we are converting from MS SQL to PostgreSQL. I have a question about validate users against Acrive Directory instead of using PostgreSQL local users.

We have some projects (~30) and 1-5 users in each project. We have one group in our AD for each project.
We have also groups that gives right to tables in the MS SQL server (one or more tables per group).
Users -> Project groups -> Table Groups

Can we do this in PostgreSQL?
We are using Windows Server 2008R2 and the PostgreSQL 9.2.