Methods for enhancing phytase thermal stability by fusing binding elements to target phytases are provided. Engineered phytases that include binding elements fused to target phytases to cause cyclization of the engineered phytases and enhance thermal stability of the target phytases are described. Engineered nucleic acids encoding engineered phytases and hosts engineered to express engineered nucleic acids are also provided. Methods for incorporating engineered phytases in animal feed and animal feed including the same are described.