Biochemistry and Molecular Biology

i am not a bio(major) but i have a doubt:: when we climb a flight of stairs obviously we are putting ourselves in a higher gravitational potential and hence higher energy state. so, we need to expend some sort of biochemical energy and hence feel a bit tired. but, when we get down even we feel tired(not that much) and according to me we even expend energy in this case.now, again considering the gravitational potential energy, we now need to gain gravitational potential energy(consider that we climb up and down the stairs with the same velocity so no change in kinetic energy)1. isn't this a violation of the energy conservation?? if not, then let me know how our cells/muscl…

I'm not sure if this is the place to ask this but I hope it is. Our professor gave us this homework to solve and I was wondering if someone could just tell me if the answer is correct or not because one of my friends told me there were "mathematical and scientific" issues with the way I solved the equation or the numbers I used The homework and Excel file which includes the graph is in this link. I apologize for the messiness, lack of scientific language and probably not being clear in some parts but this is a very rough draft, I just need to know if what i solved is correct since my friend's remark made me doubt everything I did. Thank you very much in a…

I'm working on a graduate level research project, during my undergrad, concerning yeast genetics in budding yeast, and neither myself nor my faculty advisor are able to answer a specific question when it comes to preparing yeast growth media. The question is: will caramelization of dextrose in solid media have a large or significant impact on the growth of budding yeast on the plates?

I was studying single nucleotide polymorphism (SNP) and got really confused with the example of 4G/5G insertion/deletion polymorphism at -675 promoter region in Plasminogen activator inhibitor-1 gene. Does it mean 1G is present or absent in -675 position? What does it meant by 4G/4G, 4G/5G and 5G/5G genotypes? In case of deletion, if a G is missing in -675 position what's in there in place of that? Also, how is it possible to have 4G run in one allele and 5G in another allele for the same position? I'd really appreciate if anyone could shed some light and clear the concept here..what am i missing? Thank you!

CJD is an example of a disease caused by the misfolding of the protein PrP© I have been researching this disease somewhat and have discovered there are several variants including sporadic CJD and variant CJD. It appears that the different variants of the disease have different risk factors and different physiological effects. Given that they are all caused by the misfolding of the same protein - PrP© - I was hoping someone could explain to me why the physiological effects of each variant differ in some respects [including:median age of death, duration of illness and some clinical signs/symptoms] thanks

I'm currently working on a fourth year molecular biology project and I'm having some trouble importing files into pymol. What I want to do is create a custom ligand and import it into pymol with a pdb protein file. So far, I have tried using marvin sketch to create the molecule and trying to import the file via different file types (pdb,cube,mol ect...). Pymol either crashes or it makes the original protein disappear. Does anyone have any suggestions? Should I maybe use a new program altogether? David

I usually got an melting curve with multipeak. Can anyone tell me what is the exact cause for this

hey i have a serious doubt..leucine codes for UUC and its IUPAC name is 4 amino carboxyl pentonoic acid .how can one amino acid have two completely unrelated structures???

hello all I am new here and I hope you can help me out. I tried to do some Googling but I can't find the answer to this. The difference between iso-pentane and neo-pentane is in the arrangement of the atoms, they are both 5 carbon atom, with different structure. 1.But why is endorphin so different from neo-endorphin? The former has about 3x the number of carbon atoms as neo-endorphin? 2. What's the the practical function of endorphin and neo-endorphin? Which is the one that makes us happy? 3. And in terms of practical purpose, which is the more important one, alpha or beta endorphin? Thanks!

Is there something that can be added to palm trees to make them more tolerable to cold weather? If so, is there one that can be added to the tree without hurting it?

I'm trying to create an isogenic mutant in bacteria using a suicide vector that should experience two recomination events. The first inserts an antibiotic resistant marker and the second should remove the gene I'm trying to delete as well as the antibiotic resistance marker. I get the first recombination event, but when I induce the second, I'm failing to see a mutant genotype. I can't figure out why. Any ideas on what could be causing this?

Could anybody please tell me the chemical makeup of blood plasma? I already know about the different parts of blood, such as red blood cells, platelets, white blood cells, etc. I'm simply asking for the chemicals/substances that are the basics parts of blood plasma so that i could possibly synthesize it for an experiment I'm testing. (Real blood will not work for it)

I need to draw gene cluster diagrams proportionate to their actual size as shown in the attached picture, is there any way to do it easily, means a software which can help in such drawings with annotating

Hi guys In my studies I've had great difficulty understanding these two equations; I'm not mathematically minded, and however much I read over our notes or ask lecturers for help, its not clicking. If there is a kind and clever person on here who's willing to talk me through these equations with examples I'll be so grateful! Thanks a lot

I want to know in pET28a/BL21DE3 and also in pCold TF/BL21DE3 for how much time (hrs) after induction with IPTG culture should be kept and at which temperature so that soluble aggregates should not form? I kept at 18 degree for 18 hrs after induction in pET28a and at 15 degree for 24 hrs but there is formation of soluble aggregates in both as detected by Native PAGE . I read that if kept for long time protein forms aggregates or come in inclusion bodies.

My protein molecular weight is coming 40.7 kDa by gel-filtration and by gradient native page it is coming near 146 kDa and by SDS-PAGE it is coming near 40 kDa. I am not understanding this result as by gel- filtration and native PAGE molecular weight should come approximately same.

My question is that when eluting protein with elution buffer we set pH of elution buffer (sodium phosphate buffer) to be 7.5 but after adding 500mM imidazole pH of buffer increases to 9. I want to know is there need to adjust pH of the elution buffer after adding imidazole to 7.5. If yes, then how can we set the pH by using NaOH or HCl or by adjusting with sodium monobasic or dibasic buffer salts or make buffer of less pH like pH 6.0 and after adding imidazole the pH will reach 7.5 after doing the standardizations that how much pH buffer to make so that after addition of imidazole it reaches 7.5 pH.

Quick fire question, what does each do....5-HT/1....5-HT/2-a/b/c et cetera Theres triptans that block migraines that work on the 5-HT/1's but purpose built to not act on 2-a/b/c?'s is it that 1's work in different particular neurological pathways to the 2's or such?? My biochem and neurology are in infancy so analogies work well Regards. UPDATE: Do the selective 5-HT,2/b agonist's give a non-psychedelic feeling? And what does blood brain barrier mean?

Does anyone know if trypsin can cleave D-form peptides, i.e., c-terminal to a D-arginine or D-lysine?

Hi guys, I'm doing some in vitro fatty acids oxidation assay following the protocol by Sweeney 2005 (Diabetologia 48: 132–139). Basically I trap the radiolabelled CO2 with filter paper which was previously soaked in phenetylamine:methanol and then I count the activity of each piece fof filter paper. To get also the CO2 that is in solutution in the medium (bicarbonate) I acidify the medium with H2SO4 to pH1. It kills the cells of course, but at that point I no longer care My point is: one of my collegues insists that she puts the H2SO4 on the filter paper together wiht the phenetylamine and than she incubates the flask (sealed) with this paper on the lid. Is th…

Hi, I have isolated 9 soil bacteria and sent for sequencing. I had identified them using BLASTn. The results showed that 5 of them belong to genus Bacillus, 2 strains belong to genus Serratia , 1 strain is genus Pseudomonas and 1 strain belong to genus Escherichia. Now, I would like to construct phylogenetic tree. However, I not sure how to do it. So, can I just construct a phylogenetic tree that only consists 9 strains of my study bacteria samples? Or do I need to construct a phylogenetic tree that consists of my study isolated bacteria together with some related bacteria species?? Please help me to remove all my doubt... Thanks.

I have a question regarding the CitP450. I would very much appreciate if someone could help me! If I administer two drugs, both metabolized by Cit P450 but one of them by one type of enzymes (citP450 2E1) and the other by other type of enzymes (CYP2B1 and CYP2C11) is there a possibility of interaction between the two drugs anyway? Thanks in advance Aura

I posted on these forums a few years ago links to some admittedly dubious articles and papers relating to topics regarding "wave genetics" and photonic radiation using DNA somehow between cells to coordinate behaviour and things of the sort. A lot of the work was done by just a few researchers who continuosly seemed to cite a few works of each other. At least this was the impression I gained after a discussion with one of my own professors about this work(he was pretty skeptical of photonics having any major role in molecular biology). I recently came across an article, that was linked across from somewhere Gariaev's work was discussed, from a researcher called Paolo …

Hello, I just recently graduated with a BS in Biochemistry and am having difficulties finding a job. I was wondering if anyone had any suggestions as to good companies to apply to and for future schooling. What are some things that you did after graduating with a biochem or similar degree? If anyone has any advice that would be great. Thank-you!

Heya, Stumbled upon an problem. We are trying to create nutrient broth with a range of concentrations of lead acetate in order to grow lead-tolerant bacteria. The problem is, when we add the lead acetate solution to the nutrient broth it immediately precipitates, it then reacts and changes from a white precipitate to a grey/black precipitate when we autoclave it. Anyone got a solution? We know its been done before, but we don't know how and seem to be missing something... Thanks