Biochemistry and Molecular Biology

hi i'm not a biochemist or molecular biologist, but i'm interested in something for a research project ... could anyone give me any examples of areas of medical research that require analysis of the results by a human, rather than by a computer? cheers alex

How simple or complex is it ? What amount of deeeep knowledge is needed to do such ? Or is just to read a instructional and do it as explained there ? Just an example : vinpocetine or ethyl apovincaminate; reportedly extracted from a plant vinca minor, which shows bearing a dozen chemicals; is each one an entire world of knowledge in how to extract, what proven applications has... But... comes from bark, root, fruit, flower... Where is it found in written ? Is there a 'CRC' type of fat book for such knowledge ? Or are these industrial/pharmaceutical top secrets ? How to find how is it done; if it is extremely difficult, critical, or a piece of cake; it t…

A non-competitive inhibitor tends to bind at an allosteric site and prevents enzyme function. However, can the substrate still bind the enzyme even though there will be no activity as long as non-competitive inhibitor is bound? Or does the active site change conformation as well, thus preventing the substrate from binding?

Hi all. I use 0.5 M NaOH for cleaning anion and cation exchange resins and need a quick/efficient way of removing the NaOH before storage in 20% ethanol. H2O does not work quickly enough - can take more than 10 column volumes. I think I need a buffer at high concentration (1M) that can displace the OH- ions quickly, then I would follow with H2O (so salts won't precipitate when ethanol is used later for storage). I'm hoping to use maybe 1 column volume of high concentration buffer and 2-3 column volumes of H2O. Which buffer(s) would work well? I would prefer to use the same buffer for all cation and anion resins if possible for convenience. Any advice?

Hi everyone, I have some 20-aa peptides which I've had synthesized. The problem is I need to determine their concentration after they have been dissolved in water. (They don't dissolve fully so it's not possible to simply consider the weight of the lyophilized peptides beforehand). Each peptide has a fluorescein molecule attached at the N-terminus. So one way I've been doing it is to measure the absorption of the peptide solution at 490 nm (the absorption of fluorescein). I can then compare this absorption with absorption values of known amounts of free fluorescein at the same wavelength to calculate a molar concentration of the peptides. Do people agree with this…

Hi all, I have been searching everywhere for a straight answer but haven't found one anywhere, so thanks in advance for any help. Is is possible for an agonist to have more than one efficacy at the same GPCR, one for the action of the alpha subunit and another for the beta-gamma complex? My logic would be that the interactions with downstream effector proteins could have a higher/lower activity for each subunit. Hence, what might be only a partial agonist through the alpha subunit may in fact be a full agonist for the beta-gamma pathway. Again any help or ideas are much appreciated. Iain

I'm starting an experiment soon involving eliminating contaminations such as green bread mold and various bacteria. I have access to a college lab and an expert on bacteriophage, but I plan to start with the Trichoderma and haven't been able to find much on it as far as viruses go. Does anyone know if a virsus has been identified that attacks this family and if it can be purchased or the most likely place I can find it, such as soil or water? I figure I'll start out a lot of petri dishes of agar with cultured Trichoderma and start exposing it to various things, like soil samples if a virus can't be purchased. Any help or advice would be appreciated.

Can anyone please confirm that the structure of oxytocin on the wikipedia page is accurate? http://upload.wikimedia.org/wikipedia/commons/5/55/Oxytocin_with_labels.png there are other versions on the web. thanks so much, Joanna

Hi everyone! I was doing a test with biuret solution (which tests for proteins by turning various shades of purple) and put some in a test tube with dextrose. At first, a white clump formed at the bottom. I put a stopper on the test tube, shook it, and after a little bit it turned red and then brown. I can't find any information about biuret solution turning brown. Another group had the same result. In the presence of gelatin, it turned light purple. I am not 100% confident this is biuret solution, but what else could turn gelatin purple? The solution was blue in colour. Why did it turn red? EDIT: When mixed with vegetable oil, a seemingly sol…

Dr. M.L.P. Collins at the University of Wisconsin-Milwaukee has developed a new method for making large quantities of active, viable proteins using Rhodospirillum rubrum as a host. R. Rubrum is a bacterium that has traditionally been studied for its simple photosynthetic system, has demonstrated recent success in expressing high-yield protein. To provide a brief overview, R. rubrum possesses the unique characteristic of forming an intracytoplasmic membrane (ICM) in response to membrane protein synthesis. The ICM is non-essential for growth and can incorporate foreign and over-expressed membrane proteins without disrupting normal cellular function. This characteristic…

If a -RNA virus were to infect eukaryotic cells, that virus would need to carry its own polymerase to first become a +RNA virus and then use the host cells machinery to undergo translation, correct? Under what circumstances would that virus choose to use reverse transcriptase and become DNA and what would the benefit of that be to the virus? Is it to replicate its own DNA by going Lysogenic and then excising itself?

Hello house! Please i need to juxtapose the amount of ATP that will be produced or gained for one molecule of Apartame a diabetic patient takes instead of one molecule of sugar. It is part of my Mtech course work. Thanks

Hello. i have some question regarding use of bradford method. why is linerization of the bradford method more uncertain near 0 mg/mL concentration of protein and above 0,9 mg/mL where it bends off. In an experiment, the regressive line usually never goes by (0,0) which i assume has something to do with the uncertanty. Using the UV - method give a more "perfect" regressive line with high precision, but if measuring contaminated protein, often gives an overestimation of the concentration, where the bradford method gives a more correct assumtion of the concentration but with lesser precision. Why is the precision lesser with bradford method?

can any one help me on bacterial rnase activity assay? which is the bst method for it?

If a person is fasting, what biochemical processes occur to generate energy to get the person through this period. Since the body is low on glucose, gluconeogenesis would occur to synthesize more glucose so that it can enter glycolysis and be broken down. The body would also undergo fatty acid synthesis on the mitochondria which would enter the Krebs cycle to generate energy. Proteins would be broken down into amino acids and those amino acids would enter Krebs as well? If all of this happens, then why do Ketone bodies form and what is their purpose?

If one wants to separate DNA better using a gel would they use a higher percentage of gel or lower percentage? I was thinking a higher percentage because that would make the gel more viscous and dense and thus promote better separation. Was this improper thinking?

For example, why do we need both leucine and isoleucine? Does anyone know of a good book or review article that discusses (or even speculates) on this question?

If a cell were to be deprived of oxygen, what effect would this have on b-oxidation? I know that the cell would go the route of lactic acid fermentation but would/ could b-ox still occur in the mitochondria and if so, does that mean that Krebs would still occur as would the electron transport chain?

Hello you guys, I was just reading about lipids synthesis, triacylglycerol and phospholipids to be more exact, and there's a thing that confuses me a bit. We all now that triacylglycerol is stored in the adipose tissue and broken down, after which free fatty acids can enter the blood. Now to quote Stryer 7th ed. it is said that "The liver is the primary stie of triacylglycerol synthesis (okay!). (But but..) From the liver, the triacylglycerol are transported to the muscle for energy conversion (beta-oxidation that would be?) or to the adipose cells for storage" My question is now, why the heck would the liver produce triacylglycerol for the muscle, if the the m…

Hello! We've all heard of essential amino acids, which can not be synthesised in our own body. My question is, why can't we do that and also how come are animals capable of synthesising them? I appreciate all of your answers.

Let me preface this by saying I am a senior in high school taking AP Biology. Currently, we are studying glycolysis, TCA cycle, and oxidative phosphorylation. Were taught many years ago that the oxidation of glucose to harvest energy can be generalized by C6H12O6 + 6O2 -> 6CO2 + 6H2O I am trying to account for where all of these molecules are either consumed or made. One glucose is used in glycolysis, which makes 2 NADH + 2 protons. Pyruvate oxidation creates an additional 2 NADH + 2 protons and 2 CO2 (per glucose). Two cycles of the TCA cycle produce 6 NADH + 6 protons, 2 FADH2, and 4 CO2. So far, the glucose and the CO2 have been entirely accounted…

Hello everyone, I am curious if you have had this experience before. Currently I am visiting a lab and have been getting really strange results while using their columns for protein purification. The short version is that I've been getting large absorbance peaks (500-2000mAU) on my chromatograph without any protein showing up on my SDS PAGE results. I've had this occur with two different proteins and different different buffers. Any thoughts? Thanks!

I work on FLS2 and I am trying to find the sequence in Landsberg erecta to compare it with the Col-0 one.

I've been looking into the kinetics of polyphenoloxidase catalysis of the oxidation of catechol. I've run the reaction at seven different catechol concentrations () both uninhibited and in the presence of trypsin (measuring using spectrophotometry). The data came out nicely and I've been able to calculate Vmax and Km values that I'm pretty comfortable are accurate. However, I am hitting a wall on kcat. Since I obtained my PPO directly from potatoes, I don't have a value for [Etotal]. My question is, is there any way to work around this? Since kcat=k2 in this case, I've tried setting up simultaneous equations using kcat = Vmax/[Etotal] and k2 = v0/[ES], however, [ES] …

At a pH below their pI, proteins carry a net positive charge; above their pI they carry a net negative charge. ( information from Wikipedia) why is this happen?? Can anyone explains the theory?? If talk about glutamine acid??