Biochemistry and Molecular Biology

Many historian believe that most of the plagues started in steppes of Central Asia. It is a vast area of grassland that even today still supports one of the world's biggest plague reservoirs. It is an area where rodents live in great numbers and density. Why don't we just exploit it, as in right now?

If two viruses with totally different dsRNA invade a same host cell, will RNAi still work?

Does anyone know of a simple procedure for isolating DNA from E. coli? I have considered using a freeze-thaw method with a freezer to lyse the cells, but I don't know if that would be most efficient. I have also seen some methods that where phenol is simply used to do it. If I did use the freeze-thaw method, would I need a buffer in the solution? How much bacteria should I put in the water to be freezed? For the DNA isolation, I wanted to use a centrifuge with equal parts of the cell mixture and phenol, but I'm not sure how long I would need to do that for. Is that the correct mixture to put in the centrifuge? After centrifugation, how would I separate the phas…

I am using a UV spectrophotometer with DNA. If there is degradation of base pairs, would I expect to see a higher or lower absorbance value? There are more DNA strands after base pair loss, due to the strand being cut into pieces, but with fewer bases in total. So, the concentration will technically be higher? In that case, would the absorbance be higher also, or am I looking at this wrong and it only depends on the number of base pairs?

Hey people, This is a chemist proposing a simple playful thought experiment. Any ideas on what you might expect to happen if suddenly all the water molecules in your body (and the universe) were changed with respect to their bond length, which are enlongated by somewhat 5 %? So instead of the typical equilibrium bond length of 95.8 pm, it would be 100.6 pm. The bond angle remains the same. In the case that some vital organ is damaged by the sudden change in the density of water, you may comment on that. You may also comment on the case where this is not an issue and somehow balanced out. Would you believe this to be enough to kill us off? Are binding pocket…

Dear Sir or Madam, I do not really understand how to design a primer for a given DNA sequence. For example I have given this DNA sequence 841 aaaccagagc cggccagcca gtgaaacagc caccgtggag gggggacggc gaaaa***atg***aa 901 atccaaccaa gagcggagca acgaatgcct gcctcccaag aaacgtgaga tccccgccac ... 3241 catcgaaggc cgatctaacg tgggcaag***ta g***agaccttgc gggcagcgga ggcccggggc 3301 ctccttttac tgtctgtatc cagattactg tactgtaggc taagtaacac agtatttaca Now I want to design Primers for a PCR to amplify the region marked by the start and stop codon. How do I do that? What do I need to concern? Can you recommand any literature where th…

Hey guys, can somebody help me to identify what these colors on ideogram mean (picture included). There are Genome Data Viewer legends, but they do not tell anything about these colours (example: pink in upper ideogram or orange/greenin other one). Thank You. -DN

Hello, i recently read at book at school that said , that ultraviolet light destroys peptides. It didn't tell more about his topic, so i did some research on the internet, but i still don't understand one thing and my teacher wasn't sure about this: I read certain articles and sometimes the degradation rate of the peptides was more affected by UVA and sometimes by UVB. Why is that? is is because of the different amino acid profiles of the different peptides in regards to at which wavelength the absorb or don't absorb the ultra violet light? thanks for your help

Hello, I was reading a scientific article which reported that oral administration of a mutated form of apolipoprotein A1 (ApoA-I) to mice fed with a high cholesterol diet significantly lowers the rate of formation of atherosclerotic plaques. But I can't understand how this is possible. I mean, if mice are given the protein by mouth, it is digested into single amino acids, isn't it? So, how can it reduce plaque formation in the circulatory system if it is broken down by the digestive system? Thanks in advance!

Not certain if this is the correct gathering to place this in, however my pursuit in the Biology and Medicine discussions turned up nothing to my enjoying. My inquiry is this: Is it conceivable to land a better than average PRA position in a clinical research position with only a Bachelors? know somebody for whom this was the situation, however the activity was MUCH more managerial than logical, and in a perfect world I'd get the opportunity to accomplish something beyond noting telephones and organizing staff plans. On a similar token, I haven't yet had much enthusiasm for doing my very own investigations (ie. I don't generally mind to complete an ace's theor…

I am trying to get my protein into a deuterated buffer for NMR. I tried using the Millipore centrifugal filtration units and lost most of my sample to it. I am thinking the protein is sticking to the membrane. I am looking for a substitute buffer exchange method. Dialysis isn't an option because of the cost and quantity of solvents required. Any suggestions would be helpful. Thanks. CUP

ATP-ADP translocase mediates the exchange of ATP and ADP and this favored by the proton gradient across the inner mitochondrial membrane. But is this transport process an active process? I mean, are ATP and ADP transported against their concentration gradient or not? I don't understand if the function of the proton gradient is just to further favor an already-favorable process (passive transport) or to make possible an unfavorable process (active transport). Thanks in advance!

I was just wondering how is it possible that boiling water destroys organism. Human tissue for example. What happens to molecular structures? Do they move so fast so they can burn our skin? But how? Mars, Jupiter and other planets - they all have a temperature we simply can not survive. But what if we do something about it? Like editing our own body on molecular basis to allow us to survive these extreme temperatures. But as first we have to understand how does it work. Could you please tell me?

I was wondering about how do you change patterning during embryo development to create zebrafish with lungs. I am thinking about swim bladder as a base candidate organ (as in lungfish) and basically, you have to have mesoderm and endoderm interactions. It is false and not true that we all have gilts during fetal development. So the next step in evolution has to be lungs after them. I am pretty sure, based on evolution which is lazy, that you would need only a few point mutations in genes promoting the development of lungs in the chick. Wnt, Bmp pathways, TgfB for branching. But how do you see that, what would we have to do? Let say that we have all the options available.

Am pretty sure that you have read all the fuzz about fathers passing on mitochondrial DNA. I have read a paper saying that Mitochondrial DNA can be translocated to the nucleus, several diseases can be caused by this phenomenon like pallistor hall syndrome is it possible that the two events are closely associated

Dear friends, please, help me to explain an odd situation regarding an AFLP analisis of perennial forestry crop and reading of fragments in AppliedBiosystems capillary ABI 3130. The situation is following: - several samples of DNA from the clonal progenies of the same tree, all the trees are young, grown at the same location - AFLP profiles, as expecting, should be the same: no mutations in short time in the young trees after vegetative propagation - BUT, they are not the same: there are significant differences detected by AFLP. I guess, there are some catch in the reading of aflp profiles: rfu values. It is common to read just fragments that are strong…

I did an experiment on the effects of changes in temperature on the reaction of catalase in beef liver. I put a small piece of beef liver in hydrogen peroxide (with different temperature) for a minute and used a gas syringe to measure the amount of oxygen produced. My result is that as the temperature increased, the amount of gas produced kept increasing as well. However, I know that there is supposedly an optimum level, and the reaction should decrease after that level. I am not sure what I did wrong and what temperature should have been the optimum level. (I would do my experiment again, but our teacher said we cannot do any more experiments.) I would really a…

I want to ask what is active transport ?

Please, if anyone knows are there any inhibitors of phosphoinositide specific phospholipase C, synthetic or of natural origin. Thank you.

Why are ketone bodies only produced in the liver? I guess because some enzymes involved in their synthesis are only present in this organ, but I wasn't able to find this information in my textbook. Can someone help me? Thanks in advance!

Hello, is muscle glycogen phosphorylase sensitive to glucose? I mean, is glucose an allosteric effector for the muscle isoform of glycogen phosphorylase? My answer would be no, but going through Voet's Biochemistry book I found a diagram in which glucose is depicted as a negative allosteric effector for glycogen phosphorylase in general, without specifying muscle isoform / liver isoform. Thanks in advance!

I understand that the proteins must be separated before visualized by the antibody which requires electrophoresis, but I wonder why a native gel electrophoresis would not be preferred as it seems the antibody would recognize the native protein, not the denatured protein as caused by SDS. Can someone enlighten me please? Thanks!

whats the role of mineral elements in the metabolism of algae?

I'm running an assay that calls for use of trypsin to cleave a fluorescent peptide reporter, and the protocol specifies that trypsin (lipholized) should be aliquoted out at 300X working concentration and frozen at -80 for storage. The protocol does not include a resuspension buffer. My question is, is it ok to just use DI water to reconstitute the solid trypsin that I have and then freeze at -80? Most of the literature says that trypsin life can be lengthened by first dropping the solution pH with either 1mM HCl or 50mM acetic acid to reversibly inactivate the trypsin so it doesn't autolyse itself during storage at 4 or -20. I can't find anything about -80 storage h…

Hello, i was reading an article about temporal control of cortical mammalian neurogenesis and the authors say that RGCs (radial Glial Cells) act as neural stem cells and differentiate into IPC (Intermediate Progenitor Cell). Then, these IPCs can differentiate into neurons. (RGC => IPC => Neurons) But later in the paper, they talk about NPC (neural progenitor cell) and i'm a bit confused by this term. So here is my question : - is NPC a group of different kind of progenitors in which are IPCs ? And if yes, why do they talk about NPC and not IPC ? Thank you Paper : Temporal Control of Mammalian Cortical Neurogenesis by m6A Methylation (Cell, 2…