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Early Historical Milestones in CMB...
Between 1860-1925 two new areas of biology evolve into CMB… 1. Biochemistry... isolation & chemical characterization cell substances... synthesis of 1st natural biological product in lab... from urine &/or oxalic acid from spinach UREA 1828 Freiderich Wohler 1st macromolecule isolation free of cell... fibrous, acid precipitate = protein 1838 Gerhardus Mulder isolation of nuclein from from nuclei of white blood cells & sperm of Salmon 1869 Friedrich Miescher 1st cell free yeast extracts that convert glucose --> alcohol (fermentation) 1897 Eduard Buchner structural makeup of molecules (peptide bond)... 16 of 22 amino acid discovered 1900's Emil Fischer 2. Genetics... study of inheritance/characters in plants & animals... dominant/recessive; dihybrid crosses; value was quantitative approach 1865 G. Mendel [Mendel Web] chromosomal theory of inheritance (Meiosis matches Mendel) 1902 SUTTON & BOVERI "biochemical genetics" alkaptonuria- mutations = defective proteins 1902 Archibold GARROD coins term GENE + concepts phenotype & genotype 1909 Wilhelm JOHANNSEN chromosome linkage & mapping (Drosophilia) 1911-1920's T.H.Morgan (paper) & Sturtevant & Bridges 3. Molecular Genetics... isolation & chemical characterization cell substances... between 1925 to 1965 - Cell & Molecular Biology comes of age... period of discovery of chemical nature of gene & merging of biochemistry & genetics transforming principle (genetic agent causes pneumonia) 1928 Fred Griffith "one gene = one enzyme" 1941 G.Beadle & E. Tatum proteases don't alter gene transformation, but DNAses inactivate transformation, thus DNA is genetic material. 1st use of enzymes to test for active biological activity 1944 Avery, MacLeod & McCarty
jumping genes (transposons)
1944 -
Barbara
McClintock
base complimentarity amounts of bases A = T and G = C
1950
Erwin
Chargaffexperiments using 32P establish DNA as genetic material 1952 Alfred Hershey bio & Martha Chase 4. Cell & Molecular Biology... integration of molecular structure & cell function... between 1950-1990 - Birth of Modern CMB and Structural Biology... NHGRI Dynamic History Timeline & NHGRI Timeline Landmarks graphic
Foundations of Modern Cell & Molecular Biology,
i.e,
Bil 255
n
1953
to
2007
is the dawn of the modern
Molecular Cell Biology age
& is the content of Biology 255
some personal relevance...
my mother (nee 1906): saw advent of auto, airplane, radio, T.V., man on the moon...
me
(1943): heart transplants
(who
was 1st ?),
rise of antibiotics,
Rover on
Mars, DNA & transgenic animals, artificial genes & manipulation, cloning, human genome... CMB is part of our modern popular culture - Movies: Jurassic Park & Species-I
to reiterate...
The aim of Modern
CMB is to interpret the
What
fundamental questions
does
CMB ask
? How did life originate ? How does life beget life ? How does an individual (plant-animal) develop for a fertilized egg/seed?
What is progression from individual
molecules with the deciphering of DNA and our understanding of the Central Dogma... CMB gave us... the Central Dogma of Molecular Biology DNA --> RNA --> Protein mcb fig 4.1*
¨ Early
origin & evolution of cells must have
been
the result of those cells which
had
developed
self replicating molecules (RNA?)...
& thus had a better fit and likely were selected for evolutionary survival... " Life begets Life " - is now seen at the molecular level, is seen as the faithful replication of DNA... Development - pre-programmed unfurling of an organism’s genomic DNA; it is what underlies the growth of all organisms...
Reasons why we should...
Study CMB :
n
It is a Core Knowledge Area of Biology...
...
is
needed to understand the CELL
as the
unit of life,
... to learn those
properties common
to ALL eukaryotic cells.
by some
guesstimates :
between
2 million & 100 million
different
species
of organisms;
and each species has many different types of cells...
adult human body
has some
210 distinct cell types
with some 60 trillion total cells...
CMB asks...
what do all these cells have
in common...
What
cells types will we be looking at?
[see pg 25 - 28]*
[a freshman review of Prokaryote, Eukaryote, & Virus]
µ
Model Organisms*
cheap, plentiful, prolific reproducers, with simple genome
and common attributes & unique properties for practical research analysis: cell & molecular biology's research model organisms include:
Bacteriophages - a virus that infects bacteria; today used as cloning
vectors
Escheriichia coli - bacteria common to the human colon; molecular work horse [database]
Giardia - a primitive eukaryotic
cell,
an anaerobic protozoan cell with 2 nuclei
[Giardiasis]
other
eukaryotic
models include:
single celled - Saccharomyces cerevisiae - yeast [ pic ] plants - mustard plants Arabidopsis thaliana [ pic ] nematode - Caenorhabditis elegans [ 2002 Nobel ] animals - fruit fly Drosophilia melangaster [Mickey] mouse - Mus musculus - common house mouse & its genome Single cell culture models model systems for genetic & embryonic development research grown in the lab... Hela cells (pic + pic) - (George & Margaret Gey at JHU) human - fibroblast (connective tissue cells easily grown in tissue culture)
Cell & Molecular Biology
is about
energy &
reactivity,
movement
&
change,
action
&
reaction;
CMB
"
CMB... is
the practice of Biochemistry without a license "
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