21 - 1ch110 – nucleic acids nucleic acids nucleic acids nucleic acids: –maintain genetic...

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21 - 1 H110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids Nucleic acids: Maintain genetic information Maintain genetic information Determine Protein Synthesis Determine Protein Synthesis DNA DNA = deoxy deoxyribonucleic acid Master Copy” for most cell information. Template for RNA RNA = RNA = ribonucleic acid Transfers information from DNA Template for Proteins

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Page 1: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 1CH110 – Nucleic Acids

Nucleic acidsNucleic acids

Nucleic acidsNucleic acids: – Maintain genetic informationMaintain genetic information– Determine Protein SynthesisDetermine Protein Synthesis

DNADNA = deoxydeoxyribonucleic acid– “Master Copy” for most cell information.– Template for RNA

RNA =RNA = ribonucleic acid– Transfers information from DNA– Template for Proteins

Page 2: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 2CH110 – Nucleic Acids

Nucleic AcidsNucleic AcidsChromosomes

(in nucleus)

Have genesgenes

1 gene

1 enzyme

EnzymesEnzymes determine determine

external & internal characteristicsexternal & internal characteristics

Page 3: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 3CH110 – Nucleic Acids

NUCLEIC ACIDSNUCLEIC ACIDS

Long chains (polymers) of repeating nucleotides.nucleotides.– Each nucleotide has 3 parts:3 parts:

A A phosphate unitphosphate unit H H

OO

H

H

OH

H

H

HO

A sugarsugar

A heterocyclic heterocyclic Amine BaseAmine BaseN

H

P OH

O

OH

HO

Page 4: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 4CH110 – Nucleic Acids

NucleoNucleottide ide = phosphate + sugar + base= phosphate + sugar + baseNucleoNucleottide ide = phosphate + sugar + base= phosphate + sugar + base

P

O

O

ON

H H

OH

OH

H

H

O

-N-glycosidiclinkage

-N-glycosidiclinkage

BaseBase

SugarSugar

PhosphatePhosphate

Nucleoside = Nucleoside = sugar + basesugar + baseNucleoside = Nucleoside = sugar + basesugar + base

Page 5: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 5CH110 – Nucleic Acids

Nucleic AcidsNucleic Acids

Nucleic AcidsNucleic Acids = polymerspolymers of Nucleotides.Nucleotides.

phosphate sugar

base

SS SS SSSSSSSS

BB BB BBBBBBBB

PPPP PP PPPPPP

Page 6: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 6CH110 – Nucleic Acids

THE SUGAR PARTTHE SUGAR PART• The major difference between RNA and DNA is

the different form of sugar used.

OHOCH2

H HHH

OH OHOH

OHOHOCH2

H HHH

OH HH

OH

Ribose C5H10O5

in RNADeoxyDeoxyRibose C5H10O4

in DNA

The difference is at carbon #2carbon #2.

Page 7: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 7CH110 – Nucleic Acids

The Nitrogenous BasesThe Nitrogenous Bases

5 bases5 bases used fall in two classestwo classes

Purines Purines & & PyrimidinesPyrimidines

N

N

N

NH

A double ringdouble ring (6 & 5 members)

A single ringsingle ring(6 membered)

N

N

Page 8: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 8CH110 – Nucleic Acids

Pyrimidines:Pyrimidines:

The Nitrogenous BasesThe Nitrogenous Bases

Purines:Purines:N

N

N

N

NH2

H

N

N

N

NH

H2N

O

H

N

N

O

O

CH3

H

HN

N

O

O

H

H N

NO

H

H

NH2

Adenine (A)Adenine (A)Adenine (A)Adenine (A) Guanine (G)Guanine (G)Guanine (G)Guanine (G)

Thiamine (T)Thiamine (T)In In DNADNA only onlyThiamine (T)Thiamine (T)In In DNADNA only only

Uracil (U)Uracil (U)In In RNARNA only only

Uracil (U)Uracil (U)In In RNARNA only only

Cytosine (C)Cytosine (C)Cytosine (C)Cytosine (C)

Page 9: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 9CH110 – Nucleic Acids

Nucleotides Di- & Tri- Phosphates Nucleotides Di- & Tri- Phosphates

P

O

OH

HO OH

Adenosine 5’-monophosphate(AMP)

Adenosine 5’-monophosphate(AMP)

riboseribose

AdenineAdenineN

N

N

N

NH2

P

O

O

HO

H H

OH

OH

H

OH

O

1'

2'3'

4'

5'

Page 10: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 10CH110 – Nucleic Acids

Adenosine 5’-monophosphate(AMP)

Adenosine 5’-monophosphate(AMP)

riboseribose

AdenineAdenine

P

O

OH

HO OH

N

N

N

N

NH2

P

O

O

O

H H

OH

OH

H

OH

OP

O

HO

O 1'

2'3'

4'

5'

Adenosine 5’-diphosphate (ADP)Adenosine 5’-diphosphate (ADP)

Nucleotides Di- & Tri- Phosphates Nucleotides Di- & Tri- Phosphates

Page 11: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 11CH110 – Nucleic Acids

Adenosine 5’-monophosphate (AMP)

Adenosine 5’-monophosphate (AMP)

riboseribose

AdenineAdenine

Adenosine 5’-diphosphate (ADP)Adenosine 5’-diphosphate (ADP)

Adenosine 5’-triphosphate (ATP)Adenosine 5’-triphosphate (ATP)

P

O

O

HO O

N

N

N

N

NH2

P

O

O

O

H H

OH

OH

H

OH

OP

O

O

O 1'

2'3'

4'

5'

Nucleotides Di- & Tri- Phosphates Nucleotides Di- & Tri- Phosphates

Page 12: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 12CH110 – Nucleic Acids

H

N

N

N

N

NH2

P

O

O

H H

OH

OH

H

O

OH

1'

2'3'

4'

5'

H

HN

N

N

NP

O

O

H H

OH

OH

H

O

OH

O

H2N

1'

2'3'

4'

5'

1'

2'3'

4'

5'

H

N

P

O

O

H H

OH

OH

H

O

OH

N

O

O

CH3

Primary structurePrimary structure

Page 13: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 13CH110 – Nucleic Acids

H

N

N

N

N

NH2

P

O

O

H H

OH H

O

OH

H

HN

N

N

NP

O

O

H H

OH H

O

O

O

H2N

H

N

P

O

O

H H

OH

OH

H

O

N

O

O

CH3

O

1'

2'3'

4'

5'

1'

2'3'

4'

5'

1'

2'3'

4'

5'

Primary structurePrimary structure

Phosphate bondsPhosphate bondslink DNA or RNAlink DNA or RNAnucleotides togethernucleotides togetherin a linear sequence.

Similar to proteinswith their peptide

bonds and sidegroups.

5’

3’

Adenine (A)

Guanine (G)

Thymine (T)

Page 14: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 15CH110 – Nucleic Acids

Base pairing and hydrogen bondingBase pairing and hydrogen bonding

N

N

O| |

- H

N - H

N

NN

N

O| |

H - N

N

N O| |

O| |

H3C

- H

guanine cytosine

thymine adenineN

N N

N|

HH

N

Page 15: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 16CH110 – Nucleic Acids

Complementary Base PairingPosition of H bonds and distance match with:

DNA - DNA - Secondary StructureSecondary Structure

Page 16: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 17CH110 – Nucleic Acids

Hydrogen bondingHydrogen bonding

Each base wants toform either two or three hydrogen bonds.

That’s why only certain bases will form pairs.

G

T

C

A

C G

A

C

T

G

Page 17: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 18CH110 – Nucleic Acids

Sugar-Sugar-phosphate phosphate backbonebackboneDNA coilscoils around outsideoutside of of attached attached basesbases like a spiral stair case.

Results in a double helix structure.

Page 18: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 19CH110 – Nucleic Acids

The double helixThe double helix

The combination of the stairstep sugar-phosphate backbone and the bonding between pairs resultsin a double helix.

The combination of the stairstep sugar-phosphate backbone and the bonding between pairs resultsin a double helix.

Distance betweenbases = 0.34 nm

2 nmbetweenstrands

One complete

twist is 3.4 nm

Page 19: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 20CH110 – Nucleic Acids

DNA - DNA - Secondary StructureSecondary Structure

Complementary Base Pairing

Page 20: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 22CH110 – Nucleic Acids

• Crick and Watson (1962 Nobel Prize)

– Proposed the basic structure of DNA

– 2 strands wrap around each other

– Strands are connected by H-bonds between the amines.• Like steps of a spiral

staircase

Page 21: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 23CH110 – Nucleic Acids

ChromosomesChromosomes

Chromosomes consists of DNA strands coiledaround protein - histomes. The acidic DNA’s areattracted to the basic histones.

Page 22: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 24CH110 – Nucleic Acids

Page 23: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 25CH110 – Nucleic Acids

ChromosomesChromosomes

The normal number of chromosome pairs varies among the species.

AnimalAnimal Pairs Pairs PlantPlant PairsPairsMan 23 Onion 8Cat 30 Rice 14Mouse 20 Rye 7Rabbit 22 Tomato 12Honeybee, White pine 12

male 8 Adder’s 1262female 16 tounge fern

Page 24: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 28CH110 – Nucleic Acids

TTCC

AA

SS SSSS SSSSSS

GG TT CCAA

PPPP PP PPPPPP

CC GG

GG

DNA: Self - ReplicationDNA: Self - Replication

Page 25: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 29CH110 – Nucleic Acids

GGGGAA

SS SSSS SSSSSS

GG TT CCAA

PPPP PP PPPPPP

CC GG

DNA: Self - ReplicationDNA: Self - Replication

TT CCCC

Page 26: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 30CH110 – Nucleic Acids

Replication of DNAReplication of DNA

ReplicationReplication occurs on both halvesboth halvesin opposite directions.opposite directions.

Page 27: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 31CH110 – Nucleic Acids

DNA DNA ReplicationReplication

Page 28: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 32CH110 – Nucleic Acids

RNA synthesisRNA synthesis

In the first step, RNA polymeraseRNA polymerase bindsto a promotorpromotor sequenceon the DNA chain.

This insuresinsures that transcription occurs in the correct directioncorrect direction.

The initial reaction is toseparate the twoseparate the twoDNA strandsDNA strands.

Page 29: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 33CH110 – Nucleic Acids

RNA synthesisRNA synthesis

initiationsequence

terminationsequence

‘Special’ baseSpecial’ basesequencessequences in theDNA indicatewhere RNARNAsynthesis startssynthesis startsand stops.and stops.

Page 30: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 34CH110 – Nucleic Acids

RNA synthesisRNA synthesis

Once the terminationsequence isreached, thenew RNA moleculenew RNA moleculeand the RNA synthaseare released.released.

The DNA recoils.The DNA recoils.

Page 31: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 35CH110 – Nucleic Acids

• The messenger RNAmessenger RNA (mRNA) move outside the nucleus to the cytoplasmto the cytoplasm where RibosomesRibosomes are anxiously awaiting their arrival.

rRNA40 S

60 SrRNA

Page 32: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 36CH110 – Nucleic Acids

• The messenger RNAmessenger RNA (mRNA) move outside the nucleus to the cytoplasmto the cytoplasm where RibosomesRibosomes are anxiously awaiting their arrival.

rRNA40 S

60 SrRNA

Page 33: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 37CH110 – Nucleic Acids

• The messenger RNAmessenger RNA (mRNA) move outside the nucleus to the cytoplasmto the cytoplasm where RibosomesRibosomes are anxiously awaiting their arrival.

rRNA40 S

60 SrRNA

Page 34: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 38CH110 – Nucleic Acids

• The messenger RNAmessenger RNA (mRNA) move outside the nucleus to the cytoplasmto the cytoplasm where RibosomesRibosomes are anxiously awaiting their arrival.

rRNA40 S

60 SrRNA

Page 35: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 39CH110 – Nucleic Acids

rRNA40 S

60 SrRNA

Ribosomal RNA – rRNARibosomal RNA – rRNA: Platform for protein synthesis. Holds mRNA in place and helps assemble proteins.

Page 36: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 40CH110 – Nucleic Acids

40 S

AUG GCU AUG UUG

5’

3’

rRNArRNA

60 S

•The RibosomesRibosomes are like train stationslike train stations

–The mRNA is the trainmRNA is the train slowly moving through the station.

rRNArRNA

Codons

mRNAmRNA

Page 37: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 41CH110 – Nucleic Acids

Transfer RNA Transfer RNA - tRNA- tRNA =• relatively small small compared to other RNA’s

(70-90 bases.)70-90 bases.)• transports amino acidstransports amino acids to site of protein synthesis.

A

C

C

A

C

C

U

C

G

U

CU

U

C

G

G

G

G

G

CC GGG

CC GG

A CGG

CC GGU

C

C

C

C

U

C

A

U

G

G

A

G

G

G

G

GU

U

CC G

U

C GC

AU

G

G

C

U

AG U

A GU

G

GC

HO-A

C

C

A

C

C

U

C

G

U

CU

U

C

G

G

G

G

G

CC GGG

CC GG

A CGG

CC GGU

C

C

C

C

U

C

A

U

G

G

A

G

G

G

G

GU

U

CC G

U

C GC

AU

G

G

C

U

AG U

A GU

G

GC

HO-

Page 38: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 42CH110 – Nucleic Acids

Anticodons on t-RNAAnticodons on t-RNA

A

C

C

A

C

C

U

C

G

U

CU

U

C

G

G

G

G

G

CC GGG

CC GG

A CGG

CC GGU

C

C

C

C

U

C

A

U

G

G

A

G

G

G

G

GU

U

CC G

U

C GC

AU

G

G

C

U

AG U

A GU

G

GC

HO-

Site of aminoacid attachment

Site of aminoacid attachment

Three base anticodon site

Three base anticodon site

Point ofattachmentto mRNA

Point ofattachmentto mRNA

Page 39: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 43CH110 – Nucleic Acids

Amino acid codonsAmino acid codons

alanine GCA, GCC, GCGGCU, AGA, AGG

arginine AGA, AGG, CGACGC, CGG, CGU

asparagine AAC, AAUaspartate GAC, GAU cysteine UGC, UGUglutamate GAA, GAGglutamine CAA, CAGglycine GAA, GCC, GGG

GGUhistidine CAC, CAUisoleucine AUA, AUC, AUUleucine CUA, CUC, CUG

CUU, UUA, UUG

lysine AAA, AAGmethionine AUGphenylalanine UUC, UUUproline CCA, CCC

CCG, CCUserine UCA, UCC

UCG, UCU AGC, AGU

threonine ACA, ACC ACG, ACU

tryptophan UGGtyrosine UCA, UCUvaline GUA, GUC

GUG, GUU

Page 40: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 45CH110 – Nucleic Acids

Protein SynthesisProtein Synthesis1: Activation1: Activation

Each AA is activated by reacting with an ATP

The activated AA is then attached to particular tRNAtRNA... (with the correct anticodon)

C G A

fMET

anticodon

activated AA

Page 41: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 46CH110 – Nucleic Acids

60S

TranslationTranslation

40S

AUG GCU AUG UUG mRNA

5’

3’

Initiationfactors

ribosome unit

U A C

fMET

PPsitesite AA site site

Page 42: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 47CH110 – Nucleic Acids

U A C

fMET

TranslationTranslation

40S ribosome unit

AUG GCU AUG UUG mRNA

5’

3’

60S

PPsitesite AA site site

C G A

Ala

Page 43: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 48CH110 – Nucleic Acids

ribosome unit

AUG GCU AUG UUG mRNA

5’

3’

TranslationTranslation

U A C

fMET

C G A

Ala

peptide bondforms

Page 44: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 49CH110 – Nucleic Acids

ribosome unit

GCU UUC UUGmRNA

5’

3’

TranslationTranslation

C G A

Ala

peptide bond

Met

Z Z Z

Amino Acid

AU G

U A C

U A C

Page 45: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 50CH110 – Nucleic Acids

ribosome unit

GCU UUC UUGmRNA

5’

3’

TranslationTranslation

C G A

Ala

peptide bondforms

Met

? ? ?

???

AU G

U A C

Page 46: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 53CH110 – Nucleic Acids

Recombinant DNARecombinant DNA

Bacterium

Remove gene segment

DNAPlasmid sticky ends

Cut genefor insulin

Replace inbacterium

Page 47: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 54CH110 – Nucleic Acids54

Learning CheckLearning Check

What is the sequence of bases in mRNA producedfrom a section of the template strand of DNA that

hasthe sequence of bases: 3’–C–T–A–A–G–G–5’?

1. 5’–G–A–T–T–C–C–3’

2. 5’–G–A–U–U–C–C–3’

3. 5’–C–T–A–A–G–G–3’

Page 48: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 55CH110 – Nucleic Acids55

SolutionSolution

What is the sequence of bases in mRNA producedfrom a section of the template strand of DNA that

hasthe sequence of bases: 3’–C–T–A–A–G–G–5’?

3’–C–T–A–A–G–G–5’?

2. 5’–G–A–U–U–C–C–5’

Page 49: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 56CH110 – Nucleic Acids56

The following section of DNA is used to build a mRNA

for a protein. 3’—GAA—CCC—TTT—5’

A. What is the corresponding mRNA sequence?

B. What are the anticodons on the tRNAs?

C. What is the amino acid order in the peptide?

Learning CheckLearning Check

Page 50: 21 - 1CH110 – Nucleic Acids Nucleic acids Nucleic acids Nucleic acids: –Maintain genetic information –Determine Protein Synthesis DNAdeoxy DNA= deoxyribonucleic

21 - 57CH110 – Nucleic Acids57

3’—GAA—CCC—TTT—5’ DNAA. What is the corresponding mRNA sequence?

5’—CUU—GGG—AAA—3’ mRNA

B. What are the anticodons for the tRNAs?mRNA codons CUU GGG AAAtRNA anticodons GAA CCC UUU

C. What is the amino acid order in the peptide? mRNA 5’—CUU—GGG—AAA—3’ Leu — Gly — Lys

SolutionSolution