BioMed Realty has landed two new life science tenants for its newly repositioned Sidney Research Campus at 200 Sidney St., 40 Erie St. and 21 Erie St. in Cambridge. The new tenants of the space, formerly inhabited by Vertex Pharmaceuticals , are CRISPR Therapeutics and Synlogic Inc. CRISPR, a biopharmaceutical company that's pioneering genome-editing technology to make medicines for serious diseases, will lease 19,817 square feet of lab and office.