Create Java objects from multiple sources - configurable deployments

I have some classes (Teacher, Student...) and I want to create objects from them with fields backed from more database sources in a configurable way. The information where the data source is for a particular class field can be different depending on deployment (configuration of the App). I want to have the information about database sources persisted as well. (I use Hibernate for persisting.)

Example of deployment 1:

• Teacher.firstname should be persisted from LDAP
• Teacher.lastname should be persisted from LDAP
• Teacher.email should be persisted from PostgreSQL
• Student.firstname should be persisted from PostgreSQL
• Student.lastname should be persisted from LDAP
• Student.email should be persisted from PostgreSQL

So there needs to be also information persisted in some DB that Teacher.firstname is backed in LDAP, Teacher.email in PostgreSQL etc.

Example of deployment 2:

• Teacher.firstname should be persisted from PostgreSQL
• Teacher.lastname should be persisted from PostgreSQL
• Teacher.email should be persisted from PostgreSQL
• Student.firstname should be persisted from PostgreSQL
• Student.lastname should be persisted from LDAP
• Student.email should be persisted from PostgreSQL

So there needs to be also information persisted in some DB that Teacher.firstname is backed in PostgreSQL, Student.lastname in LDAP etc.

I use Spring (not only) for DI and JPA (Hibernate) for persistency, but it's not so important. I am not looking for an answer how to configure 2 datasources in Spring/JPA, but rather how to design that problem generally.