Cramm Flashcards
Griffith
4 mice: S, R, S heat killed, S heat killed and R
-> transforming principle: molecules released when S cells killed=> transform R cells to virulent S form
(Permanent and heritable)
Avery MacLeod and McCarth
RNAse, PROTEase, DNAse… in cytoplasm. Of heat killed S cells (protein, RNA an DNA)… only DNAse had no change so DNA is the transformation molecule
Hershey and Chase
Infection, Blending and Centrifigutation
35S (protein)=> in detached bacteriophage (parent) but not in progeny bacteriophage (kid)
32P (DNA)=> found in detached bacteriophage(parent) AND found in progeny bacteriophage (kid)
So DNA is inheritable
Rosalind Franklin
X-ray diffraction
Concluded:cyclin drivel DNA and stacked and X shape diffraction
Watson and Crick
-> double helix (phosphate pentose backbone) (from Franklin)
-> antiparallel (3-5, 5-3)
-> Purine always pairs with Pyrimidine (from chargaff rule)
-> backbone is hydrophilic, bases hydrophobic
->semiconservative replication
-> parental strand unwind by breaking H bond
Edwin Chargaff
- % purines=% pyrimidines
- A%=T%, C%=G%
Meselson and Stahl
DNA banding…
1.15 N medium in 14 N medium (centrifuge 1)=> 100% 15N
2. replication 1 (centrifuge)=> 50, 50
3. Replication 2 (centrifuge)=>2 of them 100% daughter, 2 of them daughter and parental mix
DNA repair
- DNA poly proofreading… DNA pol III 3->5 exonuclease to remove nucleotide…. DNA pol III 5->3 new replacement nucleotide base
- MMR (DNA mismatch repair)… recognized by MutS/L, MutH endocnuclease picks hitman target… Exo1 5-3 endonuclease removes region… DNA pol III replacement nucleotide REGION… Ligase seals
DNA replication eukaryotic
- DNA helicase unwind double helix and ssBs (single stranded binding protein) prevent reannealing
- RNA primase (puts RNA primer)
- Topoisomerase (prevent twisting)
4.Sliding clamp attaches=> DNA pol III=> add n.b. - DNA Pol I removes RNA primer of Okazaki fragment and fill gap with dNTP
- DNA ligase… glues pieces together
(Stop at end of chromosome)
Read: 3->5
Synthesize: 5->3
Leading… continuous and toward fork
Lagging… chopped and away from fork
DNA replication bacteria
- Initiation: unwind and sep 2 temp. @ oriC (origin of replication site)
- Elongation: simultaneous synthesis of 2 new DNA strands from template by DNA poly
- Temrination: DNA rep. Stop at termination site
RNA B4 DNA
-> RNA is less stable
-> RNA is ss
-> RNA has enzymatic activity
->ribozyme can self synthesize and make RNA
Beadle and Tatum
1-gene-1-enzyme
Gene code enzyme and ricochet till essential nutrient
-> mutation can block metabolic pathway cause organism is auxotroph
-> if add nutrient after arrow of mutation then essential nutrient made… if b4 then will be inhibited by mutation
Life cycle SARS CoV2
- Bind
- Fuse viral RNA into host cell
3.RNA-> DNA by reverse transcriptase - Viral DNA to DNA of host and integrate by Integrase
- Replication
6.transcription
7.translation - Maturation and protease (breakup polyprotein into pieces and viral cell matures/assembles)
9.lyse and is virulent
Which structure is RNA (primary, sec, tert, quart??)
Secondary
Structure and fxn of gene
-promoter (DNA+TATA box-specify were transcription begin) at 5’ end/upstream of nontemplate/coding strand
-promoter is recognized and bound by transcriptional machinery (RNA poly and transcription factors)… initiate transcription
-transcriptional unit is part of gene copied into RNA