text: A molecule which inhibits the function of this molecule is mixed with hypoxanthine and thymidine in a culture used to isolate hybridoma cells.
full_question: A molecule which inhibits the function of this molecule is mixed with hypoxanthine and thymidine in a culture used to isolate hybridoma cells. The chemotherapeutic drugs aminopterin and methotrexate are derivatives of this molecule. DHFR converts this molecule to its active form, which contains an additional four hydrogens. Antibacterial sulfa drugs prevent dihydropteroate synthase from synthesizing this molecule. With cobalamin, this molecule participates in many one-carbon transfers such as the conversion of homocysteine to methionine and the conversion of uracil to thymine. Pregnant women are advised to have diets high in this molecules to prevent neural tube defects such as spina bifida. For 10 points, name this molecule, a B vitamin named due its rich presence in leafy greens.
first_sentence: A molecule which inhibits the function of this molecule is mixed with hypoxanthine and thymidine in a culture used to isolate hybridoma cells.