Its possible i suppose, but not likely. It would be more likely that it were the other way around - misfiring can clog cats. Try swapping the plug and wire to see if the misfire moves to the cylinder that you swapped them to. If it doesnt move, check for spark from the coil pack. If everything is good then check the injector by removing the plug from the cylinder and crank the engine over a few turns and see if you can smell fuel coming from the cylinder. If everything is good so far then id say that your cats are so plugged up that its choking the engine.
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