NUCLEIC ACIDS AND PROTEIN SYNTHESIS

DNA complex molecule contains the complete blueprint for every cell in every living thing Amount of DNA that would fit on a pinhead contains information equivalent to that of a stack of paperback books that would encircle the earth 5,000 times Discovered genetic structure- James Watson and Francis Crick in 1953

Each strand of DNA consists of three billion base pairs. Other than sex and blood cells, every cell in your body is making approx. 2,000 proteins every second. 75 trillion cells in your body

How are proteins and DNA related?

Griffith

Avery

Hershey and Chase

Chargaff’s Rule

I.DNA A. Structure 1.DOUBLE STRANDED HELIX- FULL TWIST TEN BASE PAIRS 2. Has histones - proteins

. MONOMER IS NUCLEOTIDE 1. COMPOSED OF THREE PARTS a. 5 CARBON SUGAR - DEOXYRIBOSE b. PHOSPHATE GROUP – PO 4 c. NITROGEN BASES class of organic compounds 1. ADENINE > PURINES 2. GUANINE 3. THYMINE > PYRIMIDINES 4. CYTOSINE PAGE 186 A = T DOUBLE HYDROGEN BOND G ≡ C TRIPLE HYDROGEN BOND

Purines

PYRIMIDINES

II. REPLICATION 1. WHEN DNA DUPLICATES A. UNCOILS AND UNZIPS THE BOND BETWEEN THE BASES - WHERE SEPARATES CALLED REPLICATION FORK 1. SEPARATED BY ENZYMES – HELICASES B. EACH STRAND PICKS UP COMPLEMENTARY NUCLEOTIDE THAT ARE FLOATING IN THE NUCLEUS 1. enzymes DNA polymerases A TO T C TO G C. HAPPENS IN DIFFERENT PLACES ON DNA UNTIL COMPLETED D. RESULTS TWO EXACT COPIES OF DNA E. ORDER OF BASES NOT RANDOM

DNA Replication

DRAW REPLICATION =swf::535::535::/sites/dl/free/ /120076/micro04.swf:: DNA%20Replication%20Fork DNA replication

Semiconservative replication would produce two copies that each contained one of the original strands and one new strand. Conservative replication would leave the two original template DNADNA strands together in a double helix and would produce a copy composed of two new strands containing all of the new DNA base pairs. Dispersive replication would produce two copies of the DNA, both containingDNA distinct regions of DNA composed of either both original strands or both new strands

okazaki fragments

III. FUNCTION 1.CONTROLS PRODUCTION OF PROTEINS WITHIN THE CELL. THE PROTEINS FORM STRUCTURAL UNITS OF THE CELLS AND CONTROL ALL CHEMICAL PROCESSES IN THE CELL

RNA I. STRUCTURE A. MONOMER 1. SINGLE STRAND OF NUCLEOTIDE 2. RIBOSE 5 CARBON SUGAR 3. URACIL INSTEAD OF THYMINE

Compare RNA and DNA

4. 3 DIFFERENT TYPES RNA

a. MESSENGER RNA mRNA 1.UNCOILED CARRIES INFORMATION FROM DNA IN NUCLEUS SERVES AS A PATTERN

b. TRANSFER RNA tRNA 1. HAIRPIN SHAPE, BINDS TO AMINO ACIDS, EACH CAN BOND TO A SPECIFIC AMINO ACID

c. RIBOSOMAL RNA rRNA 1. FOUND IN THE RIBOSOMES

II. TRANSCRIPTION A. HOW mRNA IS PRODUCED FROM DNA 1. DNA UNCOILS AND UNZIPS 2. RNA BASES IN THE NUCLEUS, BOND WITH CORRECT NUCLEOTIDES ON TO DNA 3. WHEN COMPLETED mRNA IS RELEASED 4. DNA REZIPS AND RECOILS B. THE GENETIC CODE OF DNA BECOMES INHERENT IN THE SEQUENCE OF BASES IN mRNA

Practice transcription

III. PROTEIN SYNTHESIS A. PROTEIN STRUCTURE 1. MADE UP OF ___________ 2. _______DIFFERENT TYPES OF _________ SINCE DNA MAKES mRNA, WHICH MAKES PROTEINS, THEN DNA ULTIMATELY CONTAINS THE INFO. NEEDED TO PUT THE AMINO ACIDS IN THE PROPER ORDER

B. CODONS 1. A SPECIFIC GROUP OF 3 SEQUENTIAL BASES OF mRNA 2. EACH CODON IS FOR A SPECIFIC AMINO ACID POSSIBLE CODONS a. START - AUG b. STOP - UAA, UAG, UGA C. ANTICODONS 1. A SPECIFIC GROUP OF 3 SEQUENTIAL BASES OF t RNA

EXAMPLES CODON CAU ANTICODON _____ PAGE 194

DNA ↕ mRNA ↔ amino acid ( chart) ↕ tRNA

Practice

protein synthesis

D. TRANSLATION 1. PROCESS OF MAKING PROTEINS 2. WHEN the tRNA ANTICODON MATCHES WITH CODON OF mRNA

Protein synthesis 1. DNA UNCOILS 2. DNA UNZIPS 3. mRNA NUCLEOTIDE ATTACH TO DNA CALLED__________ 4. mRNA COMPLETED BREAKS AWAY 5. DNA STRAND REJOINS AND RECOILS 6. mRNA LEAVES NUCLEUS GOES TO RIBOSOMES 7. SPECIFIC A.A. COMBINE WITH tRNA GOES TO RIBOSOMES HAPPENS IN CYTOPLASM 8. RIBOSOMES MOVES ALONG mRNA; ANTICODONS MATCH WITH CODONS CALLED ____________ 9. END OF mRNA STRAND CODON CODES FOR STOPPING (THE END) 10. AA. ARE JOINED; tRNA RELEASED RETURNS TO CYTOPLASM 11. PROTEIN BREAKS AWAY AND USED BY THE CELL 12. mRNA BREAKS UP

To begin translation, the small subunit first identifies, with the help of other protein factors, the precise point in the RNA sequence where it should begin linking amino acids, the building blocks of protein. The small subunit, once bound to the mRNA, is then joined by the large subunit and translation begins.

A – amino acid P – making the peptide E- exit

The small subunit is involved in decoding the genetic information, while the large subunit has the catalytic activity responsible for peptide bond formation (that is, the joining of new amino acids to the growing protein chain).

Translation Making Proteins

protein synthesis

Order Twists and folds Folds, twists and bonds to self

Primary Structure The primary structure of a polypeptide or protein is the sequence of amino acids in the protein. In the case of insulin shown here there are two polypeptide chains in the primary structure. Human Insulin Primary structure. Each three letter abbreviation stands for one of the twenty basic amino acids found in living things: Chain 1 GLY- ILE -VAL- GLU -GLN -CYS -CYS -THR- SER -ILE -CYS- SER -LEU - TYR -GLN -LEU -GLU -ASN -TYR -CYS -ASN Chain 2 PHE -VAL -ASN-GLN -HIS -LEU -CYS- GLY- ASP -HIS – LEU- VAL- GLU- ALA -LEU- TYR -LEU- VAL- CYS- GLY- GLU- ARG -GLY- PHE -PHE -TYR - THR -PRO -LYS -THR

Secondary Structure Secondary structure refers to the folding of the chain of amino acids into a helix or a pleated sheet.

Tertiary Structure Tertiary structure refers to a higher level of folding

Quaternary structure Quaternary structure arises when polypeptide chains are bound together usually by hydrogen bonds. For example hemoglobin the oxygen carrying protein in blood