The scientific study of chemical processes in living organisms, including, but not limited to, living matter.
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39 views
Do proteins bind to carbon? If so how?
Can someone explain me whether a protein (like an antibody) would bind to carbon? The carbon arises due to electron beam induced deposition of Polyethylglycol (PEG). The carbon molecules that arise ...
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79 views
Can silicon-based life exist? [closed]
My friend is just trying to convince me, that silica based life could potentially exist somewhere
Carl Sagan regarded the belief that only carbon can support life as "Carbon Chauvinism" (the phrase ...
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30 views
PEG (polyethylene glycol) and ITO (indiumtinoxide)
The binding of proteins to an ITO surface can be prevented by coating it with PEG groups (polyethylene glycol). PEG-silane is used to create the coating.
can somebody help with:
*Why does PEG silane ...
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1answer
21 views
Plastic: Reputable Publications
I would just like some reputable textbooks and or publication companies that have extensive research on plastics, as, for example, dealing with life cycles of plastics, degradation factors, effect on ...
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21 views
What is the best way to disolve and consume Cysteine HCL Monohydrate powder?
If I mix Cysteine powder in Juice (something acidic maybe), does it remain at Cysteine?
It seems that it can oxidize into Cystine and loose some of its qualities. Veg-caps deliver the powder ...
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1answer
70 views
How to determine with at-home tools how much testosterone is present in blood safely?
so someone told me females don't have testosterone, and they are obviously wrong, as not only science, but peer testing, common sense, and general anatomy will disagree with females not having any ...
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1answer
35 views
Why do we need to incubate this system for 18 hours at 60 degrees Celsius?
I am conducting a bio-chemistry related experiment and I have been unable to understand a step which is commonly performed. The procedure that is confusing me is outlined in the supporting ...
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1answer
35 views
Does tolerance to alcohol affect blood/breath alcohol levels?
When blood / breath alcohol levels are taken to determine how intoxicated a person is, does it depend on their tolerance ?
i.e. If you had two people of identical age, weight, fitness, etc.
person ...
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79 views
Why do chalcogens (Group VI) stink so badly?
For more fun with Dr. Derek Lowe, see this for a primer: Things I Won't Work With - Carbon Diselenide. The short of it is that we carbon-based life forms generally like oxygen. However, move just one ...
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28 views
What Free Linux-Compatible Software Exists for the 3D Virtualisation of Biologic Proteins and Peptides? [closed]
What Free Linux-Compatible Software Exists for the 3D Virtualisation of Biologic Proteins and Peptides such as Receptors, Transporter Proteins and Peptides (e.g. $\beta$-endorphin)?
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34 views
Homemade preservative for natural aloe-vera gel?
I suppose this question can be extrapolated to food in general, but it is the case that I would like to know if there are any methods that would help me to keep the aloe gel fresh, i.e. avoiding it to ...
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1answer
88 views
Recreational drugs by half life
I am interested in the Biological Half Life of substances. In the previous wikipedia link, I've already found the half lives of common pharmaceutical products. I can't seem to find similar data for ...
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29 views
What metabolite intermediate will accumulate in a mammalian cell-free extracts capable of glycolysis if lactate dehydrogenase is inhibited?
I know the reaction proceeds as follows:
Pyruvate accepts the electrons from NADH to form lactate. What would be the intermediate in this reaction? Would it be NADH or NAD+?
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74 views
Is it possible to separate salt from food, or at least convert it into something that doesn't taste salty?
A couple months ago, one of my room mates accidentally used a cup of salt to make apple crumble. She asked if there was any way to separate it, probably because I had recently reduced the acidity of a ...
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1answer
97 views
What are the factors controlling the fate of post-adhesed volatile molecules of the olfactory epithelium?
What happens to volatile molecules that reach the main olfactory epithelium in the nasal cavity after they bind and the neural stimulus fades?
To what extent do such factors as receptor kinetics and ...
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20 views
Which mutated enzymes act as better drugs than their non-mutated form?
Is there an enzyme which is used as a drug (let it be called version $A$) and a mutated version of it ($M$), where the activity of $M$ was found to be higher than $A$?
Any references on such a case ...
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2answers
88 views
How can I control the oxygen in an erlenmeyer flask in a bioprocess?
I need to control oxygen in a erlenmeyer flask in a bioprocess. I need to remove overall oxygen in a erlenmeyer flask, and after I need to add oxygen in controlled amounts to a culture in a shaken ...
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29 views
Aflatoxin versus Benzene, permissible levels
Alfatoxin and benzene are carconogenic, and this is the major concern for low, chronic doses. They are regulated to the few parts per billion level in food. However, according to ...
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61 views
How is the time for a test tube in a centrifuge determined?
I came across some hairy math that's used for analytical centrifugation, mostly for things like determining the sedimentation rate for liquids.
However, what I don't understand is how someone ...
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1answer
56 views
Is formaldehyde a carbohydrate?
Formaldehyde has the formula CH2O, and the ratio of atoms in a simple carb is 1C:2H:1O. This fits the formula of formaldehyde. When I researched this, I found some sources saying that formaldehyde is ...
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35 views
Determine max of 2 parameter functions
I have 12 experimental tables with OD(substrate concentration, time), where OD is optical density and one table with $\mu$ (substrate), where $\mu$ is growth speed. OD and $\mu$ are functions.
The ...
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1answer
83 views
Why is tin (II) fluoride more effective in turning apatite into fluorapatite?
In more powerful toothpastes, like Crest Pro-Health, stannous fluoride is used in place of sodium fluoride.
According to Wikipedia:
Stannous fluoride converts the calcium mineral apatite into ...
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1answer
137 views
Why does milk flake?
While drinking milk (or better 'while seeing the milk I'm gonna drink') a question came up to my mind:
Why does the milk sometimes flake, even if not in contact with some other substances?
I guess ...
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1answer
338 views
Chemicals and killing bacteria question
Are there ways to compute what chemicals kill a give bacteria but not another given bacteria ?
Does that help much to make medication ?
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2answers
195 views
Why do lipids in a cell hydrolyze into glycerol and fatty acids?
Most Lipids in a cell have ester bonds (made up of glycerol and fatty acids).
I have learned in my chemistry class that we can hydrolyze an ester by simply adding water to it.
$$\cee{CH3COOCH2CH3 ...
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2answers
193 views
Cyanogenic glycosides and HCN
I'm researching cyanide for a biology project and noted that one of the largest sources of carbohydrates in the tropics is the cassava root -- which I previously researched as a food that contains a ...
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1answer
368 views
Why does menthol (e.g. peppermint) feel cool to the tongue?
Especially when drinking water after the fact, mint can give a sharp cold sensation inside one's mouth. What process causes the sensation to occur?
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1answer
66 views
What is the timescale of disulfide bond formation?
What is the timescale of disulfide bond formation in a given protein? What influences it? Finally, how does one actually measure it?
From what I understand, the reduction and oxidation of bonds ...
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2answers
348 views
Gel electrophoresis - What causes the DNA fragments to stop?
I'm currently studying VCE BioChemistry, and we're studying the separation of DNA strings of different lengths via Gel Electrophoresis.
(This involves having 'clumps' of DNA at one end of a gel ...
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121 views
What is Cβ (C-beta) deviation?
Molprobity and some other protein structure validation tools report a Cβ deviation statistic and offer plots for it (example below). Apparently if the Cβ is greater than 0.25 Å, some ...
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1answer
204 views
What software is used to generate the PDB molecule of the month images?
What software does the PDB use to generate these "cel-shaded" protein models with outlines around foreground atoms?
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1answer
108 views
What are the border definitions in the Ramachandran plot?
I've heard some people mention that this or that program isn't "up to date" with respect to the borders used in the Ramachandran plots to classify φ/ψ as being in the most ...
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120 views
Why does the sulfone ring in tazobactam open when the lactam is hydrolyzed?
One of the drugs I work with is a beta-lactam (4-membered ring with an amide bond) fused to a sulfone ring, tazobactam.
It's relatively stable in water; the lactam is not significantly hydrolyzed ...
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201 views
What are known examples of drugs that racemize/stereoconvert in vivo, and how are they converted?
It is known that although only the (S)-enantiomer of the infamous sedative thalidomide possesses teratogenic properties, it is not very useful to administer the pure (R)-enantiomer since it is ...
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2answers
222 views
Molecular explanation of the Hofmeister Series
The Hofmeister Series is a useful metric in understanding how to precipate proteins. However, wikipedia and many other source indicate that the order of the series is rather empirical. I'm curious ...
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1answer
156 views
Do terminal amides participate in $\pi$ stacking?
In a crystal structure I've determined, a triazole ring on my ligand appears to be stacking with a tyrosine (top in picture):
However, there is also an amide, courtesy a glutamine, near it ...
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1answer
716 views
Side reactions of NHS Chemistry
N-Hydroxysuccinimide (NHS) chemistry is commonly used in chemical biology to react with primary amines like lysine and the N-terminus of proteins. I was curious how labile NHS esters are to other ...
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103 views
What is a good method to measure the redox potential of a cellular system?
I know how to measure the concentration of free thiols which is reflective of the redox potential of cellular compartment such as the cytoplasm or a lysosome.
What other methods exist?
