Biochemistry and Molecular Biology

"Particles can aggregate and settle out of solution through four basic mechanisms: double layer compression, sweep flocculation, adsorption and charge neutralization, and adsorption and interparticle bridging (34, 35)." I can't understand these mechanisms, would someone explain them, please?

Hello there, I wonder if anyone might be able to explain to me what a protease-resistant core of a protein is, specifically in regard to its amino acid sequence (does it lack protease specific amino acids, e.g. K and R in the case of trypsin?) and means of formation? Many thanks

Appologies if this is not the correct place to make this post. I was wondering whether anyone has an installation CD for Polarstar Galaxy Plate reader? We have misplaced ours and need to reinstall on a new PC. The Company no longer supports the instrument and told us that they are unable to supply a duplicate CD. We have software for our other Polarstar Optima, but unfortunately it doesn't work with the Galaxy instrument. If anyone has a copy of the CD and wouldn't mind letting me have a copy, I would be really grateful. Many thanks Mike Orford

I didn't bother to look up the specific cannabinoids that reduce diskynseia nor the mechanism, but we all know that it works. To get around state laws regarding cannabis oil..why not just separate out the select cannabinoids that contribute to diskynseia reduction? I could probably do it in a university lab using a column in a day.

I'm trying to understand how this isoflavon thing can lower our blood glucose levels, like it does on rats... From what I've read, it increases insulin secretion, or due to it's estrogenic properties, it affects the beta cells... but how does it make these happen??? can someone take a look at the articles and explain to me in simpler words since I've had a really tough time understanding these? thank you ) here are the articles i've read though, some of them: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3678366/ https://www.ncbi.nlm.nih.gov/pubmed/15650341 https://www.ncbi.nlm.nih.gov/pubmed/19083447 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2849033/ …

Hey guys, I am doing an animation about the synthesis of proteins on ER. Remember the moment when Signal Sequence is cut off by Signal peptidase and leaves the translocon? So, I animated it going into the lipophilic part of the membrane (oriented horizontally), but then noticed that all images show it oriented vertically (see attachment). Isn't it supposed to be lipophilic? What would be the most correct way to orient it inside the lipid bilayer? Thank you for your time!

Hello, I have been wondering if this coomassie blue stainer is good investment, has anybody tried it? It's because im tired of my current... Product: http://www.coumassieblue.com/ Thanks HeartDriveR

Hey, if I start a titration of Histidine at the pKa of the N-terminus (pH of 9.1) with HCl, where would the first equivalence point be? I was thinking that the 1st equivalence point would be between 9.1 and 6.0 (pI) however mols of acid would not equal mols of base until the pka of 6.0 is reached. On the titration curve I must label where this equivalence point is but I have never started a titration at a pka before, can someone please help? thank you!

Why use ice bath for Sakaguchi test (guanidine group quantification)?

What causes alleles to become dominant or recessive? How does RNA 'know' which allele is dominant and which is recessive? How does itbind with the correct one? If a recessive allele causes the fittest phenotype then the recessive allele will become dominant(after a long time)...this causes the huge variation. How is this possible? Alleles which become dominant have the most interactions with RNA. Can RNA alter the dominance/recessiveness?

Hello all, I have two questions. How can expression of a foreign gene be made tissue specific? And a second question: how can a promoter be made tissue specific? Thanks in advance!

Hello, I am new to this forum, so bare with me. I am working on a project that requires me to ferment sugar water with Lactobacillus Acidophilus. I made a 50% concentration of sugar mixture and it will not ferment. Apparently 50% sugar is too much. Does anyone know what concentration of sugar will allow the bacteria to ferment the sugar? If someone could answer this for me I would be absolutely delighted!

Hello all, I am 24 y/o and work for American Medical Response, Monterey CA, on the ambulance. I am looking for a Biochemist who would be interested in discussing an idea I have for a new medical invention. Thank you for reading and please let me know if your interested.

in dna hybridization different annealing reactions can take place one of them is background interaction of the probe is somebody know what is this and how its happen thank you.

I'm trying to find the longest contiguous sequence ever established using the maxam-gilbert (chemical degradation) method. I've found no references to this in literature. The only other way I can think of to do it would be to filter something like the ncbi nucleotide database to show only sequences that used this method and then sort by length, but if that's possible I can't figure out how to do it. Please help.

A pure, 70 µM sucrose solution is partially hydrolyzed and after which the amount of reducing sugar was measured to be 0.12 mM glucose equivalent, greater than the amount of sucrose to start with. How is this possible and what percentage of the initial sucrose was hydrolyzed? I'm struggling with this question so would love some help!

In the process of photosynthesis, electrons are 'energized' and injected into the electron transfer chain to eventually pump H+ into the lumen. What does 'energized' electron actually mean. Is the electron supposedly spinning faster, vibrating faster, or what? Because it cannot have its velocity changed. What exactly is an energized electron? And how is it different from a non-energized electron? Thanks

I know some compounds are toxic when they are metabolized (i.e. amygdalin in apple seeds is converted to cynanide via digestion). But what would cause a protein to be toxic? They shouldn't be toxic because of what they're metabolized into, b/c they're mainly linked amino acids. Is their toxicity derived from their specific conformation/ properties..like ricin? I guess what i'm trying to ask is, are proteins nontoxic when they're denatured (i.e. no conformation) or are they still toxic even when denatured b/c of their metabolic product. ~EE

I am a 2nd year Biochemistry student and have been given this supposedly 'basic' question, but I'm really struggling with it. "1.068 g of an amino acid (pKa1 = 2.4, pKa2 = 9.7) was dissolved in 100 ml of 0.1 M NaOH to produce a solution with a final pH of 10.4. Calculate the molecular weight of the amino acid. What is this amino acid?" Does anyone have any ideas on how to tackle this? Any help would really be appreciated.

As far as I am concerned, photosynthesis does produce h2o But after studying both light and dark reaction, I didn't find out any water molecule produced Can you help me point out which reaction does that

The recipes I have seen for the bicinchoninic acid call for 0.16% disodium tartrate dihydrate (I don't yet have the original 1985 reference). I have sodium potassium tartrate. Using this would produce a concentration of potassium ions of 7 mM. So far I have not seen anything to suggest that potassium interferes with this particular assay. However, the Lowry assay is also based on copper ions, and 30 mM potassium phosphate is listed as the highest acceptable concentration (Bollag et al., Protein Methods, 2nd ed. 1996). On the other hand one recipe I consulted (Ninfa et al.) for the Lowry assay calls for use of sodium potassium tartrate. ThermoFisher's website suggest…

In glycolysis, I learned that the reaction Fructose6P to Fructose1,6BP is irreversible, yet in the non oxidative phase PPP, somehow F1,6P is converted to F6P so that Glyceraldehyde 3P become Glucose6P. How is this possible? If the reaction is reversible ,will the regulation of the enzyme be pointless? I will add an image for this. As you can see, G3p is transformed to F6P which is only possible via F16Bp

Hello all, I was curious if anybody had experience with (or could theorize about) the effect of a His-tag on a protein run in a gradient Native PAGE gel, versus the un-tagged form. Some more details about the type of gel are that it is a clear Native gel, so no Coomassie has been added. Another factor is that this is a gradient gel, so proteins will separate according to size as each reaches its pore limit and establishes a running pattern. Any information on this is much appreciated!

Hi! I would like to perform experiment connected with activation of all three pathways of complement system in fish (classical, alternative and lectin) on microtiter plates. Already I know how to perform an activation of alternative pathway (set up protocol and so on), no idea how to do it to get results for classical and lectin? Any help? Suggestions? Protocols? Articles?

In tRNA, rRNA, and ribozymes there are stretches of RNA that are bonded to compliments by hydrogen bonds and form helixes. There are also loops. Do the bases that form the loops have their hydrogen bonding regions facing outwards? I have attached a file to illustrate my question. Does the RNA naturally twist so that the bonding region is pointing outward?