1. Noun. (biochemistry) The semiquinone derived from ubiquinone ¹
¹ Source: wiktionary.com
Medical Definition of Ubisemiquinone
1. Small molecule with a hydrocarbon chain (usually of several isoprene units) that serves as an important electron carrier in the respiratory chain.
The acquisition of an electron and a proton by ubiquinone produces ubisemiquinone a free radical), a second proton and electron convert this to dihydroubiquinone. Plastoquinone, which is almost identical to ubiquinone, is the plant form.
This entry appears with permission from the Dictionary of Cell and Molecular Biology
(11 Mar 2008)