I am planning to use vector pCAL-n to express proteins in E. coli (Stratagene). I would welcome any comment or advice from people having tried one of the pCAL vectors (pCAL-n, pCAL-c, pCAL-kc, pCAL-n-EK) Thank you very much in advance. Daniel MARC INRA - Centre de TOURS 37380 Nouzilly, France marc at tours.inra.fr