Transcript and stop - kesmasums2011

BIOLOGI MOLEKULER
BIOSINTESIS PROTEIN
Oleh:
BAGIAN BIOKIMIA
FAKULTAS KEDOKTERAN UNS
2008
MAKNA SINTESIS PROTEIN
• MEKANISME ANTIBIOTIK DALAM
MEMBUNUH BAKTERI DENGAN
MENGHAMBAT SINTESIS PROTEIN
DINDING BAKTERI
• ANTIBIOTIK ADA YANG BERSIFAT
SELEKTIF MENGHAMBAT SINTESIS
PROTEIN DINDING BAKTERI SAJA,
TETAPI ADA YG MENGHAMBAT
KEDUANYA
Dogma of molecular biology
Produk akhir gen adalah protein
Structure of eucaryotic cells
lysosomes
nucleus
nucleolus
cell membrane
mitochondria
rEPR (ribosomes)
sEPR
centrosome
cytoplasm
Golgi
Fungsi organela sel
organelle
major functions
cell membrane
nucleus
nucleolus
centrosome
cytoplasm
mitochondria
ribosomes
lysosomes
rEPR
sEPR
Golgi
cell integrity, signal transduction
replication, transcription
ribosome synthesis (subunits)
cell division
metabolic pathways, signaling
ATP synthesis, DNA
protein synthesis
intracellular degradation
protein synthesis (export)
lipid synthesis, membranogenesis
protein transport (addressing)
Structure of mammalian genes
REGULATION
STRUCTURE
I1
5‘
REGULATION
E1
E - exons (coding)
I - introns (non-coding)
I2
E2
E3
promoter
enhancer
silencer
3‘
Structural parameters of a gene
and of a mRNA (comparison)
Gene
- 5‘-flanking region, structural part, 3‘-flanking region
- exons (coding) and introns (non-coding)
- no real start, no real stop
cDNA (mRNA)
- 5‘-UTR, coding region, 3‘-UTR
- no uncoding region between start and stop
- start (cap-site) and stop (poly-A tail)
Processes involved in gene
transcription
start
DNA
stop
E1
E2
transcription + capping
E3
poly A
signal
termination
signals
CAP
pre-mRNA
polyadenylation
AAAAAA
mRNA
splicing
start
AAAAA
stop
Jenis RNA
ribosomal RNA (rRNA)
5 S, 5.8 S (160 bp), 18 S (2000 bp) and 28 S (5000 bp) RNA
ribosome structure
transfer RNA (t-RNA)
small RNA species with characteristic secondary structure
(anticodon, amino acid binding)
amino acid transfer
messenger RNA (mRNA)
matrix for protein synthesis at the ribosome, different
length
translation
Struktur mRNA
gene
I1
E1
5‘
I2
E3
E2
3‘
PAS
pre-mRNA
AUG
(start)
mRNA
splicing sites
PAS
CAP
5‘-UTR
start
UGA
(stop)
TR
AAAAAAA
3‘-UTR
stop
Struktur mRNA jadi
CAP
regulatory parts
structural part
5‘-UTR
start
codon
3‘-UTR AAAAA
TR
stop
codon
Genetic code
degenerated code:
stop
stop
several triplets code for one amino acid,
only methionine (start) has just 1 codon
stop
Bahasa gen
bersifat
universal
KODON ATAU SANDI GENETIK
TRIPEL NUKLEOTIDA
LIHAT VCD SINTESIS
PROTEIN
• DARI MCB
• DARI SI NTESIS PROTEIN LEHNINGER 2000
• DARI HRN YAHYA
BIOSINTESIS PROTEIN
• PERHATIKAN TEORI DOGMA SENTRAL, PRODUK
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AKHIR GEN ADALAH PROTEIN
DNA SEBAGAI MATERI GENETIK
mRNA SEBAGAI PEMBAWA INFORMASI GENETIK
SINTESIS PROTEIN TERJADI DI RIBOSOM
mRNA MEMBAWA CODON, SEDANGKAN tRNAMEMBAWA ANTI CODON
PESANAN ASAM AMINO DIKODE OLEH CODON mRNA
ASAM AMINO YANG SATU DENGAN YANG LAIN
DIRANGKAI DENGAN IKATAN PEPTIDA
START CODON SELALU DIMULAI DENGAN METIONIN
DAN SINTESIS PROTEIN DIAKHIRI DENGAN STOP
CODON
TABEL KODON
Amplification of Message by Translation
From 1 spliced mRNA molecule many protein molecules are made.
SINTESIS PROTEIN SELALU DIMULAI
DENGAN METIONIN
TERMINASI DENGAN STOP CODON
Structure levels in proteins
primary structure
amino acid sequence
secondary structure
spatial arrangement of amino acids within a polypeptide chain (a-helix, ß-sheet, unstructured turns)
tertiary structure
spatial arrangement of secondary structural elements
quatery structure
subunit interactions
Amino acids are constituents of
proteins
there are about 20 proteinogenic amino acids
Proteins are Made of AAs Connected
by Peptide Bonds
• Ikatan peptida bersifat ikatan rangkap
spt 2 lembar kertas yang dilem (SRTLH)
arti dipeptida, tripeptida, jml AA & ikt pep
• Pada praktikum: berwarna ungu
IMUNOBLOTING
kDa
kDa Koloni yg mengeksp
protein rekombinan
diimunobloting dg Ab
poliklonal thd Prot sol T.
gondii
97,4 kDa
84,0 kDa
66,0 kDa
55,0 kDa
45,0 kDa
29,0 kDa
20,1 kDa
14,2 kDa
1
2
3
4
5
6
7
Pita prot rek gb pita
berbeda dg prot non rek,
28 intensitas warna
berbeda,yg dominan prot
rek dg BM 28 kDa yg
merup hasil eksp cDNA
Gambar 6. Hasil elektroforesis protein dari biakan E.coli rekombinan pembawa
gen penyandi protein solubel 28 kDa (GRA2) T. gondii yang diimunobloting dengan
antibodi poliklonal terhadap protein solubel takizoit T. gondii.
1. protein standar, 2. lisat protein dari E.coli dengan pewarnaan amidoblack,
4, 5, 6 dan 7 adalah hasil imunobloting protein dari klon rekombinan, sedang
3 adalah protein dari klon berwarna biru ( bukan rekombinan)
APLIKASI KLINIS
• WESTERN BLOT UNTUK DIAGNOSIS
HIV
• STRUKTUR PROTEIN
Proteins Form Complex 20 Structures
• R Groups define the
behavior of an amino
acid and the structure
a protein domain folds
into.
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Acidic
Basic
Neutral
Hydrophobic
Hydrophilic
Electrostatic
MACAM DAN FUNGSI
PROTEIN
1. Protein Regulator / Bioregulator( Hormon)
2. Biokatalisator ( Enzim )
3. Protein Transport: Hb, Alb,
Lipoprotein,Transferin
4. Protein Kontraktil: aktin dan miosin
5. Protein Struktural:
kolagen,tubulin,keratin,glikopr
6. Protein Pelindung: Ig, interferon,
perforin,IL
HEALTH is better than
WEALTH
Biomol: Dx dini, patogenesis,
protein kandidat vaksin dan tx gen
Thank you for
your kind
attentions ..
TERIMA KASIH