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  • 1Polinukleotida(Struktur DNA)

    copyright cmassengale

  • DNA

    Material genetik pada mahluk hidup adalah Asam nukleat (DNA atau RNA)yaitu suatu polimer nukleotida yg berperanan dlm penyimpanan serta pemindahan informasi genetik

  • Bukti bahwa DNA adalah material

    genetik

  • Transformation Fred Griffith menggunakan strain

    bakteri S.pneumoniae virulen tipe S and nonvirulent tipe R

    Smooth Streptococcus

    pneumoniae (pneumococci)

    Rough Streptococcus

    pneumoniae (pneumococci)

  • 601 20000

    Chapter 2 slide 5

    Peter J. Russell, iGenetics: Copyright Pearson Education, Inc., publishing as Benjamin Cummings.

    Griffiths transformation experiment

  • 6Transformation Dia menemukan bhw strain tipe R

    dapat menjadi virulent ketika mengambil DNA (transformasi) dari strain tipe S yg sudah mati

    Penelitian ini menunjukkan bahwa DNA adalah adalah material genetik

  • Peter J. Russell, iGenetics: Copyright Pearson Education, Inc., publishing as Benjamin Cummings.

    Oswald T. Averys Transformation Experiment - 1944

    Determined that IIIS DNA was the genetic material responsible for Griffiths results (not RNA).

  • Support for Avery

    Alfred Hershey and Martha Chase- in 1952, used bacteriophage (T2) as a model.

  • Fig. 16.3

  • Structure of Viruses

    bacterial viruses may have tails and related structures

    T4

    virus

  • Structure of Viruses

  • Support for Avery

    They radiolabeled the protein coat with 35S and the DNA with 32P in order to see which of the molecules actually entered the cell and produced more phage.

  • Fig. 16.4: Hershey-Chase Exp.

  • DNA/RNA

    Asam nukleat terdapat dlm 2 bentuk, yaitu asam deoksiribosa (DNA) dan asam ribosa (RNA).

    Pd sel eukariot, DNA terdapat di dlmnukleus,

    pada sel prokariot, terdpt dlmsitoplasma dalam bentuk nukleoid.

  • StrukturDNA

  • DNATersusun atas subunit ygdisebut nukleotidaNukleotida terdiri atas: Gugus phosphate Gula berkarbon-5 Basa Nitrogen

  • DNA Gula pentose (Deoxyribose) terikat ke gugus phosphat (PO4) groups melalui ikatan phosphodiester

    Ikatan antara molekul deoxiribosa dengan basa-basa nitrogen disebut ikatan glikosida

  • 18

    Nukleotida DNA

    O=P-OO

    PhosphateGroup

    NNitrogenous base(A, G, C, or T)

    CH2

    O

    C1C4

    C3 C2

    5

    Sugar(deoxyribose)

    O

  • 19

    Gula Pentosa Tersusun atas 5 atom karbon yg

    dinotasi 1 - 5

    CH2

    O

    C1C4

    C3 C2

    5

    Sugar(deoxyribose)

  • 20

    Basa2 Nitrogen

    Double ring PURINAdenine (A)Guanine (G)

    Single ring PYRIMIDINThymine (T)Cytosine (C) T or C

    A or G

  • Pasangan-basa Purin hanya berpasangan dgn Pirimidin

    Pasangan antara Guanin & sitosin membentuk tiga ikatan hidrogen

    CG

    3 H-bonds

  • 22

    T A

    Pasangan antara Timin & Adenin membentuk dua ikatan hidrogen

  • Ikatan Hidrogen

    H

    H

    H H

    O

    O

    H

    C

    C

    C C

    N

    N

    C

    TiminH

    N

    H

    H

    N

    C C

    C

    C

    N

    N H

    N

    C

    Adenin

    H

    O

    N

    H C

    C C

    N

    N

    C

    Sitosin

    H

    H

    H

    N

    C C

    C

    C

    N

    N H

    N

    C

    Guanin

    NH

    O

    H

  • 5 end

    3 end

    Perbedaan DNA dan RNA

  • 25

    DNA (Polinukleotida)

    P

    P

    P

    O

    O

    O

    1

    23

    4

    5

    5

    3

    3

    5

    P

    P

    PO

    O

    O

    1

    2 3

    4

    5

    5

    3

    5

    3

    G C

    T A

  • Three Dimensional Structure of DNA

    Rosalind Franklin- X-ray crystallography of DNA- showed that DNA was in a helix with PO4 and sugars to the outside.

    James Watson and Francis Crick-took Franklins data- in April 23, 1953, and deduced the structure of DNA. Won the Nobel Prize along with Maurice Wilkins.

  • 1962: Nobel Prize in Physiology and Medicine

    James D.Watson

    Francis H.Crick

    Maurice H. F.Wilkins

    What about?Rosalind Franklin

  • 29

    Untai ganda ygbersifat Antiparalel

    Satu untai tumbuh dari

    5 ke 3 (gula)

    Untai yang lain memiliki arah yg berlawanan dari 3 ke 5

  • 5 end

    3 end

  • 32

    DNA Double Helix

    NitrogenousBase (A,T,G or C)

    Rungs of ladder

    Legs of ladder

    Phosphate &Sugar Backbone

  • Type A, B, and Z conformations of DNA

  • Type B-DNA

    Other DNA forms include:

    A-DNA:Right-handed double helix with 11 bases per turn; shorter and wider at 2.2 nm diameter. Exists in some DNA-protein complexes.

    Z-DNA:Left-handed double helix with 12 bases per turn; longer and thinner at 1.8 nm diameter.

  • Characteristics of DNA

    All chains of DNA and RNA have a 5 PO4 end and a 3 OH end.

    Base sequences are written in a 5 to 3 direction.

    Ex. 5 pGpTpCpCpApT-OH 3 or

    - GTCCAT -

  • Characteristics of DNA

    Base pairs stabilize the molecule by forming H-bonds.

    Antiparallel Strands-

    5----------------3

    3----------------5

    Strands are complementary.

  • Discovery of DNA Structure

    Erwin Chargaff menunjukkan jumlah dari basa penyusun DNA ( A,T,C,G)

    Pada sel somatik:A = 30.3%T = 30.3%G = 19.5%C = 19.9%

  • Genome: Keseluruhan gen/DNA yang ada di

    dalam sel hidup.

    Gene:Urutan nukleotida yang mengkode

    suatu protein.

  • Two types of organism: Eukaryotes; cells contain membrane-bound

    compartments, including a nucleus and organelles.

    Eukaryotes include: animals, plants, fungi, and

    protozoa.

    Prokaryotes: Lack internal compartments extensively.

    Divided into two groups: bacteria and archaea.]

  • 553

    3

    exon exonintronupstream downstream

    Initiation codon termination codon

  • Gene organization in genomes

  • Circular shape of microbial DNA

  • 601 20000

    Chapter 2 slide 44

  • Terima kasih