Which of these steps in Kreb's cycle indicates substate level phosphorylation

Options

A. Conversion of succinic acid to `alpha` - ketoglutaric acid
B. Conversion of succinic acid to malic acid
C. Conversion of succinyl Co. A to succinic acid
D. Conversion of malic acid to oxalo acetic acid

Answer

C

Explanation

Succinate thiokinase catalyzes the conversion of succinyl COA to succinic acid. During this step COA is released and one molecule GTP is formed fromGDP . This is a substrate level phosphorylation. GTP Is converted to GDP with the simultaneous synthesis of ATP fromGDP .