Biochemistry and Molecular Biology

Hey guys, I am curious about the step of glucose-6-phosphate (herein g6p) to fructose-6-phospahate (herein f6p). I know that from glucose to g6p, it requires a molecule of ATP, along with hexokinase. And I also know that phosphoglucoisomerase is the enzyme from g6p to f6p, but does this require an input of energy? And if it doesn't, can I assume that all the other steps through the glycolytic pathway that do not explicitly state the use of an energy intermediate is going to not require energy? Michael

I'll be doing some molecular cloning this year. Any advice on protocols and data analysis?

It is known that some bacteria are dangerous ONLY when they're in the wrong place, f.i. E. Coli. Does anyone know some more examples?

I know that breaking the phosphate group off is exothemic, and something is going on with entropy and free energy for the hydrolysis of ATP to be used for work in a cell. Take active transport, needs a conformation change in a protein to work - how does the cell use ATP to bring around this structure change?

- Can the carbohydrate content in foods be altered or destroyed by some type of process ? - What is proteinine ? I have the feeling of learning years ago, that is overcooked/overheated protein, that has changed its characteristics. Can you confirm ? Is there another name for such ?

On a discussion board about DNA sequencing I found this comment: "Instead of evaporating all of this, we bind it all to AMPure beads (2x cut), wash the beads once in 70% ethanol, dry them, and resuspend them in 10.5ul of hyb buffer. It takes all of 5 minutes, and no cross-contamination prone speedvac step!" I also found this comment elsewhere: "Particular care should be taken to avoid contamination of commonly used rotors. " From the context of the article, the author may have been referring to rotors used in organic precipitation of DNA or in post-precipitation drying of the pellet in a speed vac, but I am not sure. I also found ThermoScientific's literature ab…

FISH probes and Taqman probes are both called probes, but what's the differences between the two ?

Hi guys! The following question was asked as part of a finals exam in immunology. We have two human populations inhabiting two different geographical areas. Which genes would we expect to find to be more 'conserved' between the two populations. The ones that code for the TCR chains or the genes that code for the MHCs and why? Any help would be highly appreciated.

Hey everyone ! I would like to resolve a protein with a MW of 3 kDA by using a Tricine SDS page (16%), I've already got the standard (1,7 - 40 kDA) but every publications i found tell me that this kind of low range standard are stained with a Coomassie blue G-250. Is there any possibility to use a silver staining and still see the lowest range band ( 1,7 kDA ) or do i have to use a Coomassie to stain it ? Cheers !

As the name suggests, I am hoping for members to share topics that are the focus and discussion among scientists right now in cell biology. I am interested in synthetic biology, which I believe falls in this category and would like to learn about others. Specifics and examples are not required but certainly welcomed.

Hi All, Just a quick question regarding affinity maturation in response to an antigen. If the B cells are undergoing hyper mutation to produced the appropriate antibody for the antigen of the invader, do they not produce a huge number of wasted antibodies that will remain in the body ? As I understand it, (I may be wrong) they have to experiment with mutated antibodies to fit with the antigen, with only a tiny number of antibodies fit for purpose. I can't see how the body deals with all the wasted antibodies produced in the process ?

Hi everyone, I am currently doing a masters in Architecture and have to research the topic of vinca alkaloids in a lot of depth - just to let you know I am not from a scientific background so apologies if I get anything wrong! I have done a lot of research in to the method of action of vinblastine and vincristine (I am studying the Madagascan periwinkle in an attempt to produce a design based on bio-mimicry) as microtubule inhibitors, but my tutors would like for me to know exactly HOW the vinca alkaloids disrupt the polymerisation of the tubulin in order to kill the microtubules and prevent further mitosis of the cancerous cells. Here is what I THINK is hap…

In the lab I am working, THP-1 Cells differentiated by PMA to Macrophage cell just for 24 hour. That is: we add PMA to THP-1 Cells and after 24 hour we change the media and without any delay we also treat the cells by our compound of interest to see changes in the cell signalling. I have read in some papers that I should let the cells to be differentiated for 72hr before doing any next step. what is you idea?

I am having trouble understanding the building blocks of monomers and molecules. Can anyone please validate the following assumptions? 1) A monomer is always a molecule 2) Not all molecules are monomers 3) A polymer is a macro molecule 4) Not all macromolecules are polymers

“Plants are usually charged negatively and emit weak electric fields. On their side, bees acquire a positive charge as they fly through the air. No spark is produced as a charged bee approaches a charged flower, but a small electric force builds up that can potentially convey information. The flower's potential changes and remains so for several minutes". Link My question is: does this account for all plants/trees? And what about other insects than bees? Are there more examples of this electrical attraction between (sea) plants and pollinators?

Hey guys, I'm currently working on a project that is looking at cyanotoxins in soil after irrigation with contaminated waters, and I need a way to test the concentration of cyanotoxins in the soil. With research I have identified methods for testing cyanotoxins in liquid samples (microscopic analysis, ELISA) as well as method for extracting cyanobacteria from the soil (centrifuging with ethanol) however what I cannot find any mention of is a way to extract cyanotoxins from the soil so I can use the aforementioned liquid testing methods. Can any one help me with this? Even just direction to a good source or paper would be much appreciated. Thanks

Can anyone tell me how mitochondria are reproduced and how they engage in cell production? I think I understand that mitochondria have their own SDNA/RNA, how then do they get transferred in sexual and conventional cell reproduction - mitosis and myosis? Do they reproduce in a 'convential' way by compying and replicating RNA? I probably have this all wrong ! thank you Z

Is it possible for a wolf to pee, just because he has to, and not mark its territory by it?

Time travel is a fascinating idea for many people... but until technology allows custom movement of a 3D object across the axis of time, it's not a possible task as we imagine it. I have however been wondering about a more likely way of doing time travel. Which wouldn't send you back to the past, but could instantly take you to the future... at least in your own perception. My curiosity is if it might ever be possible to completely shut down a human body, while keeping each and every organ ready to restore functionality to. The aim would be to stop the person from needing food / water / air, keep organs from wearing out and the body from aging, and most importantly ma…

Are proteins in our body competition with each other? It is known that bacteria in our intestines compete, but regarding proteins I only found here: "RNA transcripts, both protein-coding and non-coding, thus have the ability to compete for microRNA binding and co-regulate each other in complex ceRNA networks (ceRNETs)" Does anyone know more competition in our body?

Isopropyl-beta-D-galactopyranoside (IPTG) is often advertised as being free of dioxane. How important is this? I understand that some strains of bacteria are inhibited by dioxane, but how severe is this problem?

I just realized something that I do not understand, which is kind of embarassing since I have been learning things that are built on this for the past 2 years without ever actually understanding it. An enzyme is nothing more than a catalyst, and any catalyst increases the rates of the forward and reverse reactions proportionally (i.e. enzymes do not alter the equilibria of the reactions they catalyze). So how can there be kinases and phosphatases that catalyze reactions that are reverses of eachother? Wouldn't a kinase dephosphorylate its substrate just as much as it phosphorylates it, and if both a kinase and a phosphatase act by reducting the activation energy of the s…

I'm going to be taking a concepts in biochemistry course, and I'm looking to prepare a little for it. What would be the best places to start? I'm primarily looking for supplementary books to the actual textbook (which I have yet to get), but any learning material would be great.

I have obtained concentrations for 3 unknown proteins through BCA assay. I ran kinetics on a spectrophotometer for each unknown at two different different volumes(5uL and 10uL). We only did 1 trial for each volume for each unknown(6 measurements). We ran out of time to do more and we were having some issues with the substrates. Regardless, I now have to write a report on the experiment. This was a citrate synthase experiment. I have no idea what I am looking for. What I do know is that when we increase the volume of the protein samples the ABS/min goes up. Im assuming I should solve for Km and Vmax, but other than that I have no idea what this means as it relates to c…

Hi, Would someone be able to confirm or correct my understanding of cPKC regulation? cPKCs bind DAG by their C1 binding domain, and bind Ca2+ by their C2 binding domain, and then (this is this bit I'm slightly unsure of), the Ca2+ bound C2 domain can then bind to phosphatidylserine. When all of the aforementioned interactions are satisfied, cPKCs are fully active? Thanks