[1S] UNIT 1.2 History of Molecular Biology Flashcards
ORIGINS OF MOLECULAR BIOLOGY
T/F: Arose from the convergence of work by geneticists, physicists and structural chemists on the nature of inheritance.
T
ORIGINS OF MOLECULAR BIOLOGY
T/F: Molecular diagnostics is relatively a young science tracing back from the 1930s to 1940s and becoming institutionalized on the 1950s and 1960s.
F; Molecular biology
The study of biomolecules and biomolecular mechanisms that occur in living organisms.
Molecular Biology
Mainly focused on the structure and function of gene: molecular nature of the gene, gene replication, mutation and repair and gene expression
Molecular Biology
The study of molecular basis of life such as biochemical processes that control information flow through biochemical signalling and the flow of chemical energy through metabolism.
Biochemistry
Deals with the structures and functions of cellular components such as proteins, carbohydrates, lipids and nucleic acids.
Biochemistry
T/F: Molecular biology and biochemistry are closely related disciplines. Initially, biochemistry focuses on proteins and enzymes until it includes nucleic acids and the molecular mechanisms by which genetic information from DNA results in the processes of life.
T
The term “molecular biology” was coined by _______ ______ of the Rockefeller Foundation in 1938 – in recognition of the importance of new physical and structural chemical approaches to biology.
Warren Weaver
_______ _______ work on transmission of inheritable traits – Law of Aggregation & Law of Independent Assortment
Gregor Mendel
Father of Modern Genetics
Gregor Mendel
Discovered “nuclein” a new molecule from the cell nucleus and believed that proteins were the molecules of heredity, in 1869.
Friedrich Miescher
previously thought the transforming principle is now called the DNA.
Nuclein
In 1928, ________ ________ was studying two strains of Streptococcus pneumoniae that varied dramatically in both their appearance and their virulence. Specifically, the highly virulent S strain had a smooth capsule (polysaccharide), while the nonvirulent R strain lacked a capsule.
Frederick Griffith
found that mice inoculated with either the heat-killed virulent bacteria or the living avirulent bacteria remained free of infection, but mice inoculated with a mixture of both became infected and died.
TRANSFORMING PRINCIPLE: Frederick Griffith
hypothesized that a chemical component from the virulent S cells had somehow transformed the R cells into the more virulent S form
TRANSFORMING PRINCIPLE: Frederick Griffith
In 1944, ________, _______, _______ used a process of elimination to identify the transforming principle.
Oswald Avery, Colin McLeod and Maclyn McCarty
T/F: According to Griffith, DNA is the hereditary material. Thus, transformation cannot occur unless DNA is present.
F; Oswald Avery, Colin McLeod and Maclyn McCarty
DNA AS THE GENETIC MATERIAL
In 1952, they prove that DNA is the transforming principle and not protein using series of experiments involving T2 bacteriophages.
Alfred Hershey and Martha Chase
DNA AS THE GENETIC MATERIAL
are viruses that infect bacteria (T2 bacteriophage infects E. coli) and widely used for studying genetic transmission.
Bacteriophages
DNA AS THE GENETIC MATERIAL
Consists both of protein and DNA which can be selectively incorporated by radioactive isotopes for tracing of bacterial infection. (32-phosphate for DNA and 35-sulfur for protein).
T2 bacteriophage
The elucidation of the double helical nature of DNA must be attributed to the contributions of key scientists (______, _______, ______) including the X-ray crystallography done by _______ ________ & _________ _______.
Miescher, Levene and Chargaff
Rosalind Franklin and Raymond Gosling
Discover the order of the three major components of a single nucleotide (phosphate-sugar-base), carbohydrate component of RNA (ribose), carbohydrate component of DNA (deoxyribose)
Phoebus Levene
first to correctly identify the way RNA and DNA molecules are put together
Phoebus Levene
● the nucleotide composition of DNA varies among species
● almost all DNA-no matter what organism or tissue type it comes from maintains certain properties even composition varies (“Chargaff Rules”)
● In particular: A = T; C = G (A + G) = (C + T)
Erwin Chargaff
In 1951, she was offered a 3-year research scholarship to help set-up and improve the X-ray Crystallography unit at King’s College.
Rosalind Franklin
In 1951, she was offered a 3-year research scholarship to help set-up and improve the X-ray Crystallography unit at King’s College.
Rosalind Franklin
Working with a student, Raymond Gosling, they were able to generate two sets of high-resolution photos of crystallized DNA fibers
Rosalind Franklin
Deduced that basic dimensions of DNA strands, and that the phosphates were on the outside, probably hinting like a helical structure.
Rosalind Franklin
PUTTING THE EVIDENCE TOGETHER
They contributed to Watson and Crick’s derivation of the 3-dimensional, double helical model of the structure of DNA.
Rosalind Franklin, Raymond Gosling and Maurice Wilkins
PUTTING THE EVIDENCE TOGETHER
The unsung hero of the double helix who recruited Franklin
John Randall
SEMICONSERVATIVE DNA REPLICATION
They provided the experimental proof of semiconservative replication by inventing “density gradient centrifugation” – which uses centrifugal force to separate molecules based on densities.
Matthew Meselson and Franklin Stahl
In 1958, he enunciated the concept of “Central Dogma of Molecular Biology” based on their findings of DNA structure
Francis Crick
T/F: The protein synthesis process is reversible back to DNA or RNA
F; irreversible
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLBIO
He utilized fruit flies, Drosophila melanogaster, as model organisms to study the interaction and hereditary process between the gene and the chromosomes.
Thomas Hunt Morgan
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLBIO
The first person to link the inheritance of a specific trait with a particular chromosome (Chromosome theory).
Thomas Hunt Morgan
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLBIO
He studied the hereditary characteristics of fruit flies, and in 1927, discovered that the number of genetic mutations observed in fruit flies increased when exposed to x-rays.
Hermann J. Muller
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
Her maize breeding experiments provided the first detailed description of transposable elements (transposons). These mobile elements are referred to as “jumping genes”.
Barbara McClintock
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
Transfer one genetic material to another
Transposons / Transposable Elements
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
He isolated and discovered DNA polymerase I and showed that life can be made in test tube.
Arthur Kornberg
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
They shared the Nobel Prize for Physiology or Medicine – ______ for enzymatic synthesis of DNA and ______ for enzymatic synthesis or RNA.
Arthur Kornberg
Severo Ochoa
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
They hypothesized the existence of an intermediary between DNA and its protein products called messenger RNA.
Francois Jacob, Andrew Lwoff & Jacques Monod
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
They also discovered bacterial operons which are protein-binding regulatory sequences.
Francois Jacob, Andrew Lwoff & Jacques Monod
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
The group of scientists who first unlocked the genetic code in 1963 and 1966.
Marshall Nirenberg, Har Gobind Khorana, Philip Leder & Heinrich Matthaei
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
He finished and has trained organic chemistry as profession but his interests in living things led him to discover the transfer RNA.
Robert Holley
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
Restriction endonucleases technology in 1969, 1970
Matthew Meselson, Werner Asber, Daniel Nathans & Hamilton Smith
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
They developed Recombinant DNA technology and pioneered research on gene manipulations
Paul Berg, Stanley Cohen, Herbert Boyer
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
● First to pioneer DNA sequencing
● Utilized to detect mutations in the genetic sequencing
● Using dideoxynucleotide forms; chain termination sequencing technique
Frederick Sanger
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
Discovery of reverse transcriptase enzyme and study tumor virus activity
David Baltimore, Renato Dulbeco & Howard
Temin
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
Phylogenetic taxonomy of 16s rRNA resulting to the “tree of life”. He discovered the third domain of life, the archae.
Carl Woese
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
In 1977, the ________ DNA sequencing was introduced. In 1978, ______ proposes existence of introns and exons; and in 1986, he proposes the RNA world as the origins of life.
Maxam- Gilbert (Walter Gilbert & Allan Maxam)
Walter Gilbert
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
1981: Nucleic acid-protein complexes
Aaron Klug
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
1986: RNA as enzymes (Ribozymes)
Thomas Cech Sidney Altman
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
1989: spearheaded the Human Genome Project – a 13-year international effort to discover the 20,000 to 25,000 human genes and uncover the sequence of the 3 billion DNA subunits contained in human chromosomes
James Watson
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
1989: Knockout mice technique
Mario Capecchi
Martin Evans
Oliver Smithies
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
1993: Polymerase chain reaction (PCR)
Kary Mullis
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
1996: Cloning of “Dolly” the sheep by nuclear transfer from cultured cell line
Keith Campbell
Ian Wilmut
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
1998: RNA interference (RNAi)
Craig Mello
Andrew Fire
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
2000: Crystal structure of the ribosome
Thomas Steitz
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
2011: CRISPR/Cas9 gene editing mechanism
Emmanuelle Charpentier
Jennifer Anne Doudna
NOTABLE CONTRIBUTIONS IN THE FIELD OF MOLECULAR BIOLOGY
2011: CRISPR/Cas9 gene editing mechanism
Emmanuelle Charpentier
Jennifer Anne Doudna
Figured out the structure and building blocks of DNA
Phoebus Levene
