Biochemistry and Molecular Biology

That is all.

I understand the factual differences between both types of muscle fibre but how would they differ in a cross section? If you can refer to any sties/books on muscle fibre composition and differences that would be appreciated.

Hi All, I'd like to know if there are any known enzymes that cleave the sidechains (not the backbones) of lysine or arginine. Smaller enzymes would be better. If unknown for lysine or arginine, please let me know of any enzymes that will cleave the sidechains of any protein. Thanks, John

Hey! So, I'm after reading a tirade of experimental papers and journal reviews for a college assignment and all of them seem to glorify their subject molecule as either "crucial", "extremely important" or "invaluable". For a change, instead of hearing about vital, couldnt-do-without proteins and PTM's... I'd like to hear about a completely dispensable and redundant protein. What do you think is the least important human biomolecule? I vote for one of the many olfactory receptors we have.

Hello I would appreciate some assistance with the following review questions as my exam is coming up in a few weeks I'm just revising my content, however, there seems to be a limited range of practice questions and when it comes to these I seem to struggle, so would appreciate some explanations/walkthroughs as to how to do them so I may learn. ESTIMATING GENE NUMBERS Approximately 1% of the human genome consists of protein-coding sequences (exons). A diploid somatic human cell contains 5 picograms/pg of DNA and rapidly growing E.coli cells contain on average four genomes giving a total of 0.017pg of DNA. Assuming that the sequences within the E.coli DNA codes for p…

I essentially need to dissolve a substance with a high percentage of keratin. The tricky, counter intuitive, conundrum is dissolving something without drastically altering its molecular structure. This is because the substance/liquid will then be "re-polymerized" back into a solid filament. FTIR scan practically identical to hair. We are using FTIR to basically take a before dissolving and after dissolving shot, if they look similar we can move on to the next step. Thank you in advance for any responses or contributions, I appreciate it. -S http://www.google.com/patents/US2542984 This could work...maybe

Hi, I have a simple semantics question. I have been reading some literature that seems to consider RNA Primers as part of Okazaki fragments, but this should not be so because Okazaki Fragments by definition are just the DNA portions synthesized on the lagging strand. Any opinions/clarifications on this?

Though most human cells are constantly being replaced, we keep most of our brain cells (and some others) throughout life. While a specific brain cell continues to exist, are the individual atoms in that cell gradually being replaced? Are individual atoms replaced in cellular DNA? Quantum physics tells us that atoms are popping into and out of existence all the time.

I have a Block Co-Polymer that is a type of fiber with an FTIR spectrum very similar to hair. I need to some how break down a fiber, and synthesize it. If I could, which I can't, this could mean simply melting it and pouring the molten fiber into a mold. What are some methods that you can suggest I try? I feel that dialysis could be a option (spin in tubing, against acid or acetate based solution in hopes that something permeates through). I need to choose this route as opposed to artificial synthesizing because the material I'm looking at is incredibly complex to the point where mixing and chaining peptides would be very expensive (no one has successfully taken s…

Hi guys, is there anyone here that can tell my how to introduce a tetralinyl group into my sample. I have very little chemistry understanding so I have no idea which chemical solution to make up for this. Thanks for any and all help. Kiko

Hello, in this picture i have attached below, I am having a hard time determining if my unknown is either coccus or bacillus shaped. I used a gram stain by thr way which tested negative.

Hi I'm sorry if I make mistakes, but I'm not 100 % familiar with the English language . In most of the books I can found only information that chlorophyll is used to absorb the quantum of electromagnetic radiation and transfer electrons to the reaction center. Nowhere I can't find any information on that, I hope some of you may know: -molecule of chlorophyll- for me is a cation, cuz of Mg2+ in the center- whence chlorophyll takes electrons? -when a photon hits the magnesium, whence Mg gets the electron and on what principle the electron moves from one chlorophyll molecule to another? -when the photone strikes an electron and take it from chlorophyllcan I say that c…

Hello everyone, New on here but just need some advice. I've been asked to create a list of possible enzymes for immobilisation as part of my Final Year Project at University. However I've been asked to include enzymes that have not yet been immobilised. I'm finding it very difficult to discover whether certain enzymes have or haven't been immobilised before. Just wondering if there are any websites or lists you could refer me to that could possibly help me out. Thanks!

Are there test kits or other fast standard assays for monitoring ”macrophage fitness” in vitro? I would like to do infection assays (on plates). Beside CFU counts of the bacteria I would like to have an idea of the fitness of the macrophages. We usually check the macrophages by microscopy , however another more quantitive approach would be preferable. Thanks

Was wondering if anyone has any experience with BEMAD. I'm trying to map sites of O-GlcNAc modifications on my protein of interest via MS/MS but the fragmentation energy is too high and so knocks the O-GlcNAc off the peptide before it's read so you can tell it was there but not where exactly it was. Using Beta elimination followed by Michaels Addition of DTT (BEMAD) you can replace the O-GlcNAc with a DTT moiety which should be able to survive fragmentation. Then by mapping DTT modified sites, you can tell where the O-GlcNAc was. My Question is does anyone have experience using BEMAD and if so could you post a protocol that worked for you to use as a jumping off p…

I've been tasked to come up with alternatives to generating an isogenic mutant bacteria for studying gene function and phenotype. I've come up with the conditional mutants. I'm hoping to find at least one more alternative. Can anyone direct me to a protocol or a paper? Thanks, bwschn01

people, Think this is true, or just suspect at this time? I mean, geez- fructose as in sugar found in an apple?? Worse at producing insulin than cane sugar??

In the liver, the glucose stored in glycogen molecules is liberated via phosphorolysis in the form of glucose-1-phosphate in a reaction catalized by the enzyme glycogen phosphorylase. Glucose-1-phosphate is then converted to G6P by action of an enzyme called Phosphoglucomutase. And, finally, G6P is converted to free glucose by the enzime glucose-6-phosphatase. This free glucose is now ready to leave the liver and enter the bloodstream. My doubt is: why is not the glucose stored in glycogen directly converted to free glucose by hydrolysis? Instead of following the longer path: Glycogen -> G1P -> G6P -> Free glucose. Thanks in advance, and sorry if ther…

when I used blue filter, although I did not stain my cells, I see my cells like in attached photograph I am lost.... Is there any explanation of this???

Hi, I must write report about "Proteins, that contain Iron, functions and classification". Currently i have problems searching for classifications.

What would cause the loss of relative activity in an enzyme over time? And how would this factor in when you use elution and wash buffers and dialyze your sample? Could this be reduced by being more careful with how much buffer you add?

I always thought that atoms and molecules tend to hold no charge unless some force is involved. I'm learning about the electron transport chain in particular, and about redox reactions in general, and it seems that there are continual changes in positive and negative charges. Is there something powering all of these changes in charge, or am I mis-remembering the thing about atoms and molecules wanting to remain neutral? I understand that if the molecules are polar, the water molecules in the cytosol could pull them apart, resulting in charges, but what would cause them to continually gain and lose electrons, as in the case of NAD+ being transformed to NADP and then back …

How do enzymes actually increase the rate of a chemical reaction ? Take ATP Synthase for example , how does it work ? does the rotary motion squish the the inorganic phosphate to adp and make it chemically bond to form atp ? Likely not , Can someone explain to me what exactly happens ? What about the enzyme catalase ? I believe It does not have moving parts . What exactly happens in the active site of catalase ? Sorry for stuffing in these many questions .

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…