Lesson 5 - BIO 30

quantitative geneticist

fisher

Two view points about genes

hypothetical entity, chemical compound

characteristics of genetic material according to Muller

duplication with high fidelity, stable molecular structure, faithful inheritance of mutation, information storage, transmission, and translation

greek word meaning “of first importance”

proteios

thought to be the most important molecule.

protein

while characterizing proteins from pus cells, isolated a molecule from the nucleus and called it “nuclein”

Friedrich Miescher

discovered that the most obvious cellular component of the cell is the nucleus

Ernst Haeckel

using staining technique to study karyokinesis of ovum. important nuclear element handed from cell to cell: DNA

Edmund Wilson

transformation experiment using Streptococcus pneumoniae

Frederick Griffith

avirulent (R) strain was transformed to virulent (S), declared the presence of transforming principle

Frederick Griffith

identified the transforming principle (TP) as DNA

Avery, MacLeod, McCarty

proved that DNA is the genetic material of the bacterial viruses (phages)

Alfred Hershey and Martha Chase

label of dna

p32

label of protein coat

s35

famous blender experiment which separated phages from bacteria after infection

Alfred Hershey and Martha Chase

performed transduction experiment in Salmonella typhimurium

zinder, lederberg

Worked on X-ray diffraction of DNA

Maurice Wilkins

Elucidation of the structure of the DNA

Francis Crick and James Watson

expert on X-ray diffraction technique

Rosalind Franklin

triple helix DNA

Linus Pauling

nucleotides are flat, one on top of another, possibility of A=T, C=G pairing

John Griffith

purine-pyrimidine ratio 1:1

Erwin Chargaff

H in the bases can change its position, possibility for H bonding

Jerry Donohue

features of dna

2 polynucleotide strands, anti-parallel strands, ATCG specific pairing, helical coil, 2-deoxy-d-ribose sugar

Evidences to show that DNA is the genetic material

constancy of dna in all diploid tissue, haploid cell has half the amount of dna, doubling of dna content in s phase, extra set of chromosome has higher dna content, parallelism of uv absorption with mutation rate, transformation and transduction, Production of new viral particles, rna content causes infection not protein coat

rna structure

1 polynucleotide strand, d-ribose sugar, uracil instead of thymine

semi-conservative model, centrifugation in cesium chloride of E. coli

Matthew Meselson and Franklin Stahl

where does initiation start?

ori-site

helix unwinding proteins that breaks hydrogen bonds

helicase

basic unit of chromatin

nucleosome

nucleosome consists of?

h2a, h2b, h3, h4, molecule of dna wound twice

how one nucleosome is connected to another

linker dna

causes chromatin folding

h1

hollow tube for further packaging

solenoid

nucleotide consists of?

phosphate group, pentose sugar, nitrogen base

nitrogen base with sugar

nucleoside

distance between 2 base pairs?

3.4 angstroms

keeps the strands from reannealing

single strand binding proteins

relaxes tension at the fork

dna gyrase

adds RNA primers for elongation

primase

adds nucleotide triphosphates complementary to the dna template from 5’ to 3’

dna polymerase iii

the lagging strand produces?

okazaki fragments

proofreads dna molecule and removes primers

dna polymerase i

seals nicks/breaks in the dna segments

ligase

levels of chromatin packing

nucleosome - beads on a string - 30 nm chromatin fiber - looped domains - chromosome

helicase + primase

primosome

consists of DNA Polymerase III with two catalytic cores and primosome

replisome