Metabolism of galactose: Classic Galactosemia, Galactokinase deficiency

📌 𝐅𝐨𝐥𝐥𝐨𝐰 𝐨𝐧 𝐈𝐧𝐬𝐭𝐚𝐠𝐫𝐚𝐦:-   / drgbhanuprakash  
📌𝗝𝗼𝗶𝗻 𝗢𝘂𝗿 𝗧𝗲𝗹𝗲𝗴𝗿𝗮𝗺 𝗖𝗵𝗮𝗻𝗻𝗲𝗹 𝗛𝗲𝗿𝗲:- https://t.me/bhanuprakashdr
📌𝗦𝘂𝗯𝘀𝗰𝗿𝗶𝗯𝗲 𝗧𝗼 𝗠𝘆 𝗠𝗮𝗶𝗹𝗶𝗻𝗴 𝗟𝗶𝘀𝘁:- https://linktr.ee/DrGBhanuprakash

Metabolism of galactose: Classic Galactosemia, Galactokinase deficiency

Galactose is a monosaccharide sugar that is a C-4 epimer of glucose.

Principally there are 2 enzymes involved in the metabolism of galactose, they are galactokinase (GAL-K) and galactose-1-phosphate uridyltransferase (GAL-T). Note there are also UDP-galactose-4’-epimerase (GAL-E) and mutarotase (GAL-M) which are involved in the process but are less clinically significant.

Dietary galactose enters glycolysis/gluconeogenesis by first being phosphorylated to galactose-1-phosphate by galactokinase. This enzyme is present in many tissues but is most active in the liver.

Clinical correlation: A deficiency of galactokinase leads to non-classical galactosemia, a rare and mild galactosemia.

The galactose in galactose-1-phosphate is then transferred to UDP-glucose by galactose-1-phosphate uridyltransferase to yield UDP-galactose and glucose 1-phosphate. UDP-galactose is then converted back to UDP-glucose by GAL-E and the cycle repeats.

Clinical correlation: A deficiency of galactose-1-phosphate uridyltransferase leads to the genetic disease Classic Galactosemia, which is a severe disorder if not caught early by infant screening.

#galactosemetabolism #galactose #biochemistry #galactosemia #galactokinasedeficiency #medicalstudents #fmge #usmlepreparation #drgbhanuprakash #mbbslectures #neetpg #usmleprep #usmlestep1 #usmle #galactose