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3

I see no reason why not. Just to make sure, I decided to test. I ran a search on all human proteins (using the UniProt flat file) for all possible dipeptide combinations of the 20 standard amino acids (selenocysteine is also present in humans but only in 22--or so, depending on how you count them--proteins, so I wouldn't expect all possible sec-containing ...


2

You might be interested in the Foot and Mouth Disease 2A Peptide, a self-cleaving peptide sequence that can be inserted in between two proteins. The proteins are translated as one sequence, but cleaved at the 2A peptide to form 2 proteins. If I'm reading the source right, they used 4 genes in a row with 2A peptides between them. The 2A peptide has the ...


1

Consider the phenomenon of zygotic induction, as originally observed by Art Pardee, Francois Jacob, and Jacques Monod (sometimes called the "PaJaMo", or "PaJaMa" experiment): regulation of a repressed promoter can be affected by the copy number of the promoter in the cell. Put another way, if the copy number of the lac operator in the cell is high enough to ...


1

Galvinoxyl is a free radical, which means it has an unpaired electron that can be detected with EPR. Antioxidants reduce the radical, which is then not detectable in the EPR anymore as it doesn't have an unpaired electron. What you need the EPR for in the assay is to determine how much of the galvinoxyl is still a radical. Paramagnetic molecules like ...


-1

Phenotype is the physical result that one sees that is the outcome of genetic makeup. Genotype is the code that is written in the DNA (or RNA if you are a retrovirus). Enzyme composition in the cell, hair color, proclivity towards certain diseases; pretty much everything is a product of genoptype. There are some other factors in the environment that affect ...


0

There is at least one known case where both the DNA and RNA versions of the same aptamer sequence bind the same target (Lauhon and Szostak, 1995). But you can't generalize this, there are two differences in structure between RNA and DNA, the Uracil/Thymine change and the missing 2'-OH in DNA. Those differences can affect the binding and overall structure of ...


-1

Aptamers are single-stranded sequences that bind to proteins or other molecular partners. Obviously, ssDNA and ssRNA have very different (in general) binding partners. E.g. DNA is interacting with transcription factors, RNA polymerase, histones etc, while RNA is interacting with ribosomes, reverse transcriptase and others. So, shortly, it is more likely ...


6

Parallel DNA helix can exist and this has been observed experimentally. However these structures are stabilized by Hoogsteen type base pairing [1,2] and not the usual Watson-Crick type pairing because the parallel conformation does not allow the latter (See the figure below). This elongates the hydrogen bonds and also causes a loss of one hydrogen bond ...


-3

This is more chemistry than Biology. Both strands of DNA are 5' to 3' direction. Why so? because the direction is determined in terms of the direction in which purine or pyrimidine bases are added. The four bases that exist in DNA are Adenine, Guanine, Thymine and Cytosine. They are referenced under Purine and Pyrimidine links posted above. This molecule ...


3

Sure that will work, or gel purify the ss cDNA, or treat the rxn with alkali to degrade RNA. The real questions in my mind are: What will you use as a primer for the RT? What are you going to do with this pure ss cDNA? If you already have the target cloned (how else would you transcribe it in vitro?), then why not just do a linear PCR where you cut the ...


2

Basically, they engineered a vector which, when transfected to E. coli, produces transcripts of -and thus proteins to- a fusion gene which produces these transmembrane α helices conjugated to the staphylococcal nuclease. In other words, the E. coli are just factories for producing proteins: Expression, Extraction, and Purification of SN/GpA - For high ...


1

If there is a such a site, I have never encountered it. Since you say you have the genomic coordinates for each primer it seems to me like all you need is a list of the genomic coordinates of every transcribed exon in the human genome. Assuming that is correct then you are in luck because such lists do exist in the form of a GFF3 file. You should be able to ...


0

In my own research I've found that the amount of PCR product increased as I increased the cycles to 50 times. This was for a single pair of primers used to amplify genomic DNA extracted with a particular kit as doesn't apply to other reactions I've done. What some people seem to forget is that the PCR products don't necessarily double at each cycle at any ...


2

From the abstract of the linked article (Guttman, 2002): We used an in vivo genetic screen to identify 13 effectors [...]. Although sharing little overall homology, the amino-terminal regions of these effectors had strikingly similar amino acid compositions. And from the body: The screen relied on the type III secretion signal and the endogenous ...



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