L-arginine, citrulline and pyrimidine derivatives including orotic acid, uridine, uridine 5-monophosphate (UMP), cytidine and cytidine 5-monophosphate (CMP) are produced using a bacterium belonging to the genus Escherichia harboring a mutant carbamoylphosphate synthetase in which the amino acid sequence corresponding to positions from 947 to 951 in a wild type carbamoylphosphate synthetase is replaced with any one of amino acid sequences of SEQ ID NOS: 1 to 9, and feedback inhibition by uridine 5-monophosphate in the bacterium is desensitized.