Type A Blood Converted To Universal Donor Blood With Help From Bacterial Enzyme (sciencemag.org) 44
An anonymous reader quotes a report from Science Magazine: For a transfusion to be successful, the patient and donor blood types must be compatible. Now, researchers analyzing bacteria in the human gut have discovered that microbes there produce two enzymes that can convert the common type A into a more universally accepted type. If the process pans out, blood specialists suggest it could revolutionize blood donation and transfusion. To up the supply of universal blood, scientists have tried transforming the second most common blood, type A, by removing its "A-defining" antigens. But they've met with limited success, as the known enzymes that can strip the red blood cell of the offending sugars aren't efficient enough to do the job economically.
After 4 years of trying to improve on those enzymes, a team led by Stephen Withers, a chemical biologist at the University of British Columbia (UBC) in Vancouver, Canada, decided to look for a better one among human gut bacteria. Some of these microbes latch onto the gut wall, where they "eat" the sugar-protein combos called mucins that line it. Mucins' sugars are similar to the type-defining ones on red blood cells. So UBC postdoc Peter Rahfeld collected a human stool sample and isolated its DNA, which in theory would include genes that encode the bacterial enzymes that digest mucins. Chopping this DNA up and loading different pieces into copies of the commonly used lab bacterium Escherichia coli, the researchers monitored whether any of the microbes subsequently produced proteins with the ability to remove A-defining sugars. At first, they didn't see anything promising. But when they tested two of the resulting enzymes at once -- adding them to substances that would glow if the sugars were removed -- the sugars came right off. The enzymes also worked their magic in human blood. Tiny amounts added to a unit of type A blood could get rid of the offending sugars, they found. The findings have been reported today in the journal Nature Microbiology.
After 4 years of trying to improve on those enzymes, a team led by Stephen Withers, a chemical biologist at the University of British Columbia (UBC) in Vancouver, Canada, decided to look for a better one among human gut bacteria. Some of these microbes latch onto the gut wall, where they "eat" the sugar-protein combos called mucins that line it. Mucins' sugars are similar to the type-defining ones on red blood cells. So UBC postdoc Peter Rahfeld collected a human stool sample and isolated its DNA, which in theory would include genes that encode the bacterial enzymes that digest mucins. Chopping this DNA up and loading different pieces into copies of the commonly used lab bacterium Escherichia coli, the researchers monitored whether any of the microbes subsequently produced proteins with the ability to remove A-defining sugars. At first, they didn't see anything promising. But when they tested two of the resulting enzymes at once -- adding them to substances that would glow if the sugars were removed -- the sugars came right off. The enzymes also worked their magic in human blood. Tiny amounts added to a unit of type A blood could get rid of the offending sugars, they found. The findings have been reported today in the journal Nature Microbiology.
Implausible link. (Score:1)
"After 4 years of trying to improve on those enzymes, a team led by Stephen Withers, a chemical biologist at the University of British Columbia (UBC) in Vancouver, Canada, decided to look for a better one among human gut bacteria."
I'm trying to think of the mental leap from stripping blood to gut bacteria.
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"Some of these microbes latch onto the gut wall, where they “eat” the sugar-protein combos called mucins that line it. Mucins’ sugars are similar to the type-defining ones on red blood cells."
Re:Gut Bacteria (Score:2)
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So UBC postdoc Peter Rahfeld collected a human stool sample and isolated its DNA,
I am willing to bet that he was trying to get rid of some taco from last night. I solve most difficult programming problems while sitting on the throne, it is nice to see biologists share the same method.
Re: Implausible link. (Score:2)
some taco
The use of "some" would suggest that you're either referring to octopus or pussy.
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catalysts
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"After 4 years of trying to improve on those enzymes, a team led by Stephen Withers, a chemical biologist at the University of British Columbia (UBC) in Vancouver, Canada, decided to look for a better one among human gut bacteria."
I'm trying to think of the mental leap from stripping blood to gut bacteria.
I can't think of any better nanomachines at our reach than bacteria: Functional, modifiable, and already here. Just got to pick the right tool for the job
Those vampire guys are pretty smart (Score:2)
Now, researchers analyzing bacteria in the human gut have discovered that microbes there produce two enzymes that can convert the common type A into a more universally accepted type
People laugh at those guys pretending to be vampires, but it turns out by drinking blood they were getting free compatible blood all along to add to what they had!
Mmmm... Fermented blood! (Score:4, Funny)
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artisan fermented organic blood.
I think this stuff is already available in the Star Trek Universe.
The Klingons call it Blood Wine.
Re:Can you? (Score:2)
Re:Diabetic blood (Score:2)
Re: Mmmm... Fermented blood! (Score:2)
Big Discovery (Score:5, Insightful)
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I think the only logical conclusion, should it be successful, is to do this to all blood and end up with a global generic supply of blood that any can donate to, and anyone can receive from.
The expense would be more than justified, especially if we could apply it in all cases (I'm assuming there will be cases where you want to retain a particular property of the donated blood, but for general transfusions, surgery, emergency rooms, etc. then it would be relevant).
It would be the ideal solution to be able to
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Agree. Such an useful process, and doable with technology from 20-30 years ago, wondering why nobody else attempted it before. I did my molecular biology degree in the 1990s and the tech was available back then.
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There are a LOT more A- CMV- donors out there than there are O- CMV-.
So it can't remove CMV, but it can certainly make CMV- A- blood suitable for a CMV- O- recipient.
Result of the transfusion (Score:2)
Cut to the chase: does this mean my blood will glow if I get such a transfusion?
A possible risk (Score:4, Interesting)
One possible risk concerns me.
The treated blood will almost certainly contain some of the enzymes in question. Injecting it might provoke an immune reaction to them, and thus to the bacterial that produce them. This might knock down their concentration in the gut.
The description of the bacterium sounds like a. muciniphila. Lowered concentrations of it in the intestines is associated with a host of pathologies: Obesity, type 2 diabeties, ...
Re: A possible risk (Score:2)
If the enzyme activity is high enough, maybe you could afford the activity loss that would come with tethering to magnetic carrier beads for easy removal.
Alternatively, you could reduce levels post-treatment with serial washings, although there could be a bit of damage to the product rbcs.