[otrs] changing the email address of ticket notifications

I've set up a gmail account for receiving and sending tickets to our OTRS system. But ticket notifications to agents get sent out from another address -- the default otrs@shambhala.org address. Email from our server gets marked as spam a lot (our server team are volunteers, and have no time to deal with spam issues), so ticket notifications are being marked as spam, or are delayed in delivery. Is there any way to change the email address that ticket notifications come from? I looked around in the Admin section and also in the Admin manual, but couldn't find any info. Best, Greg