Bacteria More Virulent in Microgravity

Tortured Potato writes "Did you know that salmonella become more virulent in simulated microgravity? No one's sure why, either. Professor Cheryl Nickerson of Tulane University is hoping to find out why when an experiment with brewer's yeast gets sent up on a Russian Progress rocket to the Space Station next year."

Comments

This isnt the smartest question ever posed...

[hookedup]

Would it's ability to be more virulent possibly come from it's relative ease of travel with no gravity? Like somehow gravity 'slows' the virus down when it's on the planet or something...ok...this is where i trail off...

Go gentle on me.

Re:This isnt the smartest question ever posed...

[Oddly_Drac]

"ok...this is where i trail off..."

Relax, you still got insightful.

"it's relative ease of travel with no gravity"

Or bifurcation in three dimensions being a darn sight easier than in two dimensions and lacking any downward pressure on the cytoplasm meaning that a simple organism can redirect resources to it's primary function, reproduction...

Empiricism gets really silly when they start going for the showy experiments. For example, is this limited to Salmonella, or do all bacteria show the same increase in virulence?

Re:This isnt the smartest question ever posed...

[supertsaar]

Hmmm. I think these really-really small bacteria suspended in a liqiud medium don't care too much about the gravity. You know, they are so small the impact of individual molecules makes them shake. (see Brownian movement Yet we see these effects, apparantly....(I'd really like to see these effects being reproduced by another group) I don't think its that simple somehow....

Volunteers needed?

[flagweb]

May I be the first to volunteer to test the Brewers Yeast in space. Preferably in its fermented liquid state. I am especially interested if the space trip is free (as in Beer).

Space...the next brewery

[krypticide]

Soon the biggest occupant of near space will be giant breweries, with giant pipes connecting them to the ground to feed beer-lovers all over the world.

Simulated Microgravity?

[roshi]

Anyone care to enlighten me as to what "Modeled Microgravity" is exactly? How do you simulate u-G?

Just wondering...

Re:Simulated Microgravity?

[Oddly_Drac]

"But if you're going to assay the virulence of microorganisms, it stands to reason that you have to have them in micro-gravity for at least one round of cell division"

You're not wrong, but one method is through electronic suspension of liquids...another is using shearing forces on rotating cylinders.

I'd look for references, but I'm on my way home. ;)

Re:Simulated Microgravity?

[roshi]

I see. Did a bit of digging on my own. So the key point here is preventing the cells from accumulating on the bottom of a vessel and thereby forming unnatural multi-cell structures. You can't erase the acceleration on each individual cell (which is probably negligable anyway) but you can mitigate the collective effects, so the cells are "more micro-gravity like" in their conglomorate behavior.

Still not convinced that cells in a rotating bio-reactor are a good model for cells in an in vivo micro-gravitational environment, but at least "modeled micro-graviity" makes sense now!

Re:Relating to the layperson

[roshi]

I can't help myself....
From m-w.com:

Main Entry: virulent
Pronunciation: -l&nt
Function: adjective
Etymology: Middle English, from Latin virulentus, from viruspoison
Date: 14th century
1 a : marked by a rapid, severe, and malignant course b : able to overcome bodily defensive mechanisms
2 : extremely poisonous or venomous
3 : full of malice : MALIGNANT
4 : objectionably harsh or strong
- virulently adverb

Virulent, as applied to bacteria, refers to its propensity to a) multiply quickly b) infect a host efficiently and c) cause deleterious effects. It has nothing to do with that other "virulentas"-derived word, "virus" beyond sounding the same and sharing an etymological root.

There is no ambiguity or incorrectness in referring to a bacteria (or bacterial disease) as "virulent." It is, in fact, a very specific and technically correct term. (eg, one can and must talk about virulent vs benign strains of E. coli).

All that being said, you are dead right that the mean lay understanding of basic bio is woeful, though I would suggest that perhaps we need a Feynman, not an Asimov, but beggars can't be choosers, right?

This brings the question...

[shadwwulf]

...if less gravity makes bacteria more virulent, does more than 1x g's cause the bacteria to become less virulent? If so I wonder if we'll be seeing medical equipment down the road that flattens you to a spinning wall much like a specific type of amusement park ride of today does.

All in the name of curing a bacterial infection...

Just a thought...

Re:This brings the question...

[Idarubicin]

Come on, folks. Insightful? The parent post was being Funny. I hope.

High g forces will kill a bacterium. One technique sometimes used in biology labs to extract the content of cells is centrifugation--fifteen thousand gees for a handful of minutes will crush most cells and let you get at the goodness inside.

This technique is not recommended for killing bacteria inside a living person, however. Pulping patients is a practice generally frowned upon by the medical profession.

The few gees that a healthy person could withstand on a continuous basis aren't enough for a bacterium to even notice.

Artificial Gravity

[kippy]

What I would like to know is why more research isn't being done on artificial gravity. So many of the health problems encountered in LEO gravity cound be sidestepped if you just spin the damn craft.

I would love to know why some of the effort being spent on watching things get sick in 0g isn't being directed to something as simple as spinning a glorified beer keg in orbit with some mice in it.

Can someone tell me why this isn't being done?

prediction

[theMerovingian]

an experiment with brewer's yeast gets sent up on a Russian Progress rocket to the Space Station next year

Next slashdot article:
Germans initiate a new space program, volunteer additional funding for the ISS.

Re:Relating to the layperson

[Scrameustache]

The world of biology needs an Asimov in my opinion.

It had one, his name was Isaac Asimov: Phd in microbiology.

Now you know : )

Dumb question

[Mothgoul]

If you could initiate negative g's, what would happen to the yeast? Sour beer?

Re:Control in a centrifuge?

[Carnildo]

3 to 3.5 Gs, unless the Russian rockets are a lot harder on their occupants than US rockets are.

Re:Simulated Microgravity? From the article

[G4from128k]

How do you simulate u-G?

You use a rotating test chamber as shown in a figure from the fulltext. By rotating the chamber, gavity never acts in the same direction for very long and nothing settles out of solution. A second rotating chamber is oriented to let gravity work, while duplicating the effects of spin.

Personally, I am skeptical that bacteria really experience gravity. Bacteria are too small -- at that scale most "fluids" are effectively the consistency of molasses in January. I wonder if something as simple as light impacted their experiment. We shall see.....