Lehninger Stryer Γεωργάτσος Internet
Lehninger
Stryer
Γεωργάτσος
Internet
1800 Πέψη
κρέατος
και
αμύλου
από
βιολογικά
υγρά
στομάχου1850 Louis Pasteur Ζύμωση
σακχάρων, μήκυτες
απαραίτητοι
1897 Eduard Buchner υδρόλυμα
μηκύτων
Nobel 1907
1926 James Sumner καθαρισμός
ουρεάσης1930 John Northop
& Stanley κρυστάλλωσαν
pepsin & trypsin
Nobel 1946Σήμερα
πάνω
από
2000 ένζυμα
καλά
χαρακτηρισμένα
Τρισδιάστατη
δομήπρωτεϊνών
Ηλεκτρονική
πυκνότητα
Χάρτης
αντανάκλασης
Κρυσταλλογράφος
ΕΝΖΥΜΑΚΑΤΑΤΑΞΗ
ΚΑΙ
ΟΝΟΜΑΣΙΑ
ΤΩΝ
ΕΝΖΥΜΩΝ
1.
Οξειδορεδουκτάσες2.
Τρανσφεράσες
3.
Υδρολάσες4.
Λυάσες
5.
Ισομεράσες6.
Λιγάσες
Φωσφουδρολάση
ορθοφωσφορικών
μονοεστέρωνΑλκαλική
φωσφατάση
(κοινή
ονομασία)
3.1.3.13=υδρολάσες1=υδρολάσες
που
δρούν
σε
εστερικούς
δεσμούς
3= υποομάδα
που
δρα
σε
φωσφορικούς
μονοεστέρες1= ειδικό
ένζυμο
υποομάδας
3.1.3.2= όξινη
φωσφατάση
EC 1OxidoreductasesEC 1.1
Acting on the CH-OH group of donorsEC1.2
Acting on the aldehyde or oxo
group of donorsEC 1.3
Acting on the CH-CH group of donorsEC 1.4
Acting on the CH-NH2
group of donorsEC 1.5
Acting on the CH-NH group of donorsEC 1.6
Acting on NADH or NADPHEC 1.7
Acting on other nitrogenous compounds as donorsEC 1.8
Acting on a sulfur group of donorsEC 1.9
Acting on a heme group of donorsEC 1.10
Acting on diphenols
and related substances as donorsEC 1.11
Acting on a peroxide as acceptorEC 1.12
Acting on hydrogen as donorEC 1.13
Acting on single donors with incorporation of molecular oxygen (oxygenases)EC 1.14
Acting on paired donors, with incorporation or reduction of molecular oxygenEC 1.15
Acting on superoxide
radicals as acceptorEC 1.16
Oxidising metal ionsEC 1.17
Acting on CH or CH2
groupsEC 1.18
Acting on iron-sulfur proteins as donorsEC 1.19
Acting on reduced flavodoxin
as donorEC 1.20
Acting on phosphorus or arsenic in donorsEC 1.21
Acting on X-H and Y-H to form an X-Y bondEC 1.97
Other oxidoreductases
EC 2TransferasesEC 2.1Transferring one-carbon groupsEC 2.2Transferring aldehyde or ketonic
groupsEC 2.3AcyltransferasesEC 2.4GlycosyltransferasesEC 2.5Transferring alkyl or aryl groups, other than methyl groupsEC 2.6Transferring nitrogenous groupsEC 2.7Transferring phosphorus-containing groupsEC 2.8Transferring sulfur-containing groupsEC 2.9Transferring selenium-containing groupsEC 3HydrolasesEC 3.1
Acting on ester bondsEC 3.2GlycosylasesEC 3.3Acting on ether bondsEC 3.4Acting on peptide bonds (peptidases)EC 3.5Acting on carbon-nitrogen bonds, other than peptide bondsEC 3.6Acting on acid anhydridesEC 3.7Acting on carbon-carbon bondsEC 3.8Acting on halide bondsEC 3.9Acting on phosphorus-nitrogen bondsEC 3.10Acting on sulfur-nitrogen bondsEC 3.11Acting on carbon-phosphorus bondsEC 3.12Acting on sulfur-sulfur bondsEC 3.13Acting on carbon-sulfur bonds
EC 4LyasesEC 4.1Carbon-carbon lyasesEC 4.2Carbon-oxygen lyasesEC 4.3
Carbon-nitrogen lyasesEC 4.4
Carbon-sulfur lyasesEC 4.5
Carbon-halide lyasesEC 4.6
Phosphorus-oxygen lyasesEC 4.99
Other lyasesEC 5IsomerasesEC 5.1
Racemases
and epimerasesEC 5.2
cis-trans-IsomerasesEC 5.3
Intramolecular isomerasesEC 5.4
Intramolecular transferases
(mutases)EC 5.5
Intramolecular lyasesEC 5.99
Other isomerasesEC 6LigasesEC 6.1
Forming carbon—oxygen bondsEC 6.2
Forming carbon—sulfur bondsEC 6.3
Forming carbon—nitrogen bondsEC 6.4
Forming carbon—carbon
bondsEC 6.5
Forming phosphoric ester bondsEC 6.6
Forming nitrogen—metal bonds
ΟξειδορεδουκτάσεςOxidoreductase
is an enzyme
that catalyzes the transfer of electrons
from one molecule (the
reductant, also called the hydrogen acceptor or electron donor) to another (the oxidant, also called the hydrogen donor or electron acceptor). For exampleA–
+ B → A + B–
In this example, A is the reductant
(electron donor) and B is the oxidant (electron acceptor).δευδρογονάσες
καταλύουν
την
μεταφορά
υδρογόνου,
δότες
υδρογόνου
CHOH,
CHO, CHO-CH, CH-NH2, CH-NH κλπδέκτες
NAD, NADP
οξειδάσες
εάν
ο
αποδέκτης
είναι
μοριακό
οξυγόνουπεροξειδάσες
χρησιμοποιούν
το
Η2
Ο2
ως
οξειδωτικό
παράγονταυδροξυλάσες
στο
υπόστρωμα
τους
άτομα
οξυγόνου
από
μοριακό
οξυγόνο
οξυγονάσες
ενσωματώνουν
ολόκληρο
μόριο
οξυγόνου
σε
διπλούς
δεσμούς
ΤρανσφεράσεςΤransferase
is an
enzyme that catalyzes the transfer of a functional group (e.g. a
methyl or
phosphate group) from one molecule (called the donor) to another
(called the acceptor). For example, an enzyme that catalyzed this reaction would be a transferase: A–X + B → A + B–X In this example, A would be the donor, and B would be the acceptor. The donor is often a coenzymeΈνζυμα
που
μεταφέρουν
μονοανθρακικές
ομάδες, ακυλομάδες, γλυκοσυλομάδες, αζωτούχες,
φωσφορικές, θειούχες
κλπ
ΥδρολάσεςHydrolase
is an enzyme that catalyzes the hydrolysis
of a chemical bond. For example, an
enzyme that catalyzed the following reaction is a hydrolase: A–B + H2O → A–OH + B–H Διασπούν
μεγάλη
ποικιλία
δεσμών
εστεράσες, φωσφατάσες, γλυκοσιδάσες, πεπτιδάσες
Λυάσεςlyase
is an enzyme
that catalyzes the breaking of various chemical bonds
by means other than
hydrolysis
and oxidation, often forming a new double bond
or a new ring structure. For example, an enzyme that catalyzed this reaction would be a lyase: ATP
→ cAMP+ PPi
αλδολάσες
που
διασπούν
τον
δεσμό
C-C, αποκαρβοξυλάσες, κετοξυλυάσεςΙσομεράσεςisomerase
is an enzyme
that catalyses the interconversion
of polymers. Isomerases
thus catalyze
reactions of the form A → B Ρακεμάσες, επιμεράσες, cis-trans ισομεράσες
πχ
ισομεράση
της
γλυκόζης
Λιγάσεςligase
(from the Latin
verb ligāre
— "to bind" or "to glue together") is an enzyme
that can
catalyse
the joining of two large molecules by forming a new chemical bond, usually with accompanying hydrolysis
of a small chemical group pendant to one of the larger molecules.
Generally ligase
catalyses the following reaction: Ab
+ C → A–C + b or sometimesAb
+ cD
→ A–D + b + c where the lower case letters signify the small, pendant groups.
Δημιουργία
δεσμών
μεταξύ
δύο
μορίων
με
δότη
ενέργειας
ATP
Κυτοχρώματα: πρωτείνες
που
περιέχουν
αίμη, ρόλος
μεταφορά
ηλεκτρονίων, τα
πιο
γνωστά
a1
, a3
, b, c, cc1
Κυτόχρωμα
c
12400Da, 104 αμινοξέα
Δύο
δεσμοί
κυστεινών
με
τους
πυρολικούς
δακτυλίους
της
αίμης
Ι
και
ΙΙ
Αποένζυμο, ολοένζυμο, συνένζυμα
συνδέονται
στοιχειομετρικά
με
τοαποένζυμο
και
το
υπόστρωμα. Οι
βιταμίνες
εξωγενείς
διαιτητικοί
παράγοντες
Συνένζυμα
οξειδορεδουκτασών: νουκλεοτίδια
του
νικοτιναμιδίου
ΔΗ2
+ NAD+
Δ+NADH+ H+
όπου
ΔΗ2 δότης
υδρογόνου, κύριος
ρόλος
η
μεταφορά
υδρογόνου
στην
αναπνευστική
αλυσίδα
NAD+NADPΒιταμίνηνικοτιναμίδιο
Nicotinamide
adenine dinucleotide
(NAD+) is an important coenzyme
found in cells. It plays key biochemical roles as a carrier of electrons and a participant in metabolic redox
reactions, as well as in cel
signaling.
There are two forms of this coenzyme in
cells, NAD+
and the phosphorylated
form NADP+. These two related coenzymes
have
similar chemistry, but perform different roles in metabolism.
Φλαβινοσυνένζυμα
= ριβοφλαβίνη, η
αναγωγή
των
συνενζύμων
λαμβάνει
χώραμε
την
προσθήκη
υδρογόνου
στα
άτομα
Ν
*
Riboflavin (E101), also known as vitamin B2, is an easily absorbed micronutrient
with a key role in maintaining health
in animals. It is the central component of the
cofactors
FAD
and FMN, and
is therefore required by all flavoproteins. As such, vitamin B2 is required for a wide variety of cellular processes.
Like the other B
vitamins
it plays a key role in energy metabolism, and is required for the metabolism of fats, carbohydrates, and proteins.
Milk, cheese, leafy
green vegetables, liver, legumes such as mature soybeans, yeast and almonds
are good sources of vitamin B2, but exposure to light destroys riboflavin.
Άλλα
οξειδοαναγωγικά
συνένζυμα
Αίμη, ουβικινόνη
A heme
or haem
is a prosthetic group
that consists of an iron
atom contained in the center of a large heterocyclic
organic ring called a porphyrin. Not all porphyrins
contain iron, but a substantial fraction of porphyrin-containing metalloproteins
have heme as their prosthetic subunit; these are known as hemoproteins
This vitamin-like substance is, by nature, present in all human cells and responsible for the production of the body’s
own energy. In each human cell, food energy is converted into energy in the mitochondria
with the aid of CoQ10. Ninety-five percent of all the human body’s
energy requirements (ATP) is converted with the aid of CoQ10.
Therefore, those organs with the highest energy requirements –
such as the heart, the
lungs, and the liver –
have the highest
CoQ10 concentrations.
It is essential for aerobic life and a common dietary supplement. Dihydrolipoic
acid, the reduced
form of lipoic
acid, although it is sometimes also called "lipoic
acid."
One of the most visible roles of lipoic
acid is as a cofactor
in aerobic
metabolism, specifically the pyruvate
dehydrogenase complex. Lipoate
participates in transfer of
acyl
or methylamine
groups
Ασκορβικό
οξύ
Glutathione
(GSH) is a tripeptide. It contains an unusual peptide
linkage between the amine group
of cysteine
and the carboxyl
group of the glutamate
side chain. Glutathione, an antioxidant, protects cells from toxins such as free radicals.Thiol
groups are kept in a reduced
state within ~5 mM in animal
cells. In effect, glutathione reduces any disulfide bonds
formed within cytoplasmic
proteins
to cysteines
by acting as an electron
donor. Glutathione is found almost exclusively in its reduced form, since the enzyme which reverts it from its oxidized form (GSSG), glutathione reductase, is constitutively
active and inducible
upon oxidative
stress
The L-enantiomer
of ascorbic
acid is also known as vitamin C. The name "ascorbic" comes from its property of preventing and curing scurvy. Primates, including humans, and a few other species in all divisions of the animal kingdom, notably the guinea pig
have lost the ability to synthesize ascorbic
acid and must obtain it in their food.
Γλουταθειόνη
Συνένζυμα
τρανσφερασών: 1. Αδενοσινοτριφωσφορικό
οξύ-ATP
Adenosine 5'-triphosphate
(ATP) is a multifunctional
nucleotide
that is most important as a "molecular
currency" of intracellular energy
transfer. In this role, ATP transports chemical energy within cells
for metabolism. It is produced as an energy source during the processes of photosynthesis
and cellular respiration
and consumed by many enzymes
and a multitude of cellular processes including biosynthetic
reactions, motility
and cell division. In signal transduction
pathways, ATP is used as a substrate
by kinases
that phosphorylate
proteins
and lipids, as well as by adenylate
cyclase, which uses ATP to produce the second messenger
molecule cyclic AMP
Φωσφορυλιώνει
αλκόολεςR-OH + ATP R-O-P + ADPΦωσφορυλιώνει
την
γουανιδική
ομάδα
R-NH-C(NH)-NH2
+ ATP R-NH-C(NH)-NH-P + ATPΦωσφορυλιώνει
οργανικά
οξέα
R-COOH + ATP R-CO-P + ADP Πυροφωσφορυλιώνει
αλκόολες
R-OH + ATP R-O-P-P +AMP Φωσφορυλιώνει
νουκλεοτίδια
CMP + ATP CDP + ADP Αδενυλιώνει
οργανικά
οξέα
R-COOH + ATP R-CO-AMP + P-P Αδενυλιώνει
πρωτείνες
Protein-OH + ATP Protein-AMP + P-PΜεταφέρει
την
αδενοσίνη
R-S(CH3
) + ATP R-S(CH3
)-Adenosine + P-P + Pi
Ο
πιο
σημαντικός
ρόλος
του
η
φωσφορυλίωση
υποστρωμάτων
κινασών
2. Συνένζυμο
Α
ή
CoA
ή
CoA-SH μεταφέρει
ομάδες
οργανικών
οξέων.Αποτελείται
από
3’-5’
διφωσφορική
αδενοσίνη
και
φωσφορική
παντοθείνη.
Η
σπουδαιότερη
ένωση
του
το
ακέτυλο-συνένζυμο
Α
Acetyl-CoA
is an important molecule in metabolism, used in many biochemical reactions. Its main use is to convey the carbon
atoms
within the
acetyl
group to the Krebs Cycle
to be oxidized
for energy production.
3. Ενεργό
θειικό= δότης
θειικών
ομάδων
εστεροποίηση
φαινολών
στεροειδών
κλπ
4. Ενεργό
μεθύλιο
διαθέτει
την
μεθυλοομάδα
σε
άτομα
με
ελεύθερα
ηλεκτρονιακά ζεύγη
5. Ενεργό
φορμύλιο
ή
φολικό
οξύ
μεταφορέας
μονοανθρακικών
ομάδων
όπως-CH3
, -CH2
OH, -CHO στις
θέσεις
N5
και
N10
6. Ενεργό
καρβοξύλιο
ή
βιοτίνη
δεσμεύει
CO2
και
το
αποδίδεισε
αντιδράσεις
καρβοξυλίωσης
7. Πυροφωσφορική
θεαμίνη
ή
βιταμίνη
Β1
ή
θειαμίνη
δρα
ως
συνένζυμο
σε
αντιδράσειςμεταφοράς
αλδευδο
παραγώγων
8. Βιταμίνη
πυριδοξάλη
συμμετέχει
στην
μεταφορά
αμινομάδων
σε
τρανσαμινώσεις, σε
ρακεμιώσεις
και
σε
αποκαρβοξυλιώσεις
αμινοξέων
Συνένζυμα
Υδρολασών, Ισομερασών, Λυασών, Λιγασών
Κινητική
ενζυμικών
αντιδράσεων
E + S ES ES E + P
E + S ES E + Pk1
k2
k3
Industrial applications
Enzymes are used in the chemical industry
and other industrial applications when extremely specific catalysts are required. However, enzymes in general are limited in the number of reactions they have evolved to catalyse and also by their lack of stability in organic solvents
and at high temperatures. Consequently, protein engineering
is an active area of research and involves attempts to create new enzymes with novel properties, either through rational design or in vitro
evolution
Brewing industry Enzymes from barley are released during the mashing stage of beer production.They degrade starch and proteins to produce simple sugar, amino acids and peptides that are used by yeast for fermentation
Industrially produced barley enzymesWidely used in the brewing process to substitute for the natural
enzymes found in barley.Amylase, glucanases, proteases:Split polysaccharides and proteins in the malt.Betaglucanases
and arabinoxylanases:Improve the wort
and beer filtration characteristics.Amyloglucosidase
and pullulanases:Low-calorie beer
and adjustment of fermentability.Proteases: Remove cloudiness produced during storage of beers.Acetolactatedecarboxylase
(ALDC): avoid the formation of diacetyl
Baking industry Fungal
alpha-amylase enzymes are normally inactivated at about 50 degrees Celsius, but are destroyed during the baking process.
Catalyze breakdown of starch in the flour
to sugar. Yeast action on sugar produces carbon dioxide. Used in production of white bread, buns, and rolls.
ProteasesBiscuit manufacturers use them to lower the protein level of
flour.
Amylases, Xylanases, Cellulases
and ligninasesDegrade starch to lower viscosity, aiding sizing
and coating paper. Xylanases
reduce bleach required for decolorising; cellulases
smooth fibers, enhance water drainage, and promote ink removal; lipases reduce pitch and lignin-
degrading enzymes remove lignin
to soften paper.
Paper industry
Glucose Fructose
Amylases, amyloglucosideases
and glucoamylases:Converts starch
into glucose
and various syrupsGlucose isomerase:
Converts glucose
into fructose
in production of high fructose syrups
from starchy materials. These syrups have enhanced sweetening
properties and lower calorific values
than sucrose for the same level of sweetness
Starch industry
Dairy industryRennin
derived from the stomachs of young ruminant animals
manufacture of cheese, used to hydrolyze
proteinMicrobially
produced enzyme increasing use in the dairy industry.
Lipases
is implemented during the production of Roquefort cheese
to enhance the ripening of the blue-mould cheese.
Lactases Break down lactose
to glucose
and galactose
Papain
To soften meat for cooking
Restriction enzymes, DNA ligase
and polymerases
Used to manipulate DNA in genetic engineering, important in pharmacology, agriculture
and medicine. Essential for restriction digestion
and the polymerase chain reaction. Molecular biology is also important in forensic science.
Molecular biology
Proteases:
produced in an extracellular
form from bacteria
Used for presoak conditions and direct liquid applications helping with removal of protein stains from clothesAmylases: Detergents for machine dish washing to remove resistant starch residues.
Lipases:
Used to assist in the removal of fatty and oily stains
Cellulases:
Used in biological fabric conditioners
Cellulases:
Used to break down cellulose into sugars that can be fermented
Detergents
Biofuel
industry
One example is the most common type of phenylketonuria. A mutation of a single amino acid in the enzyme phenylalanine hydroxylase, which catalyzes the first step in the degradation of phenylalanine, results in build-up of phenylalanine and related products. This can lead to mental retardation
if the disease is untreated
Phenylalanine hydroxylase
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με
ασθένειες