< Earlier Kibitzing · PAGE 23 OF 23 ·
|Jul-11-09|| ||TheAlchemist: <Knight13> Hmm, I'm not sure I completely followed everything here :-), anyway, maybe we didn't completely understand each other, the "drugs" I was referring to are molecules, which are usually extracted from plant parts with various solvents (usually organic) and other techniques. "Crude drugs" (I think that's the correct term), however, are raw materials, obtained from plants, animals, etc. They can be used if processed properly (dried, grinded and sieved), for example herbal teas contain various mixtures of crude drugs (e.g. a laxative tea might contain senna leaves, fennel seeds, caraway fruits and peppermint leaves; all of course processed as stated above).|
|Jul-11-09|| ||Knight13: <TheAlchemist> What the hell, I thought you were talking about drugs that were made by the plants already; you just suck them out or something. <In some cases the drug you're interested in can be found in more than one part, but you usually select the one with the highest amount.> See! It made me think that! I was referring to "Crude Drugs" then it seems.|
|Jul-11-09|| ||Knight13: <TheAlchemist> Crap forgot the explanation.|
For the sporophyte question:
You know how in some angiosperms the sporophyte generation coexist with gametophyte? Since angiosperms have dominant sporophyte over gametophyte, I meant to ask that when you're extracting stuff from sporophyte generation do you pick from the sporophyte part or the gametophyte part?
For example, mosses: sporophyte plant rows on top of gametophyte plants and depends on it for survival. (Okay, this is a bryophyte, but you know what I mean).
For the algae question: I believe I was referring to "Crude drugs" so that part is basically answered already by your post. (thx)
And for vegetative propagation... That was meant so that you can take them home, grow them in a lab or something, and get all the stuff you need from them so you don't have to go into the fields. Of course, you can do this with seeds, but was curious if you ever used vegetative propagation.
And for the leaves... Was asking which part is most popular for extracting the desired drugs/molecules.
Hope that helps!
|Jul-11-09|| ||TheAlchemist: Let me start at the end...
<And for the leaves... Was asking which part is most popular for extracting the desired drugs/molecules.> Actually the way it's done is usually just cutting up the leaf and then putting everything into a solvent, which is used for extraction (it's similar when you're preparing tea, you put it in boiling water, whereupon some compounds, like caffeine etc., are extracted into the water). I don't know which part of the leaf usually contains the drug, sorry.
<And for vegetative propagation... That was meant so that you can take them home, grow them in a lab or something, and get all the stuff you need from them so you don't have to go into the fields. Of course, you can do this with seeds, but was curious if you ever used vegetative propagation.>
I suppose it's possible, at school we haven't done anything of the sorts, though, we've hardly done any extraction from plant parts at all, in fact. One thing you have to know here is that though I may make it sound easy and straightforward, little of it is actually done for industrial purposes, for discovery yes, but once you have the molecule you want, you try and optimize it (the chemical structure, which in turn defines the physicochemical properties) and create similar, simpler (for synthesis) molecules.
Again, a classical example would be morphine. Though it's still used a lot, many similar acting substances have been produced, by removing "unneeded" parts of its structure until it was found which parts are truly essential for its action. If you take a closer look at the chemical structures of the natural morphine (http://en.wikipedia.org/wiki/File:M...), the synthetic levometorphan (http://en.wikipedia.org/wiki/File:L...), phenazocine (http://en.wikipedia.org/wiki/File:P...), and all the way to pethidine (http://en.wikipedia.org/wiki/File:P...), tramadol (http://en.wikipedia.org/wiki/File:T...) and methadone (http://en.wikipedia.org/wiki/File:M...), you can notice how the structures got progressively simpler (and thus easier and especially cheaper to sythesize), yet the basic structure was always the same - a quaternary carbon atom (C*) with a benzene ring attached to it, an amine group (N*) and 2 carbon atoms in between C* and N*. I really hope I didn't lose you here :-)
Notice especially the word <cheaper>, since the economic part is hugely important (unfortunately). And extracting drugs from plants is time consuming, inefficient and thus economically unfeasible.
<You know how in some angiosperms the sporophyte generation coexist with gametophyte? Since angiosperms have dominant sporophyte over gametophyte, I meant to ask that when you're extracting stuff from sporophyte generation do you pick from the sporophyte part or the gametophyte part?
For example, mosses: sporophyte plant rows on top of gametophyte plants and depends on it for survival. (Okay, this is a bryophyte, but you know what I mean).>
I'm still not sure what exactly you mean here. As far as I know, angiosperms are almost entirely sporophytes (except the ovula and pollen), so naturally almost anything you take is from the sporophyte part, except if you were using the flower part you would include the gametophyte in it. But even there my guess would be that the gametophyte doesn't include the drug, but that it's in the nectar, or petals, etc.
Regarding the mosses, what exactly is the question here (if any)? :-)
Ok, I hope I was close :-), it's almost 2AM here after all.
|Jul-11-09|| ||Knight13: <TheAlchemist: Regarding the mosses, what exactly is the question here (if any)?> Nahh, no quesiton. It was just an example of what I meant. You answered the question; sorry I didn't know a better way to explain it!|
Yes, your molecules I've examined and it indeed gets progressively simpler. This one http://en.wikipedia.org/wiki/File:T... confuses me: why does it look so differently from the rest? Are those two a mirror image?
And, no, you did not lose me there. I completely understood, think. Recap: create a simpler molecule so that it is easier to make so that it is cheaper since it's very time consuming and inefficient to keep extracting them from plants. The example shows how the organic molecules are simplied so that the unneeded parts can be removed so it's not required to synthesize them together along with the desired and optimized structure.
<Actually the way it's done is usually just cutting up the leaf and then putting everything into a solvent, which is used for extraction > Which means, like you said, inefficient! That mixes up everything, even the unwanted parts! Any idea how they're supposed to separate the desired drug after you put all of them into the solvent?
<I'm still not sure what exactly you mean here. As far as I know, angiosperms are almost entirely sporophytes> Ahh. Well, they do still go through alternation of generation. Wasn't aware of this "mostly entirely [composed of] sporophyte [parts]" until you informed me! I guess that means the better question to ask was "can you get drugs from gametophytes" since it is of small part.
<Ok, I hope I was close> Closer than you think! :-D
<it's almost 2AM here after all.> Man, you must be passionate about this stuff so much that it keeps you up at 2 AM! Gotta thank you for this, even though you said "don't mention it"! *buys you breakfast*
|Jul-12-09|| ||TheAlchemist: <This one http://en.wikipedia.org/wiki/File:T... confuses me: why does it look so differently from the rest? Are those two a mirror image?>|
Yes, they are mirror images, they are called enantiomers (http://en.wikipedia.org/wiki/Enanti...)
Oh, and it's not so much passion, it's more like I couldn't sleep :-)
|Jul-12-09|| ||Knight13: <TheAlchemist>
Microbiology. Wanna know if there's anything you can add!
Viruses. Attachment to the host cell (eukaryote, in this case), injection, infection.
Retroviruses has RNA genome. The eukaryotic host cell does not have any enzymes that make DNA by reading the RNA template. So the virus carries RNA-dependent DNA polymerase to be synthesized during translation.
How does the virus do this? Most of the host cell DNA is junk DNA. The genome blends in with the junk DNA. So the host cell doesn't really detect it as hostile or start to destroy it. (I think)
But think about it: the host cell has never seen this new genome, and it tells the cell to make reverse transcriptase. Isn't that weird? It creates DNA <from> RNA. The ribosomes of the host cell is used for making the enzyme. But the ribosomes are already doing something else!
So how does the host cell handle its own process AND at the same time do whatever the virus wants it to do? And the stuff the virus desires isn't even required by the cell to function; more like making a bunch of junk.
I'm guessing the genome "tricked" the host cell's DNA into thinking that it needs it.
|Jul-12-09|| ||Knight13: <TheAlchemist> And what kind of failed experiment results in a black solution with production of gas? :-O |
|Jul-14-09|| ||TheAlchemist: <And what kind of failed experiment results in a black solution with production of gas? :-O >|
Haha, that's classified, of course. I could tell you, but then I'd have to kill you :-)
Anyway, I missed your previous post, let me think about it and I'll answer later today, hopefully I won't forget :-)
|Jul-14-09|| ||Knight13: <TheAlchemist> Looking forward to it!|
Here's something useful about reverse transcription:
The Retroviral DNA synthesis is dependent on two distinct enzymatic activities of the RT: DNA polymerase that can use either RNA or DNA as a template, and a nuclease called ribonuclease H (RNase H) that is specific for the RNA strand of RNA:DNA duplexes. All of the enzymatic functions required to complete the steps involved in creating the retroviral DNA can be attributed to either the DNA polymerase or RNase H of RT.
Reverse transcription of the viral RNA generates a linear DNA duplex.
Also, retroviruses contain two complete copies of the single stranded RNA genome, so that if one of the genome screws up during reverse transcription there's a copackaged backup.
The viral RNA genome has the structural features of a cellular mRNA, including the 7-me-G cap and a polyadenylated 3' end.
Reverse transcription takes place in a ribonucleoprotein complex that includes RT, diploid RNA genome, and viral proteins.
|Jul-20-09|| ||acirce: Happy birthday, <Knight18>!|
|Jul-20-09|| ||WannaBe: 18!?!? You're now an adult!! :-)
|Jul-20-09|| ||TheAlchemist: Happy Birthday!|
|Jul-20-09|| ||Knight13: K found the answer.
Bascially after the retroviral RNA enters the cell and finishes the reverse transcription in the cytoplasm, it already has its DNA made up <from> RNA.
Now they just need to get the linear-made DNA into the host cell's nucleus and it's done. The viral integrase (IN) is a crucial part of integration.
Depending upon the retrovirus, preintegration complexes (Linear viral DNA, several viral proteins including matrix, reverse transcriptase, nucleocapsid, and IN and at least two cellular proteins, high-mobility-group [HMG-I(Y)] ) either enter the nuclei of nondividing cells through the nuclear pore (e.g., human immunodeficiency virus [HIV]) or wait until the nuclear membrane dissolves during cell division (e.g., Moloney murine leukemia virus [MoMuLV])
Integration occurs in two well-characterized catalytic steps, referred to as end processing and joining, respectively. See http://www.pubmedcentral.nih.gov/ar.... HMG protein family members increase the efficiency of integration in vitro by acting on the donor DNA without forming stable complexes with IN or the LTR IN recognition sequences. HMG proteins have common functional features, including (i) binding to the minor groove of double-stranded DNA; (ii) recognizing DNA structure rather than sequence; (iii) preferentially interacting with bent, supercoiled, or distorted DNA structures; (iv) binding to non-B-form DNA structures such as four-way-junctions and cisplatin adducts; (v) unwinding, bending, and supercoiling DNA substrates in the absence of ATP hydrolysis; and (vi) selectively interacting with other sequence-specific transcription factors as part of gene transcription regulatory complexes.
After the viral DNA is entered into the nucleus as part of the host cell it becomes part of the cell, so whatever that DNA codes for could be made by the cell.
Pretty simple answer, huh, <TheAlchemist> :-).
|Jul-20-09|| ||Knight13: <acirce> Dude, how nice of you!! |
<WannaBe> Thank you so much, man! But I still gonna live as a kid.
<TheAlchemist> With gratitude, you will receive, Mr. Alchemist!
<Benzol> K you win the $10. Easily. :-D
|Jul-20-09|| ||Open Defence: hi Happy Birthday!!!
hope you had a blast
|Jul-20-09|| ||chessmoron: Happy 18th!|
|Jul-20-09|| ||WannaBe: <Knight13> You know, this means I've know you for 5 years! (!?!?!)|
Do you know the lyrics to the Toys 'R Us song??
|Jul-21-09|| ||Knight13: <Open Defence> Hi! Yeah, I did, it was very fun, thanks!|
<chessmoron> Thank you, Chessmoron! CG.com Masters vs. Machines Invitational (2007) was very interesting.
<WannaBe> Yeah, 5 years. And sadly, no, I don't even know how Toys 'R Us begins. Not into toys. :-(
|Jul-21-09|| ||Knight13: For the interested:
Retroviral RNA entry into a target cell begins with binding of the viral surface glycoproteins to specific receptor molecules on cell's outer membrane. It mediates fusion of the lipid bilayers of the cell and viral membranes and allows the genetic material of the virus to be introduced into the host-cell cytoplasm.
The envelope glycoprotein complex of retroviruses includes two polypeptides, glycosylated hydrophilic polypeptide (SU) and a membrane-spanning protein (TM). The SU domain binds to a specific receptor molecule on the target cell. This activates the membrane fusion-inducing potential of the TM protein, and the viral and cell membranes fuse.
Viral particles lacking envelope glycoproteins are noninfectious, and cells lacking a receptor are nonpermissive for viral entry.
|Jul-21-09|| ||WannaBe: <Knight13> The lyrics to Toys 'R Us, begins with: "I don't wanna grow up, I'm a Toy 'R Us kid..." |
You previous post reminded me of it... That's all. =)
|Jul-22-09|| ||Augalv: Happy (belated) birthday <knight13> :)|
|Jul-22-09|| ||Knight13: <Augalv> Thank you!|
<WannaBe> Yeah well I think I promised that I'm gonna be mature on here when I turn 18 but that has been moved to 21.
|Aug-04-15|| ||Knight13: Activated my chessforum in case anyone wants to say something. |
Insults will not be tolerated unless they are directed at me.
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Follow chessgames.com posting guidelines.
|Aug-16-15|| ||Knight13: I was just kidding (in case anyone didn't get it). Say whatever you want, post whatever you want. The only rule goes without saying: follow chessgames.com posting guidelines.|
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