#Biochemistery
#Carbohydrate_metabolism
#بوست_رقم (17)
الليلة ان شاء الله ح نتكلم عن
Fructose metabolism
ودي النقاط اللي ح نتناولها:
📌 Dietary sources of fructose.
📌 Importance of fructose.
📌 fructose metabolism.
📌 Genetic disorders.
🌸 Dietary sources of fructose:
Sources: hydrolysis of sucrose.
وبرضو بنلقاهو في ال honey و many fruits and vegtables
🌸 Importance of fructose:
1. Energy production:
15% من ال daily energy بتجينا من ال fructose.
2. Fructose is the main nutrient for sperms.
🌸 Fructose metabolism:
In the liver:
1.Liver contains fructokinase enzyme, which phosphorylates fructose into fructose-1-Phosphate.
2. Fructose-1-P by aldolase B enzyme converted into dihydroxyacetone phosphate + glyceraldehyde.
يعني هنا ح ينتجوا لي ناتجين بواسطة انزيم ال aldolase دا بقسم لي ال F-1-P لاتنين.
3. Glyceraldehyde converted to glyceraldehyde-3-P by Triose kinase.
4. Glyceraldehyde-3-P + Dihydroxyaceton P may undergo:
a. Glucose formation (Gluconeogensis)
ودا ال main pathway .
b. Oxidation to pyruvate (Glycolysis).
In extra hepatic tissues:
ال tissues ديل اللي هم ال muscles and adipose tissue.
يلا هنا م عندنا الانزيم اللي موجود في الكبد اللي هو fructokinaseلكن عندنا ال Hexokinase and other enzymes بتعمل ال metabolism لل fructose بحولو ل pyruvat.
طيب دا كان عموماً كدا يلا نشوف الخطوات بتفصيل اكتر😊👋
1. ال fructose بتحول ل fructose-6-P عن طريق ال Hexokinase في وجود ATP
2. ال F-6-P بتحول ل Fructose 1,6 bisphosphate عن طريق ال phosphofructokinase-1 وبرضو في وجود ATP.
3 ال F 1,6 bisphosphate بتحول ل dihydroxyaceton و glyceraldehyde-3-P عن طريق ال aldolase A .
🔥لو لاحظتو هنا موجود aldolase A ,و في ال liver موجود aldolase B.4
4. آخر حاجه بتحولو لي ال glyceraldehyde-3-P و ال dihydroxyaceton P ل two pyruvate وبعد كدا يحصل ليه oxidation.
In the testis (seminal vesicle) :
زي ماعرفنا ال Fructose هو main nutrient لل sperm ف لو حصل deficiencyفي ال Fructose
Correlates with male infertility.
🌸 Genetic disorders:
1. Essential fructosuria:
Cause: due to deficiency of fructokinase enzyme.
Effect: not serious condition.
2. Hereditary fructose intolerance:
Cause: due to deficiency of aldolase B this leads to accumlation of fructose-1-P.
Effect:
1. Damage of liver and kidney tissues (failure).
2. Inhibition of phosphorylase this leads to inhibition of glycogenolysis and hypoglycemia
تعليقات
إرسال تعليق