chimie biologica
TRANSCRIPT
MII)(50AMINOACIZI de ulemacromolec
Fe Mg, Cu,S P,
N
O
H
C
cuaternare Subst.
STRUCTURA
CHIMICA COMPOZITIECataliz enzimatic.Transport i stocare.Micare coordonat.Suport mecanic.Imunitate.
EINEHETEROPROT
NEHOLOPROTEIPROTEINE
EPOLIPEPTID
DEOLIGOPEPTIPEPTIDE
PROTIDE
R
NH
COOH
2
CH
alaninaβexceptie
α
proteine20
aa 200
1) Clasificarea aminoacizilor din punct de vedere structural
a) Aminoacizi cu caten hidrocarbonat - Glicina (Gly)- Alanina (Ala)- Valina (Val)- Leucina (Leu)- Izoleucina (Ile)
A) AMINOACIZI ALIFATICI
1) Clasificarea aminoacizilor din punct de vedere structural1) Clasificarea aminoacizilor din punct de vedere structural
b) Aminoacizi hidroxilai
- Serina (Ser)
- Treonina (Thr)
c) Aminoacizi sulfurai
- Cisteina (Cys)
- Cistina (Cyss)
- Metionina (Met)
d) Aminoacizi dicarboxilici
- Acidul aspartic (Asp) i asparagina (Asn)
- Acidul glutamic (Glu) i glutamina (Gln)
e) Aminoacizi bazici
- Lizina (Lys)
- Arginina (Arg)
- Histidina (His)
B) AMINOACIZI CICLICI
a) Aminoacizi aromatici
- Fenilalanina (Phe)
- Tirozina (Tyr)
- Triptofan (Trp)b) Aminoacizi heterociclici
- Prolina (Pro) - Hidroxiprolina (HO-Pro)
2) Clasificarea aminoacizilor in functie de rolul biologic
a)Aminoacizi eseniali (Thr, Met, Leu, Ile, Val, Lys, Phe, Trp)
b) Aminoacizi parial eseniali (His, Arg)
c) Aminoacizi neeseniali (restul)
H COOH
NH2
CH
glicina
(acid - aminoacetic)
CH2
CH3
COOH
NH
monometil-glicina(sarcozina)
CH2COOH
N
H3C CH3 CH3
+
trimetil-glicina(betaina)
-structura gelatinei i fibroinei (25%, 40%); -compoziia acizilor biliari, glutationului,-particip la sinteza de purine i de porfirine;-participa la eliminarea nucleului benzenic sub forma de acid hipuric
ROL
(C6H5-CO-NH-CH2-COOH
Surse de grupari –CH3
H3C CH
NH2
COOH
a - alanina
(acidul -amino-propionic)
CH2
NH2
COOHCH2
- alanina
ROL
anserina
carnozinamusculare dipeptide
A coenzima
pantotenic acid
compozitia in intra
neproteic aa
CH3 CH CH COOH
CH3 NH2
valina
(acidul -amino-izovalerianic)
(aa esenial)
CH3 CH
CH3
CH2 CH COOH
NH2
leucina
(acidul -amino-izocaproic)
(aa esenial)
CH3 CH2 CH CH COOH
CH3 NH2
izoleucina
(acidul -amino--metil valerianic)
(aa esenial)
COOHCH
NH2
serina
CH2
OH
COOHCHCH2
NH2O
P O
OH
OH
fosfoserina
(acidul -amino--hidroxi-propionic)
COOHCH
NH2
CH
OH
CH3
treonina
(acidul -amino--hidroxi-butiric)
(aa esenial)
CH2 CH COOH
NH2SH
cisteina
(acidul -amino--mercapto-propionic)
CH2 CH COOH
NH2SH
cisteina
2CH2 CH COOH
NH2S
S
CH2 CH COOH
NH2
cistina
+ 2H+ + 2e-
)(CoenzimaA CISTEAMINAareDecarboxil
.biliariac TAURINAcistic ac.avansata Oxidare2CO
HS - CH2 - CH2 - NH2
Cisteamina
CH2
S
CH2 CH COOH
NH2
CH3metionina
(aa esenial)
surs de metil
(acidul -amino--metil-mercaptobutiric)
CH COOH
NH2
HOOC CH2
acid aspartic
CH COOH
NH2
CH2CO
NH2
asparagina
(acidul -amino succinic)
CH COOH
NH2
HOOC CH2 CH2
acid glutamic
(acidul -amino-glutaric)
animaleGLUTAMINA
vegetaleASPARAGINAAMINIC AZOT
aDepozitare
reaTransporta
ROL
CH COOH
NH2
OC CH2 CH2
NH2
glutamina
CH COOH
NH2
CH2 CH2CH
2NH2
lizina
abgdeCH2
(acidul ,-diamino-caproic)
CH COOH
NH2
CH CH2CH2
NH2OH
4-hidroxi-lizina
CH2
COLAGEN
GELATINAlizinaHidroxi
esential Aa.
ROL
COMPOZITIA
CH COOH
NH2
CH2 CH2CH2NHNH2
NH
Cabgd
arginina
(acidul -amino--guadin-valerianic)
PROTAMINE
HISTONEBAZICE proteine Compozitia
CUREOGENETICICLUL
esential .partial Aa
ROL
CH COOH
NH2NHN
a
histidina
CH2
b
(acidul -amino--imidazol-propionic)
(imidazol-alanina)
GLOBULINE Compozitie
ANIMALE
COPIIesential Aa.
ROL
CH COOH
NH2
aCH2
b
fenilalanina (acidul -amino--fenil-propionic)
(aa esenial)
CH COOH
NH2
aCH2
bOH
tirozina
(acidul -amino--(para-hidroxi-fenil)-propionic)
NH
CH COOH
NH2
aCH2
b
triptofan
(acidul -amino--indol-propionic) (indol-alanin)
(aa esenial)
melaninici pigmenti
inanorepinefr
epinefrina
dopamina
necatecolami
(tiroxina) tiroidieni hormoni
precursoriPhe
Tyr
zAdamkiewic
Millon
icaxantoprote
reactii apozitiveaz
280 λLUV absorbtie max.
Trp
Tyr
ROL
(acidul pirolidin-2-carboxilic)
NH
COOH
prolina
glicina) (dupa Nstr.COLAGE in tipredominan Aa.
I)SUBSTITUIT (AA. secundara aminica functia cu Aa.
ROL
NH
COOHOH
hidroxi-prolina
AMINOACIDMONOMER mic;n ulare;macromolec Subst.
glu-CO-NH-lys-CO-NH-CysPEPTIDICA leg.1002aaacondensarenat. Subst.
aa) 100(10 EPOLIPEPTIDaa) 10( DEOLIGOPEPTI
PEPTIDE
aa) (9 enonapeptideoctapeptiddeheptapeptiehexapeptiddepentapepti
aa) (4 detetrapeptiaa) (3 tripeptideaa) (2 dipeptide
Oligo
esemiciclic pept. 4)ciclice pept. 3)ramificate pept. 2)liniare pept. 1)
libere
SHOH
2NHCOOH
gr. prezenta
aminoacizidesecventa;NHCOprezenta
H2N COOHCH
R1R2
+ H2N COOH
H2O
CH
aa 1 aa 2
R3H2N
R1
CO NHCH
R2
COOHCH
H2O
H2N COOH
dipeptida
CH
H2N
R1
CO NHCH
R2
CH CO NH
R3
COOHCH
tripeptida
H2O
(n-3) aminoacizi
H2N
R1
CO NHCH CH CO NH COOHCH
RiRn
n-2
polipeptidai = 2,3......n-2
aa
)(peptidaze ENZIMATICAACIDA
A3)HIDROLIZ
HOH tesolubilita 2)AMFOTERcaracter 1)
triptofancisteinilleucilvalilalaniltirozil
trpcisleuvalalatyr
:Exemplu
aa finalcompleta denumirea il""aa de Rest
4) Reactia BIURETULUI
O = CNH2
CuSO4
2 NaOH
HN
H
N
O
NH2- NH3 O = C
O = CNH
NH2
NH2
NH
O = CNH2
NH2
C
O
C N
H
Cu
H
N
N
H
O
C
O
C
biureturee
complex cuproalcalinic (culoare violet)
-2
2 Na+
CH
NH2
HOOC CH2CH2 CO NH
CH2
CH
SH
CO NH CH2 COOH
GLUTATION
( GAMMA-glutamil-cisteinil-glicina)
H
COOH
NH2 CH
CH2
CH COOHNH2
SH
CH COOH
NH2
HOOC CH2CH2
acid glutamic
+ +
cisteina H2O2
CH
NH2
HOOC CH2CH2 CO NH
CH2
CH
SH
CO NH CH2 COOH
glutation redus( GAMMA-glutamil-cisteinil-glicina)
glicina
-legtur peptidoid
CH
NH2
HOOC CH2CH2 CO NH
CH2
CH
SH
CO NH CH2 COOH2
- 2 H+ - 2e-
glutation redus
CH
NH2
HOOC CH2CH2 CO NH
CH2
CH CO NH CH2 COOH
CH
NH2
HOOC CH2CH2 CO NH
CH2
CH
S
CO NH CH2 COOH
S
glutation oxidat
G-SH G-S-S-G2-2 H
+2 Hglutationredus
glutationoxidat
- particip la reaciile redox celulare conform reaciei
- joac rol de coenzim( donor de H):
G-SH+A 2 AH2 + G-S-S-G
ox1 red2 red1 ox2
metabolice deseuri
exenobioticedetoxifier la participa
)(OH hidroxil R.
)(O hidrogen de Peroxidul
)(O Superoxid
)O(singlet Oxigen
(RLOt antioxidan ca actioneaza
dependente SHenzime activeaza
.
22
.2
21
2
CONJUGAZASGLUTATIONenzimaticacataliza
solubili)CONJUGATI(GLUTATIONOSHG cu conjugarea
EDETOXIFIER dea aII FAZA
Nonapeptide secretate de lobul posterior al HIPOFIZEI
Vasopresina
H2N - Cys -Tyr - Phe - Gln - Asn - Cys - Pro - Arg - Gly - CONH2
S S sau Lys
Ocitocina
H2N - Cys -Tyr - Ile - Gln - Asn - Cys - Pro - Leu - Gly - CONH2
S S
1 2 3 4 5 6 7 8 9
icantidiuret
vaselor) (contr.v hipertensiaVasopresin
lactatia
uterine musc. contractiaOcitocina
Lys
ArgLeu:8 pozitia
PheIle:3 pozitia
ACTIONEAZA
STIMULAREA
INLOCUIRE
INLOCUIRE
le functionaDeosebiri
estructural Deosebiri
ticiCaracteris
rarenalacorticosup
a)biolologicfunctia a(invariabil secv.aa 24
anterioarahipofiza
STEROIZI H. DE SECRETIA STIMULA:Functia
variabila secv.aa 15aa 39:compozitie
de secretat
cys19(B)cys20(A)
cys7(B)cys7(A)B si A intre SS 2punti
bazici aaaa 30B catena
cys11)(cys6 SS 1punte
bazici aa21aaA catena
(octamer) 48000
(tetramer) 24000
(dimer) 12000
(monomer) 6000
:MM
de secretat
Structura
IANTHIPOGLICEM H.:Functie
pancreas
MIANTHIPERGLICE
insulinei al antogonist
unica
aa 29Structura
de secretat
Functie
pancreas
ticiCaracteris
cuaternarastructura
tertiarastructura
undarasecstructura
primarastructura
obaleg.hidrofd)
hidrogenleg.dec)
leg.ionicab)
hidricaleg.disulf b)peptidica leg.a)
secundara str.
aa) de (secv. peptidica leg.:primara str.
LEGATURI
a
a '
C
NH
C
CO
a
a '
C
NH
C
CO
+
-
a
a '
C
NH
C
CO
a
a '
C
NH
C
CO
+
-
naturale proteineTRANSforma
NC raport in )siC(C transcis izomerie
coplanari
C
H
O
C
C
implica
PEPTIDICE LEG. TICELECARACTERIS
α'α
α'
α
3 posibiliti de dispunere spaial a planurilor formate prin legturi peptidice succesive ale unei catene peptidice
1) Planurile succesive alterneaz unul fa de altul conform a dou orientri spaiale privilegiate => structura "n foi plisate“ (structur de tip periodic);
2) Planurile succesive se rotesc regulat,totdeauna n acelai sens unul n raport cu cellalt => structura de "form helicoidal" (structur de tip periodic);
3) Planurile se pot roti la ntmplare unul fa de altul => structura "n ghem statistic" (structur de tip neperiodic).
R
O
N
H
H
H
C
1
2
34
N
CO
RH
N
C
H
Structura teriar a globinei din mioglobin
Structura cuaternar a colagenului, protein fibrilar cu rol de susinere.Lungile catene polipeptidice ale colagenului sunt dispuse sub form de triplu helix. Structura cuaternar a hemoglobinei, protein globular,ce comport 4 catene polipeptidice i 4 molecule de hem. Oxigenul se ataeaz la structura hemoglobinei prin fierul hemului.
H) atom (MMg 1,67x101dalton
daltoni miloanemiiMM24
Masa moleculara
Insulina (MM = 6.000); Ribonucleaza (MM = 13.700); Ureaza (MM = 480.000)
Masa moleculara
.insolbcompletproteine
;alcalinesolinsolbproteine
;acidesolinsolbproteine
;ielectrolitdesolin.solbproteine
;apain.solbproteine
Solubilitatea
guanidinasiurea
.org.solv
acizii
ionizantesiUVradiatii
caldura
Denaturarea
ionica leg.
H de leg.
SS leg.
idisparitie consecinta
primara str. afectata este nu
spatiale str. areadezorganiz
Definitie
Agenti de denaturare
Denaturarea reversibil a ribonucleazei
osmotica presiune
culoare de reactii
evascozitat
modificare
efunctional grupari noi de aparitia
hidratare de icapacitati pierderea
tiisolubilita diminuarea
biologice iactivitati pierderea
IDENATURARI NILEREPERCUSIU
Caracter coloidal
Caracter amfoter
n sol. diluate =>coloii hidrofili (1-100 m) n sol. concentrate => micele
H2NPROTEINAH3N COO+
- PROTEINA COO- + H+PROTEINAH3N
+COOH
pH=7pH=1pH=11
cation zwiterion anion
CONSECINTA: nu dializeaza prin membrane
Punct izoelectric (pHi)
6,10citocrom
9,6]Hb[pH
1]asinpep[pH
c
i
i
=>separarea, purificarea proteinelor
fanere)(piele, keratina
tendoane)nctiv,(tes.conju colagen
fibroina
einescleroprot
FIBROASE PROTEINE
globuline
albumineinesferoprote
GLOBULARE PROTEINE
natropomiozid)
troponinac)actinab)
miozinaa)
rilare7)Prot.fib
oteine6)Scleroprglutelinee,5)Prolamin
4)Globinehistonee,3)Protamin
e2)Globulin1)Albumine
inecromoprote
einenucleoprot
nelipoprotei
ineglicoprote
inefosfoprote
EINEHETEROPROT
)aa(:NEHOLOPROTEI n
proteine colorate; gruparea prost.
MgCuFe
Definitie
ornerespirat,respiratorrolicaneporfirina,porfirinic str.
Clasificarea cromoproteinelor
](Mg)[clorofilaineCloroplastr
Catalaze
PeroxidazehemininiceEnzime
)(hemCitocrom
)(hemCtocrom
)(hemCitocrom
Citocromi
eHemoglobin
..
nerespi Pigm.
(Fe)respir Pigm.
cc
bb
aa
porfirCr.
minaCeruloplas
naHemocupreiCu
naSiderofili
FeritinaFe
eineMetaloprot
ineFlavoprote
vit.A
arotenβc
arotenαc
oteineCarotenopr
(Cu)eHemocianin
(Fe)eHemiretrin.
pir.Pigm.neres
rPigm.respi
neporfirCr.
Hb = HEM(4%) + GLOBINA(96%)
HEM = protoporfirin + fier
4 nuclee pirolice + =CH- PORFINA
PORFIRINEClade)8(Hasubstituti
PORFINA
NAUROPORFIRI
COOH2
CH2
CHCOOH,2
CHcuesubstituti
PORFINA
HEMATINE
:Exceptie
HEMIPORFIRINE
IRINEMETALOPORF)Mn,Mg,Co,Fe(PORFIRINE
3Fe PORFIRINE
2Fe
IRINA)(PROTOPORFPROTOHEM
metale
CH
HN
H
H H
H
HC
CH
HN
N
N
HC
H
H
H
H
1 2
34
56
7
8
I
II
III
IV
Atomi de carbon si
Atomi de carbon si
'
'
Structura porfinei
HNHN
N
N
1 2
34
56
7
8
I
II
III
IV
CH3
CH2
CHCH3
CH CH2
CH3CH2
CH2
COOH
CH3
HOOC CH2 CH2
Structura PROTOPORFIRINEI
Globina = compon. proteic )(
patologicast.
speciavarsta
iazastruct.var
HEM4)aa146(
)aa141(2icepolipeptidcatene4globina
icapolipeptidcatena1globina
aHemoglobin
Mioglobina
HEM4)aa131(2
)aa141(2peptidicecatenepoli4globina
Hb.FETALA
F2
A2
A2
A2
γαHbF
βαHbA
falciformaanemia
secventadeanomalie
catenederepartitie
catena
valgluEx
catena
catena
APHb
APHbEx
)6()6(:
4.
4.:
Hb.P
obina)(oxihemogl HbO4OHb 4224
4]COHb[CO44]Hb[
1) Combinarea cu oxigenul = oxihemoglobina
2) Combinarea cu CO = carboxihemoglobina
3) Combinarea cu CO2 = carbhemoglobina
OHCONHoteinaPr2NHoteinaPr2CO
ROTEINECARBAMINOPCOsanguine Proteine 2
4) Oxidarea reversibila a Hb = METHEMOGLOBINA
a)ferocianurreducator()3BINA(FeMETHEMOGLO
)ricianuraOxidant(fe)2Hb(Fe