty aroma.
 L-Serine is sweet with sour tastes at high
concentration.
 D-Serine is sweet with an additional minor sour
taste at medium and high concentrations.

24. Glycine and Serine amino acids share in
metabolism pathway
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25. 25 Studies about Serine

26. Cheese protect against IBD (Sprong et al, 2009)
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 The study, published in the Journal of Dairy Science,
suggests that dietary cheese whey protein could
reduce symptoms and markers of inflammatory
bowel disease (IBD), after it was found to reduce
gene expression of inflammation markers and
diminish the clinical symptoms of IBD such as
diarrhea and fecal blood loss in an animal model.
 The study recommended that whey protein rich in:
threonine, serine ,cysteine.

27. Soy and Casein decrease muscle
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protein breakdown (Luiking et al, 2010)
 The study involved 22 healthy 22 year olds
randomly assigned to receive moderate-nitrogen
and carbohydrate casein and soy meals.
 Researchers from the University of Arkansas for
Medical Sciences, Maastricht University….US.
 The synthesis of muscle protein between the groups,
did not suggest differences in changes in soy and
casein, as they were rich in glutamate, glutamine,
serine, histidine, isoleucine and branched chain
amino acids.

28. Energy abounds in soft drinks market
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 Energy drinks in the UK the Jordan Grand Prix
brand has jumped on the bandwagon with the
creation of the EJ-10 Liquid Performance Drink,
named after Jordan Grand Prix's founder Eddie
Jordan and the 10 active ingredients in the drink.
 Jordan EJ-10 is a hypotonic drink targeting drivers.
 It contains phosphatidyl serine, maltodextrins and
isolated proteins, but no caffeine or taurine.
Mintel's Global New Products Database: www.gnpd.com

29. Chemi Nutraceuticals
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 Chemi Nutraceuticals is the new US branch of
parent company C hemi, a privately held
pharmaceutical and nutraceutical company based in
Milan, Italy.
 Chemi, with cGMP certified manufacturing facilities
in Italy and Brazil, is best known in the US nutritional
arena for its introduction of phosphatidyl serine
(PS), the popular dietary supplement used to
enhance learning, memory, and concentration.

30. References
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 Sprong RC , Schonewille AJ and van der Meer R (2009). Cheese whey protein may
help to reduce genetic markers and symptoms associated with inflammatory bowel
disease, according to a new study in rats. Journal of Dairy Science. 93: 1364–
1371.
 Luiking YC, Engelen MPKJ, Soeters PB, Boirie Y and Deutz NEP (2010). Protein from
soy or casein both benefit the synthesis of muscle protein at the same rate. Clinical
Nutrition. doi: 10.1016.