40. Galactose, Fructose, Sorbitol, Uronic acid Pathway Flashcards
phosphorylation of galactose
enzyme
galactokinase
formation of UDP galactose
Galactose-1-P + UDP-glucose -> UDP galactose + glucose-1-P
enz: galactose-1-P uridyl transferase (GALT)
use of galactose as carbon source
UDP-galactose -> UDP- glucose
enz: UPD-hexose-4-epimerase
- this has mild symptoms
- galactosemia and galactosuria
- cataracts in early childhood
galactokinase deficiency
- more severe symptoms
- galactosemia, galactosuria, diarhea. vomiting, jaundice,
- poor growth
- severe mental retardation
- liver damage
- premature ovarian failure in females
classic galactosemia /
galactose-1-phosphate-uridyl transferase deficiency
phosphorylation of fructose
fructokinase/ hexokinase
formation of DHAP + glyceraldehyde
Fructose-1-P -> DHAP + Glyceraldehyde
Enz: Aldolase B
symptoms of fructokinase deficiency/ essential fructosuria
benign
asymptomatic
Hereditary fructose intolerance is deficient of what enzyme
aldolase B
s and sx of
Hereditary fructose intolerance
- profound hypoglycemia and vomiting after consumption of fructose or sucrose
- jaundice
- hemorrhage
- hepatomegaly
- renal dysfunction
- hyperuricemia
- lactic acidosis
- death
- appear after weaning from milk
tx of Hereditary fructose intolerance
eloiminate fructose, sucrose and sorbitol from diet
conversion of glucose to sorbitol requires what enzyme
aldose reductase
aldose reductase are found in
lens, retina schwann cells liver kidney placenta rbc ovaries seminal vesicles
Conversion of sorbitol to fructose
sorbitol dehydrogenase
sorbitol dehydrogenase is found in
liver
ovaries
seminal vesicles
