glycine metabolism & its clinical significance
TRANSCRIPT
Glycine metabolism
Dr Rohini C Sane
Glycine metabolism
1) Non essential amino acids
2) Glucogenic amino acids
FUNCTIONS OF GLYCINE
AMMONIA GLUCOSE
BILE SALTS GLUTATHIONE
CREATINE HEME
DETOXIFICATION OXLATES
SERINE PROTEIN PURINE
GLYCINE
FUCTIONS OF Glycine : ABCDGGHOPPS
Synthesis of Glycine From different biomolecules
Glycine metabolism
1.Synthesis of Glycine from Serine
Synthesis of Glycine from -SerineReversible reaction
Synthesis of Glycine from Threonine
Synthesis of Glycine fromThreonine
Synthesis of Glycinefrom
Glyoxalate
Degradation of Glycine
Degradation of Glycine to Ammonia &CO2
Role of THF in Glycine Metabolism and Ammonia synthesis
Degradation of Glycine to Ammonia &CO2
Role of THF in Glycine Metabolism
Role of Glycine in synthesis of Cysteine
Role of Glycine biosynthesis of molecules
Glycine links many Metabolic pathways & biomolecules
Functions of Glycine: Collagen synthesis1. Collagen –rich in Glycine -30%
Functions of Glycine :Formation of purine ring2.Formation of purine ring : N7
Functions of Glycine -3.Synthesis of Glutathione
Functions of Glycine in Detoxification by conjugation reaction
4.Detoxification by conjugation reaction
• Bile acids cholic acid /cheno cholic acid
• Cholic acid + Glycine Glycocholic acid
• Chenodeoxy cholic acid+ Glycine Glyco- cheno deoxy cholic acid
• Benzoic acid +Glycine Hippuric acid (excreted by kidney )
Functions of Glycine in synthesis of Heme
5.synthesis of Heme
Succinyl CoA + Glycine δ Amino levulinate (ALA )
HEME
ALA SYNTHTASE
Synthesis of Heme from Glycine
Functions of Glycine: Biosynthesis of Creatine
Source of EnergyIn muscles
Excretion in urine
Creatine & creatinine : clinical significance
Creatine Creatinine
Serum 0.2 -0.6 mg/ dl 0.6 -1.0 mg/ dl
Urine 0 – 50 mg/day 1 -2 gm /day
Creatinine estimation–KFT ( CREATININE –ENDOGENOUS ,NOT ABSORBED NOR SECRETED SECRETION,DAILY EXCRETION )
Creatinine coefficient - mg / kg body weight / dayMan - 24-26 mg / kg body weight / dayWoman - 20- 22 mg / kg body weight / day
Creatnuria : muscular dystrophy /Diabetes Mellitus / Hyperthyroidism/ starvation
Arginine ,Glycine & Methionine (SAM)involved insynthesis of Creatine
Metabolic disorders of GlycineGlycinuria
• Serum Glycine concentration is normal/increased in excretion of Glycine in urine ( defective renal reabsorption of Glycine )
• Increased formation of urinary oxlate calculi (stones )
Primary hyperoxaluria
Increased formation of urinary oxlate calculi
↓
oxalosis ( deposition in various tissue )
Generally defective Glycine transaminase
+ impairment in Glyoxalate oxidation to Formate
Vitamin B12 deficiency :Increased formation of urinary oxlate calculi(stones ) corrected by Vitamin B12 supplementation
Glycinuria :Metabolic disorders of Glycine
Role of Glycine in oxalate formation
Primary Oxaluria type Ileads to renal /kidney stone formation & is responsible for mental retardation
Kidney stones ( Calcium oxalate )
Hepatocytes of liver are involved inOxalate synthesis & renal cells are Involved in oxalate excretion
Summary Of Metabolic pathways of Glycine