DNA structure and analysis I (KCSPK 10) Genetic material - historic perspectives
DNA structure and analysis Proteins vs. DNA as genetic material: why were proteins
initially favored?
Introduction
Quantity of protein vs. DNA in the cell
Genetic information?
Levene’s tetranucleotide hypothesis
Both proteins and DNA in chromosomes
Fields of research at the
How does DNA serve as the genetic basis for life
time
processes?
1944 – Avery et al.
In this chapter
1927 – Griffith’s transformation
Proof that DNA is the genetic material of bacteria
The complex structure of DNA 1952 – Hershey-Chase
Analytic techniques
Properties of genetic material
Replication: the process of mitosis and meiosis
Storage of information: storing the complete DNA
component vs. gene expression Griffith’s experiment
Expression of stored information: the “central
Streptococcus Live
dogma of molecular genetics”
pneumoniae
Variation through mutation (gametes)
Virulent and
avirulent strains
“Transforming Live
principle”
Dead
Virulent strain – acute IIIS + live
infections IIRhigh
with =
mortality live IIIS
Avirulent strain – mild infection or no symptoms
, Frederick Griffith – 1927 Bacterial transformation: DNA is the “transforming
bacterial pneumonia “transforming principle”
principle”
Destroy proteins,
RNA, and DNA
(independently) to
check if
transformation
occurs in their
absence
Avery et al
DNA as genetic material
DNA is the Radioact
1944 – Avery et al: prove DNA to be the “transforming DNA
“transforming principle
Oswald Avery, Colin MacLeod, and Maclyn
McCarty DNAse RNAse
4. 3. RNA 2. 1. contro
DNA Protein for DNA l
1952 – Hershey-Chase: more support
hypothesis – phage T2 experiments
DNA structure and analysis Proteins vs. DNA as genetic material: why were proteins
initially favored?
Introduction
Quantity of protein vs. DNA in the cell
Genetic information?
Levene’s tetranucleotide hypothesis
Both proteins and DNA in chromosomes
Fields of research at the
How does DNA serve as the genetic basis for life
time
processes?
1944 – Avery et al.
In this chapter
1927 – Griffith’s transformation
Proof that DNA is the genetic material of bacteria
The complex structure of DNA 1952 – Hershey-Chase
Analytic techniques
Properties of genetic material
Replication: the process of mitosis and meiosis
Storage of information: storing the complete DNA
component vs. gene expression Griffith’s experiment
Expression of stored information: the “central
Streptococcus Live
dogma of molecular genetics”
pneumoniae
Variation through mutation (gametes)
Virulent and
avirulent strains
“Transforming Live
principle”
Dead
Virulent strain – acute IIIS + live
infections IIRhigh
with =
mortality live IIIS
Avirulent strain – mild infection or no symptoms
, Frederick Griffith – 1927 Bacterial transformation: DNA is the “transforming
bacterial pneumonia “transforming principle”
principle”
Destroy proteins,
RNA, and DNA
(independently) to
check if
transformation
occurs in their
absence
Avery et al
DNA as genetic material
DNA is the Radioact
1944 – Avery et al: prove DNA to be the “transforming DNA
“transforming principle
Oswald Avery, Colin MacLeod, and Maclyn
McCarty DNAse RNAse
4. 3. RNA 2. 1. contro
DNA Protein for DNA l
1952 – Hershey-Chase: more support
hypothesis – phage T2 experiments
