Failure notification with multiple profiles
SQL Server will use the default mail profile on alerts. On the otherside if you need to specify a special mailaccount or some other error handling, just create a step in your job which will be executed in the case of an error which uses sp_sendDbMail to send the alert.

If you just want to change the alert sender for ALL of your jobs, you can change it by right clicking your sql server agent, select properties, alert system and there you go. See here.