Making bacteria express green fluorescent protein - could it decrease fitness?

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Simfish
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Since it obviously takes energy and extra amino acids to express the green fluorescent protein, so it's possible that bacteria expressing GFP might have slightly lower fitness (on average) than bacteria that aren't expressing GFP.

I'm sure the effect is negligible in most cases. But maybe these is some research that shows this? And are there borderline cases where this effect might not be negligible?
 
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Simfish said:
Since it obviously takes energy and extra amino acids to express the green fluorescent protein, so it's possible that bacteria expressing GFP might have slightly lower fitness (on average) than bacteria that aren't expressing GFP.

I'm sure the effect is negligible in most cases. But maybe these is some research that shows this? And are there borderline cases where this effect might not be negligible?

I think that being fluorescent might be more of a drawback than just taking more energy. Being highly visible even to primitive eyespots can't be a good thing if you're a bacterial colony. I don't believe that you'd notice a trend that you could be sure was due to metabolic stress, and not some other factor. I can't find studies for viability of GFP in engineered organisms, but that just says nobody bothered to check.

In the lab, they live, but I think it's safe to say that in the wild it's too complex to know how that would work. Maybe that gene confers some protection we don't know about?
 
Simfish said:
Since it obviously takes energy and extra amino acids to express the green fluorescent protein, so it's possible that bacteria expressing GFP might have slightly lower fitness (on average) than bacteria that aren't expressing GFP.

I'm sure the effect is negligible in most cases. But maybe these is some research that shows this? And are there borderline cases where this effect might not be negligible?

I'm sure the transformed bacteria would be outcompeted by wildtypes; I have to keep my transformed epithelial cells separated from my 'wildtypes' as well. But that's not really the point- GFP (or GFP fusion proteins) are used to study protein dynamics.

I wonder how the GloFish do- the ones that can be bought as pets?
 
It depends on how strongly the protein is expressed. It can reduce the growth rate to zero in extreme cases. If one strain outgrows another by 1%, the first population will be about 2.7X the second in 100 generations (assuming none die).