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6

I've found a nice review that has many details on plasmid replication in general, and several papers about pSC101 in detail, and I'll try to extract the key information from these papers. First of all your plasmid as an ori region that contains so called iteron: In many cases, the origin of replication contains directly repeated sequences, termed ...


5

There are some databases in which you can search for E.coli gene expression data: GenExpDB: E. coli Gene Expression Database Many Microbe Microarrays Database (M3D): A resource of microbial gene expression data Stanford MicroArray Database (use the search tool to find relevant organisms) Colombos (COLlection Of Microarrays for Bacterial OrganismS) ...


4

One is not normally required to serially dilute E. coli cultures for spectrophotometric measurements, at least in the experiments where the OD value is important. For most protein expression work, the consensus is to start the induction at OD 0.6, and for most chemically competent cells, the optimal OD ranges from 0.3 to 0.8 depending on the competency ...


3

E.coli can do that and in fact does this a lot in a commonly used bacterial medium: The popular LB Medium. This is composed of three components: Tryptone, a peptide mix made by digesting milk casein with the peptidase Trypsin (10g/l) Yeast extract, made by autolysis of the cells (5g/l) Sodium chloride (10g/l) The original formulation of Bertani from ...


1

In general, there is no need for a spacing between stop codon and terminator. They can be right next to each other. When transcribed, transcription terminator forms a hairpin-like structure which interacts with the RNA polymerase to stop the transcription. Usually, the upstream sequence will not interact with the terminator and it will be transcribed ...


1

You should dilute (not necessarily serially dilute) if: You are exceeding the concentration range detectable by the machine Scattering starts overwhelming absorption (at high cell densities scattering will overwhelm absorbance). In such cases you can use a turbidimeter. As such there is no issue of the law not holding true at certain limits of ...


1

Reading the optical density of a log phase microbial culture at a fixed wavelength approximates the Beer-Lambert law where A = ecl. This relationship is not linear as the Absorbance approaches 1.0 so at higher cell densities you will eventually underestimate the cell density of the culture. Likewise the law is not accurate below an Absorbance below ~ 0.05, ...



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