Menaquinone Biosynthesis: The Mechanism of 5,8-Dihydroxy-2-naphthoate Synthase (MqnD). Academic Article uri icon


  • MqnD catalyzes the conversion of cyclic dehypoxanthine futalosine (6) to 5,8-dihydroxy-2-naphthoic acid (7) and an uncharacterized product. This study describes a chemoenzymatic synthesis of 6. This synthesis achieved a 2-fold yield enhancement by using titanium(III) citrate as the reducing agent and another 5-fold yield enhancement using a fluorinated analogue of dehypoxanthine futalosine (5) that was converted to 6 by an ipso substitution mechanism. This synthetic route enabled the synthesis of 6 in sufficient quantity to identify the second reaction product and to determine that the MqnD-catalyzed reaction proceeds by a hemiacetal ring opening-tautomerization-retroaldol sequence.

published proceedings

  • Biochemistry

author list (cited authors)

  • Manion-Sommerhalter, H. R., Fedoseyenko, D., Joshi, S., & Begley, T. P.

citation count

  • 0

complete list of authors

  • Manion-Sommerhalter, Hannah R||Fedoseyenko, Dmytro||Joshi, Sumedh||Begley, Tadhg P

publication date

  • June 2021