Does linezolid affect klebsiella?

It is a very strong antibiotic used when the others haven't helped. However, it works for gram-positive not gram negative bacteria. Klebsiella is gram negative. They do have some results that say it will work for a few gram negative bacteria but klebsiella isn't one of them. Its also extremely expensive and is an mao inhibitor which carries this warning too: Instruct patient to avoid foods and beverages with high tyramine content. Review common foods known to have high tyramine content (eg, aged cheeses, fermented or air-dried meats, red wines, sauerkraut, soy sauce, tap beers).
If you have an infection that absolutely nothing else has helped its probably worth a try, just be aware of the problems associated with the drug.