The invention disclosed herein relates to methods and materials for producing simvastatin and related compounds such as huvastatin. In particular, the disclosure teaches that variants of the LovD acyltransferase polypeptide can be engineered to exhibit properties that facilitate their use in the production of simvastatin and/or huvastatin. The materials and processes disclosed herein are designed so that fermentation facilities currently producing lovastatin can be converted to producing simvastatin and related compounds with minimal modifications.