BuddyPress One Database on Two Domains

Is there a way to direct BuddyPress on one site to use the database of another site?

i.e I have BuddyPress installed on ChristianGays.com and ChristianGaysChat.com.

I want my members on ChristianGaysChat.com to be able to access their own and other's member profiles from ChristianGays.com.

I currently have both websites set up so that they are using one database. I believe that I just need to find where to change the database prefix in BuddyPress to make it work.

Would appreciate any help.