Week 7 Lab: Cell-free systems
Protein synthesis requires transcription and translation
Transcription
eukaryotes or in cytoplasm in prokaryotes RNA polymerase DNA nucleotides to make RNA polymerase will bind promoter and in the space will
Translation
tRNA, amino acids and ribosomes, mRNA inside nucleas, splicing take introns and leave extrons
RBS (ribosome binding site) - attach to small subunit - mRNA to merge with small subunit tRNA will bind start codon (AUG/ ATG) (complementary to start codon) codons are 3 nucleotides EPA E P A are three sites of tRNA working on codons [exit, peptide, amino acid] bind to start, peptides growing protein on P site, then amino acid on site and leave ribosome
can happen outside of cells
TX transcription TL translation CFPS (Cell free protein synthesis)
Cell lysate
ribosomes for translations tRNA Initiation, transcription, and trasnslation factors Microsomes (membranes phospholipid bilayer)
Template
plasmid DNA (more stable) linear PCR
Supplements
Nucleotides amino acids ATP (transcription) GTP (translation)
buffer stabilize the pH
Prokaryotes transcription and translation can happen at the same time Eukaryotes separate (extrons and introns) you need specific machinery enzymes that will take out the introns
Cell free systems will give code sequence no need introns and extrons plasmid -coding sequence - use messenger RNA to produce insulin
Endosymbiotic theory (using mitochondria will be bactera - circular DNA too complex, use more energy keep mitochondria working)
-no time-consuming cloning steps required -reaction conditions can be fully controlled and modified -proteins that are toxic to cells can still be produced
Tx-TL system can be classified by the source of the cell extract
bacterial cell-free system E Coli eukaryotic yeast, mammalian, insect, plant
Insulin are made by disulfide bond make two polypeptide chains
Cell lysis and a lot of purification
Chromoproteins just have colors
GFP Green florescent protein requires blacklight
RFP
purification filters the protein you want
his-tag + protein of interest –> the tag will bind to another metal ion
Fusion protein | His-tag (histadine) | Ligand | Bead
Magnetic block
Today’s protocol:
GFP, RFP, mix Affinity Purification to isolate our samples Mixture –> will get separation
1 GFP 2 RFP 3 mix 4 mix