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1920
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location United Kingdom
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From the era before Sanger sequencing was invented.


Apr
6
answered What are mast cell membranes made out of?
Apr
4
comment Is there any documented case in which floating substances led to the introduction of a new species?
But not including actual sea-going vessels?
Apr
3
revised Can excessive carbonated drink consumption lead to elevated red blood cell levels?
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Apr
3
comment What is the energy consumption of the brain?
I'm not denying that brain activity will require more energy (to restore membrane potential), I'm just dubious that it will be a very big difference (the brain is active during sleep too). I await an answer that provides evidence about this.
Apr
3
answered What is the energy consumption of the brain?
Apr
3
answered Can excessive carbonated drink consumption lead to elevated red blood cell levels?
Apr
2
comment How can a YAC be screened against a cDNA library and a cosmid library of genomic DNA to find a gene?
@Superbest - hybridisation of probe to clone will occur if there is shared sequence. The fact that there might be small differences in sequence (alleles) or missing sequence (no introns in cDNA clone) will be irrelevant. Before transcriptomics this was the standard way to relate genomic DNA mapping to information about transcripts coming from cDNA cloning.
Apr
2
answered How can a YAC be screened against a cDNA library and a cosmid library of genomic DNA to find a gene?
Apr
1
comment What are the roles of guanidine-HCl and ethanol in binding of DNA to silica?
There is an excellent discussion of this in: Melzak et al. (1996) Driving forces for DNA adsorption to silica in perchlorate solutions. J. Colloid Interface Sci. 181: 635 - 644 I've skimmed the paper, and I'm beginning to understand it, but I don't feel up to actually answering the question yet.
Apr
1
revised What are the roles of guanidine-HCl and ethanol in binding of DNA to silica?
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Apr
1
revised How do Gram + bacteria use a proton gradient for F-type ATPase?
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Apr
1
comment How do Gram + bacteria use a proton gradient for F-type ATPase?
In response to your first comment, protons would move up a proton concentration gradient if the membrane potential was favourable, until the chemical and electrical potentials were balanced.
Mar
31
answered How do Gram + bacteria use a proton gradient for F-type ATPase?
Mar
31
comment How do Gram + bacteria use a proton gradient for F-type ATPase?
Don't have an answer, but it seems to me that given that the Gram negative outer membrane is stuffed full of porins, there is no barrier to proton loss in this case either.
Mar
30
comment Cloning a gene of an organism with an nonsequenced genome
Do you want to clone the gene ( genomic DNA) or a copy of the mRNA (cDNA)? (I imagine it's the latter.)
Mar
30
revised Significance of lipids in biological membranes…?
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Mar
30
revised Significance of lipids in biological membranes…?
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Mar
30
answered How do ants spontaneously grow wings?
Mar
29
answered Significance of lipids in biological membranes…?
Mar
29
comment E coli cotransformation efficiency
Nothing to back this up with so just a comment: my understanding is that the cells which are competent take up a lot of DNA, so cotransformation is easy to achieve as long as you can select for both plasmids (if they have replication/segregation features from the same incompatibility group they will segregate rapidly). I once did a Tn5 mutagenesis experiment which required propagating the plasmid in a Tn5 strain, preparing plasmid, transforming a recipient at high DNA input and selecting for kanamycin resistance. Many transformants contained more than one plasmid but they resolved easily.