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Jan
19
comment Multi-modal distribution for gene expression data
@nico's point is spot on, we can't answer until we know more. Also, should I intepret your question to mean you are not interested in bimodal (i.e exactly 2 modes) distributions? Those are usually easier to explain, have more concrete examples, and should generalize to a multimodal case. But if you are not interested in bimodality please make that clear.
Jan
16
answered Do bacteria with multiple flagella move faster than bacteria with a single flagella?
Jan
16
comment An Example of Building something from scratch in small steps
I also disagree with the claim that "every step adds usefulness." Population genetics has taught us that there are ways for alleles to increase in frequency without necessarily being more fit--things like neutral drift. Complexity may arise by accumulation of fitness-neutral mutations. What's really interesting is that this neutral drift may allow formerly deleterious mutations to become very beneficial; without it "useful" change could not have occurred. Such "evolutionary epistasis" has been interestingly demonstrated at the protein level with the evolution of estrogen/steroid receptors.
Jan
16
revised How is the reflectance spectrum of solids measured?
Added section on additional spectroscopic technique based on a suggestion in a comment.
Jan
16
comment How is the reflectance spectrum of solids measured?
@ChrisStronks fair point. I wasn't really aware how spectrophotometers are actually built/implemented, more just the conceptual idea behind them. I can edit the answer to reflect this.
Jan
13
comment Does antibody staining / immunolabeling block or inhibit protein function?
Also, the assay for functionality completely depends on the protein you're testing. Assuming you have an in vitro assay for your protein's function, you could try performing the assay at a given protein concentration with varying concentration of antibody to see if there is a significant effect on activity in vitro. It might not correlate well in vivo, but it is a start.
Jan
13
answered How is the reflectance spectrum of solids measured?
Jan
13
comment Typical in-vivo protein concentration
Hard to find data for eukaryotes. For E coli some of these things have been measured and rough numbers have been made. I recommend the BioNumbers database as a great starting place: bionumbers.hms.harvard.edu/default.aspx . In particular, look up the (famous) table linked to by Bio Number ID 102990. It lists that at exponential phase E coli has about $2.35\times10^6$ protein molecules of 1850 types, so about 1270 copies of each protein. E coli is about 1 $\mu$m$^3$, so that's a concentration of about 20$\mu$M per protein if my math is right. But that's bacteria which are very different.
Nov
25
comment Crude oil contamination hazard
I appreciate the collection of information from many different sites. I think this would be most helpful to the author if you synthesized the information a little more, presented some main takeaway points? Also, I noticed you have copy-pasted a number of paragraphs directly from the different links. While it's good you show your sources, you might want to look at the guidelines on referencing and see if you can make these quotes conform better to standards: biology.stackexchange.com/help/referencing. In particular, I think you could make it clear which parts are direct quotes.
Nov
25
comment Statistics on energy consumption breakdown per biological functions across organisms?
Awesome. You're right that the categorization may be difficult, but I absolutely see the potential interest. Narrowing down the question like this to the fraction of energy consumption in signal transduction already makes it more tractable. Complementary to your question about energy consumption, are you aware of the bioinformatic research on genome reduction in parasites? I think interesting trends can be observed comparing the loss of signal transduction proteins compared to other protein groups. An example of this type of analysis: ijsb.sgmjournals.org/content/54/6/1937.full
Nov
25
comment Statistics on energy consumption breakdown per biological functions across organisms?
In bacteria this has been studied in great detail for cells growing in steady balanced exponential growth. The classic reference work for this is Physiology of the Bacterial Cell by Neidhardt, Ingraham, and Schaechter: amazon.com/Physiology-Bacterial-Cell-Molecular-Approach/dp/… . Over the course of a few chapters they painstakingly identify how many ATP molecules are consumed for each process, from replication, transcription, translation, cell wall synthesis, etc, over the course of a single cell cycle. Not sure if this has been done in eukaryotes.
Nov
25
comment Statistics on energy consumption breakdown per biological functions across organisms?
Out of curiosity, what do you mean by information processing? I can see this being used in several ways in biology: transcription/translation, signal transduction, you might even make an argument that some forms of enzyme binding kinetics are information processing (identifying the correct input from a sea of possible inputs). Of course also these numbers would only be meaningful in very specified and constrained environments.
Nov
25
comment B cell receptor editing
When I look at Wikipedia I can't find definitions of kappa versus lambda light chain. In the interest of making this question more broadly useful, would you mind adding some more definitions to your post? It might also help someone who is less of an expert do the requisite research to answer your question.
Nov
21
reviewed Approve Quetiapine tolerance
Nov
19
reviewed Approve Why does a cockroach not die even after decapitation?
Nov
19
reviewed Approve What are the “stars” we see after a bump on the head?
Nov
19
revised Which virus capsids consist of only one type of capsid protein?
added some minor clarifying phrases.
Nov
19
answered Which virus capsids consist of only one type of capsid protein?
Nov
5
awarded  Yearling
Oct
18
comment Mutation-Selection-Drift Equilibrium
I think this paper might be relevant. From what I can see they derive an analytical approx for deleterious allele frequency in MSD equilibrium.ncbi.nlm.nih.gov/pmc/articles/PMC1894624