Biochemistry In humans, rate limiting step of de novo pyrimidine synthesis is: A Aspaate tanscarbamoylase B Carbamoyl phosphate synthetase-II C Dihydro orotate dehydrogenase D Ornithine tanscarbamoylase 💡 Explanation In humans, rate limiting step of de novo pyrimidine synthesis is: ✓ Correct Answer: B. Carbamoyl phosphate synthetase-II