Can I power down a USB port?

A remote webcam is connected to a USB port. It works well most of the time, but after a few weeks one color channel stopped working. Pulling the USB plug and re-inserting fixed the issue.

This leads to my question: I can access the computer which is connected to the camera with ssh. Can I switch off (and on) just one USB port temporarily in order to reset the camera? Or is USB power hard wired? Remote rebooting the computer does not help.

I think the USB 5V line is hardwired.