Yes cooking food at 400 F degrees will kill bacteria that can be in the food.
Most bacteria and germs in food will only be able to survive temperatures up to 140 F.
This is the reason you want to cook meats and other food that can contain bacteria using a temperature of at least 160 F.
Most meat is fully cooked when the internal temperature of the meat reaches 160 F or above.
If the meats internal temperature is under 160 F or under 140 F then bacteria may still be in the meat.
So make sure you cook the meats to an internal temperature of 160 F to kill bacteria that can make you sick.
Salmonella is also killed when you cook the food including eggs all the way.
So even if an egg has Salmonella which is rare then as long as the eggs are cooked fully and they are not runny then there should be no bacteria or salmonella in the eggs.