Where is Cytochrome C?

What is the role? Where does it come from?

Evolutionary Biology of Cytochrome C

• Cytochrome c is a highly conserved protein.

• Its primary structure consists of a chain of 100 aa.

• Both chicken and turkeys have the identical molecule whereas ducks p differ by one amino acid.

• Similarly, both humans and chimpanzees have the identical molecule.

Where does protein come from?

The information for building proteins is stored in our DNA. DNA codes for

proteins like cytochrome C.

DNA RNA Protein

Gene expression

If the DNA in a single human cell were stretched out and laid end-to-end, it would measure approximately 6.5 feet. The average human body contains 10 to 20

billion miles of DNA distributed among trillions of cells.

Cytochrome CGene for Cytochrome C

Understanding How Cells Build Essential Proteins

DNA StructureDouble helix

WC Base pairStructure of a

Gene

Understanding how genes are expressed

DNA RNAProtein

DNA is a double-stranded helixJames Watson and Francis Crick

Worked out the three-dimensional structure of DNA, based on work by Rosalind Franklin

http://www.dnai.org/

Figure 10.3A, BTwist

DNA polynucleotide

A

C

T

G

T

Sugar-phosphate backbone

Phosphate group

Nitrogenous base

Sugar

A

C

T

G

T

Phosphategroup

O

O–

OO P CH2

H3CC

C

C

CN

C

N

H

H

O

O

C

O

O

H

C H H

H

C

H

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

Thymine (T)

Sugar(deoxyribose)

DNA nucleotide

DNA nucleotide

DNA is a nucleic acid• Made of long chains of nucleotide monomers• Remember that ATP was a nucleotide

Figure 10.2A

Double Helix StructureMajor/minor grooveAnti-parallel strands

DNA has four kinds of nitrogenous bases• A, T, C, and G

CC

C

CC

C

O

N

C

H

H

ONH

H3C

H H

H

H

N

N

N

H

OC

H HN

H C

N

N N

N

C

CC

C

H

H

N

N

H

C

CN

C HN

CN

H C

O

H

H

Thymine (T) Cytosine (C) Adenine (A) Guanine (G)

PurinesPyrimidines

Figure 10.2B

DNA Strands: Anti-parallel

Each strand of the double helix is oriented in the opposite direction

Figure 10.5B

P

P

P

P

P

P

P

P

HO

OH

A

C

G

T

T

C

G

A

21

34

5

15

4

32

5 end 3 end

3 end 5 end

Understanding How Cells Build Essential Proteins

DNA StructureDouble helix

WC Base pairStructure of a

Gene

Understanding how genes are expressed

DNA RNAProtein

DNA nevers leaves the nucleas but the information does!

T A C T T C A A A A T C

A T G A A G T T T T A G

A U G A A G U U U U A G

Transcription

Translation

RNA

DNA

Met Lys PhePolypeptide

Startcondon

Stopcondon

Strand to be transcribed

The information constituting an organism’s genotype

is carried in its sequence of its DNA bases. “ATGACTAA”

A particular gene, a linear sequence of many nucleotides

Specifies a polypeptide

“MET-LYS-LEU”

Figure 10.6A

DNA

Transcription

RNA

Protein

Translation

DNA RNA Protein

Close up on DNARNA: Transcription

RNApolymerase

RNA nucleotides

Direction of transcription

Template Strand of DNA

Newly made RNA

TC

AT C C A A T

T

GG

CC

AATTGGAT

G

U

C A U C C AA

U

Figure 10.9A

DNA RNA Protein– In the nucleus, the

DNA helix unzips• And RNA nucleotides

line up along one strand of the DNA, following the base pairing rules

– As the single-stranded messenger RNA (mRNA) peels away from the gene

• The DNA strands rejoin

RNApolymerase

RNA nucleotides

Direction of transcription

Template Strand of DNA

Newly made RNA

TC

AT C C A A TT

GG

CC

AATTGGAT

G

U

C A U C C AA

U

Figure 10.9A

transcription

DNA RNA Protein

• RNA pol binds to promoter

• Transcription of strand to mRNA

• Instructions now in mRNA

• RNA pol reaches terminator

RNA polymerase

DNA of gene

PromoterDNA Terminator

DNA

Area shownIn Figure 10.9A

GrowingRNA

Completed RNARNApolymerase

Figure 10.9B

DNA strand

Transcription

Translation

Polypeptide

RNA

Amino acid

Codon

A A A C C G G C A A A A

U U U G G C C G U U U U

Gene 1

Gene 2

Gene 3

DNA molecule

Figure 10.7

DNA RNA Protein

Figure 10.8A

UUC

UGUUGC

UGA Stop

Met or start

Phe

Leu

Leu

Ile

Val Ala

Thr

Pro

Ser

Asn

Lys

His

Gln

Asp

Glu

Ser

Arg

Arg

Gly

CysTyr

G

A

C

U

U C A G

Th

ird

bas

e

Second base

Fir

st b

ase

UUA

UUU

CUC

CUU

CUG

CUA

AUC

AUU

AUG

AUA

GUC

GUU

GUG

GUA

UCC

UCU

UCG

UCA

CCC

CCU

CCG

CCA

ACC

ACU

ACC

ACA

GCC

GCU

GCG

GCA

UAC

UAU

UAG Stop

UAA Stop

CAC

CAU

CAG

CAA

AAC

AAU

AAG

AAA

GAC

GAU

GAG

GAA

UGG Trp

CGC

CGU

CGG

CGA

AGC

AGU

AGG

AGA

GGC

GGU

GGG

GGA

U

C

A

G

U

C

A

G

U

C

A

G

U

C

A

G