USB, Firewire, Express Card on separate busses?

[Mierk]

I use my 2.53 MBP (unibody) in my recording studio and am using both usb ports, firewire port, display port, as well as an express card SATA interface at the same time. I was curious if any of those interfaces utilize the same buss or access to the processor...or in other words, does the fact that I am running some peripheral device off of each port slow down the ports themselves? I am trying to get the best performance possible and want to make sure I am not slowing down the express card port by having something plugged in to the USB port. Thanks!