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makaveli8x8
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Magnets a way to fight contam?
#7996023 - 02/08/08 12:15 PM (16 years, 1 month ago) |
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So some bacteria cell walls are positive charged while others are negatively charged, which is why certain stains are used when trying to view them under a microscope.
Is it possible to use a magnet to keep the bacteria at the very bottom, purhaps even keeping them from moving?
is it possible this is what makes stirplates so effective with LC's?
-------------------- We were sent to hell for eternity Øh® We play on earth to pass the time Over-population the root of all Evil-brings the Elites Closer to the gates.
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MycoAu
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Re: Magnets a way to fight contam? [Re: makaveli8x8]
#7996210 - 02/08/08 01:13 PM (16 years, 1 month ago) |
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No, magnets won't help in this case. In general terms, a magnet may sound like it would have an effect, but the other forces at work are much stronger than the charges in the cell walls acting with a magnet. Look up the term "dipole moment" and read a little bit. Then see if you can find a good site talking about the dipole moment in a cell wall. In addition to the weakness of that force in relation to everything else, you have shielding effects from the water in your LC.
And BTW, the stirbar in the LC makes it work wonderfully b/c it keeps the water agitated (causes better gas exchange for the mycelium) and reduces the local concentrations of by-products around the mycelium.
Long-->short: It won't work.
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makaveli8x8
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Re: Magnets a way to fight contam? [Re: MycoAu]
#7996676 - 02/08/08 03:14 PM (16 years, 1 month ago) |
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yeah i looked that up and about had a brain hemorage
the thing sticking in my head is the ability of cell walls to repel stains, while letting others in based on the polarity of the cell walls.
it just seems like it would have to be a pretty strong magnetic feild to do that.
so i don't know much about it ill take your word that the cell wall won't react with magnets, but perhaps their is a magnetic stain that could be obsorbed into bacteria cells that would react?
this might be offtopic, but i searched for moving cells with magnets and came up with this, not sure if it applys to what im talkin about as it causes my brain to bleed
http://www.bio-magnetics.us/technology.html
it sounds like its pretty new tech at the least maybe someone will find the new tech interesting
-------------------- We were sent to hell for eternity Øh® We play on earth to pass the time Over-population the root of all Evil-brings the Elites Closer to the gates.
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MycoAu
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Re: Magnets a way to fight contam? [Re: makaveli8x8]
#8001882 - 02/09/08 07:01 PM (16 years, 1 month ago) |
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I didn't read the whole link- though it was interesting. The basic idea behind that website "idea" is:
-You create beads (or they do) that are magnetic.
-These beads also have a surface that allows the particular cell type you're trying to cultivate/propagate to grow and, most importantly, adhere to the bead (preferentially over the other surfaces available to it within the confines of the media/well/plate- such as the well/plate walls.)
-Because the cells preferentially adhere to your beads, the majority of your growth is on those beads.
- Because the beads are magnetic and can be removed by a magnet (with a thin film membrane over the magnet- and therefore is replaceable at low cost- read: disposable)
- The beads, being removable and having the largest portions of growth can either be pulled from the well/plate and placed into a new well/plate- OR- can be held in the current well/plate while old media is siphoned off and new media is added without loss of cells and/or major disruption of the cell layer on the beads.
- So, if you wanted to develop a magnetic bead with the right nutes to grow mycelium on.....
This doesn't necessarily help with the contam issue though. Even if you manage to find a way to preferentially bind the bacteria/other contams without binding the mycelium in any large amount (which I doubt considering the relative cell concentrations)- some cells of the contam will be left behind. This isn't a 100% removal method, only highER levels of removal/binding. And that 1 cell or 1000 cells of contam that are left behind will quickly (probably less than 24 hours) propagate and leave you back at step one.
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RogerRabbit
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Re: Magnets a way to fight contam? [Re: MycoAu]
#8002143 - 02/09/08 07:42 PM (16 years, 1 month ago) |
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Stir plates help by oxygenating and agitating the water. Simple sterilization will destroy bacteria. It can't contaminate your grains or LC unless it's introduced later. RR
-------------------- Download Let's Grow Mushrooms semper in excretia sumus solim profundum variat "I've never had a failed experiment. I've only discovered 10,000 methods which do not work." Thomas Edison
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makaveli8x8
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Re: Magnets a way to fight contam? [Re: RogerRabbit]
#8003188 - 02/09/08 11:42 PM (16 years, 1 month ago) |
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yah i guess i should have put "help make it effective" in my question
the reason i started thinking about all this thow is to my knowledge its near impossible to have a 100% clean culture(which myco recently stated as well), so when a person goes to inclinate an LC their could be trace amounts of bacteria and over time causes it to go bad.
So thats what lead me to thinking it would be cool if their was a way to pull all the contam to the bottom somehow, which would allow the mushroom to grow a little more freely above it, purhaps faster
-------------------- We were sent to hell for eternity Øh® We play on earth to pass the time Over-population the root of all Evil-brings the Elites Closer to the gates.
Edited by makaveli8x8 (02/09/08 11:43 PM)
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MycoAu
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Re: Magnets a way to fight contam? [Re: makaveli8x8]
#8003634 - 02/10/08 03:49 AM (16 years, 1 month ago) |
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If you want decent cultures, repetition is king. Practice won't make you perfect, but it'll definitely help. And you'll find that with a small amount of foresight, you can avoid contamination in almost all cases. I recently cloned an oyster on agar in open air, no washed hands or table. I torn open the mushroom of interest, flame sterilized a knife, cooled it in 3% peroxide that was poured into a non-sterile jar I had available and cut out my peices. The only "good technique" I used was being quick with actual placement of tissue on the plates. The plates weren't left open for more than 3-5 seconds apeice. 19 of 20 plates grew uncontaminated. Not bad I'd say. *mycoau toots own horn*
In any case, practice your technique. If you spend 1/4 the time developing your techniques and practical skills as you do searching this website and trying to find ways around contamination in the "perfect way", you'll find that you didn't need to go searching in the first place. (not meant to be offensive, just an observation- However, I do like the way you're thinking. very intesting stuff)
BTW, LC is just as forgiving in my experience.
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makaveli8x8
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Re: Magnets a way to fight contam? [Re: MycoAu]
#8005717 - 02/10/08 05:59 PM (16 years, 1 month ago) |
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yah i don't have much problem with agar but LC's just have an eery look to them(when i was first starting out i had lots of contams with LC's).
With agar the mushrooms can grow over the contam and fight it but it can't do that as well in an LC.
The main thing that started this thread was the fact that I ran across a few websites talking about stains for microscopy, coupled with the fact that im about ready to jump back into LC's.
anyways i guess using magnets this way just isn't possible
-------------------- We were sent to hell for eternity Øh® We play on earth to pass the time Over-population the root of all Evil-brings the Elites Closer to the gates.
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Yrat
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Re: Magnets a way to fight contam? [Re: makaveli8x8]
#8007965 - 02/11/08 08:53 AM (16 years, 1 month ago) |
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Are you referring to the classification terms of bacteria, gram-positive vs gram-negative? If you are, these terms do not represent actual charges of the bacterial cells.
Instead, they are names given to describe the differences in cell wall composition between classes of bacteria. Gram-positive means that the bacteria have many more layers of peptidoglycan in their cell wall, making it much thicker and able to "trap" crystal violet dye during a Gram stain (see Gram stain: http://en.wikipedia.org/wiki/Gram_stain). Gram-negative bacteria have a much thinner cell wall with a different composition, allowing the dye to be washed away, instead showing the counter-dye under a microscope.
-------------------- "There are a thousand hacking at the branches of evil to one who is striking at the root." -Henry David Thoreau Strike The Root
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MycoAu
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Re: Magnets a way to fight contam? [Re: Yrat]
#8008702 - 02/11/08 12:47 PM (16 years, 1 month ago) |
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No, that's not what he was refering to. Because of the way cell walls are made (the types and arrangements of the chemicals associated with the composition of most cells walls), the entire cell wall carries a minute, overall charge. Depending on the particular chemicals and their amounts, the wall can be slightly positive or slightly negative. Refer to the term dipole-moment and look up some stuff regarding the natures of these polar bonds (and materials depending on the particular application of the word).
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Yrat
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Re: Magnets a way to fight contam? [Re: makaveli8x8]
#8008814 - 02/11/08 01:25 PM (16 years, 1 month ago) |
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I am very familiar with chemical charges and dipole moments, but when the OP said this:
Quote:
makaveli8x8 said: some bacteria cell walls are positive charged while others are negatively charged, which is why certain stains are used when trying to view them under a microscope.
he is definitely referring to Gram staining, and not chemical charge.
-------------------- "There are a thousand hacking at the branches of evil to one who is striking at the root." -Henry David Thoreau Strike The Root
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makaveli8x8
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Re: Magnets a way to fight contam? [Re: Yrat]
#8009026 - 02/11/08 02:30 PM (16 years, 1 month ago) |
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ok to clear up, I read about this in negative staining. Im not sure if it applys to gram positive and gram negitive i just assumed it did.
Here's the gist of what i read regarding negative staining.
These stains color the background and not the cells because, the negative charge of the cell wall and the negative charge of the stains repel each other.
A thing im not sure about is if its just certain stains and certain cells this applys to
i trust my source pretty strongly over wiki regarding negative stains, but in reflect errors can be anywhere.
-------------------- We were sent to hell for eternity Øh® We play on earth to pass the time Over-population the root of all Evil-brings the Elites Closer to the gates.
Edited by makaveli8x8 (02/11/08 02:34 PM)
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Yrat
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Re: Magnets a way to fight contam? [Re: makaveli8x8]
#8009090 - 02/11/08 02:43 PM (16 years, 1 month ago) |
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makaveli,
i have a background in microbiology and have done countless Gram stains. i'm not sure if you might have been confused regarding the terminology of negative and positive staining. this indeed has to do with the composition of the bacterial cell wall, but is totally unrelated to charge. in fact, i have never heard of a staining method that uses an overall charge of the bacteria. so you are saying there is a stain that colors the background and NOT the cell?
-------------------- "There are a thousand hacking at the branches of evil to one who is striking at the root." -Henry David Thoreau Strike The Root
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makaveli8x8
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Re: Magnets a way to fight contam? [Re: Yrat]
#8009120 - 02/11/08 02:49 PM (16 years, 1 month ago) |
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yes its called "negative staining"
kind of like a negative photograph, used mostly for shape and size of cells, used when cells don't stain well, and when you don't want to use harsher stains that damage the cell
-------------------- We were sent to hell for eternity Øh® We play on earth to pass the time Over-population the root of all Evil-brings the Elites Closer to the gates.
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fastfred
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Re: Magnets a way to fight contam? [Re: makaveli8x8]
#8016251 - 02/13/08 02:15 AM (16 years, 1 month ago) |
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I don't think that first paper is really all that relevant.
Anyhow a magnet will not attract living cells regardless of their charge. A charge only generates a magnetic force when it is in motion. The static electrical properties of the cells won't cause it to be attracted to a magnet.
Another static electric charge can attract oppositely charged cells to it, but that's not a magnet. And it would be pretty complicated, requiring high voltage power supplies and the like.
-FF
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millar
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Re: Magnets a way to fight contam? [Re: fastfred]
#8024290 - 02/14/08 08:09 PM (16 years, 1 month ago) |
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Would this be at all related to the technique, I think it's called electrophoresis, where charge is used to separate charged portions of a sample? Seems I heard about that being used in DNA research, they use a sample on agar or something similar, and the charge breaks up molecules and the ions migrate towards the electrodes.
Don't remember details so I guess I should look it up, but I would imagine the ratio of molecular weight to charge would cause even particles with the same polarity to fraction out in a similar manner to paper (etc.) chromatography.
Still, I don't think it's useful here, but it sure is interesting.
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MycoAu
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Re: Magnets a way to fight contam? [Re: millar]
#8024510 - 02/14/08 08:56 PM (16 years, 1 month ago) |
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Some of the basic principles of electrophoresis are the same as what is being discussed here, though I think that there is major confusion between net charges, ions, dipoles and few others related, but completely separate ideas/terms. And yes, these are very interesting topics that have absolutely amazing and incredibly diverse uses.
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