Biochemistry Flashcards
which substance is decreased in acetaminophen intoxication allowing the damaged of liver injury and why?
- Glutathion→ detoxifies free radicals
and peroxides.
Is the fundament of treatment with N- acetyl cysteine
which is the cause of I cell disease?
Defect in N-acetylglucosaminyl-1-phosphotransferase - failure of the Golgi to phosphorylate mannose residues (FAILURE IN TARGET)→ accumulation of serum levels lysosomal enzymes
Tell 8 symptoms of Scurvy
- petechiae
- poor wound healing
- hemarthrosis
- anemia
- swollen gums
- bruising
- perifollicular and periosteal hemorrhages
- weakened immune response
Alkaptonuria
AR Deficiency of homogentisate oxidase-- degredative pathway from tyrosine to fumarate accumulate homogentisic acid in tissue benign dark pigment in tissue--- sclerae, urine artharlgias
Homocystinuria vs Marfan sx
- Homocystinuria: Cystathione synthase deficiency, -intelectual disability, thrombosis. Marfanoid habitus
- Marfan sx: Fibrillin -1 gene mutation: No intelectual disability, no thrombosis.
Mc Ardle disease
AR
Glycogen storage disease— deficiency of glucogen phosphorylase (myophosphorylase) degrades glycogen in glycogen 1 phosphate (impaired muscle glycolysis)
Exercise intolerance – muscle pain and cramping
Dopamine Beta Hydroxylase deficiency
impaired sympathetic adrenergic activity
Infants: Hypotension, failure to thrive and hypothermia
Adults: postural hypotension, exercise intolerance, nasal cogestion and ejaculatory problems.
Which is the main characteristic of G- coupled receptors?
7 transmembrane hidrophobic alpha helical domain
Median chain acyl coa dehydrogenase deficiency
AR
disorder in fatty acid oxidation– decreased the ability to break down fatty acids into acetyl CoA
Hypoketotic hypoglycemia
lethargy, seizures, coma and liver disfunction (hematomegaly)
MODY
maturity onset diabetes of the young: AD, impaired insulin secretion, minimal or no effects in insulin action.
mutations in GLUCOKINASE (regularory role in pancreatic cells to insulin secretions) gene or transcripction factors—— Hyperglycemia is mild, as no longer need medication.
The only purely ketogenic a.a
lysine and leucine
essential a.a
- methionine
- valine
- histidine
- threonine
- isoleucine
- phenylalanine
- tryptophan
- leucine
- lysine
Glucogenic a.a
- methionine
- valine
- histidine
N- acetyl synthase deficiency
required cofactor carbamoyl phosphate synthase I
Absence of N- acetylglutamate—- hyperammonemia
neonates: poorly regulated respiration and body temperature, poor feeding, development delay, intellectual disability
Identical presentation of carbamoyl phosphate synthase I deficiency
Which enzyme is increased as a result of Lesch Nyhan syndrome
Phosphoribosyl pyrophosphate amidotransferase increased it activity because accumulation of uric acid leading increased production of purines.
Vit A toxicity
Acute: nausea, vomiting, vertigo and blurred vision
Chronic: alopecia, dry skin, hepatic toxicity, hepatomegaly, papilledema (pseudotumor cerebri) benign intracranial hypertension
teratogenic: cleft palate, cardiac abnormalities
AUG, UAG, UAA, UGA
Initiation codon (methionine) stop codons Do not code for a.a or bind to tRNA When the ribosome encounters a stop codon --- releasing factor protein-- bind to the ribosome--- dissolution ribosome/mRNA coupling
In porphyrin synthasis
the rate limit enzyme is ALA synthase (cofactor B6)
tRNA structure
- 3´ CCA— acceptor stem
- D loop— proper aminoacyl tRNA synthase
- Anticodon loop—- bind to mRNA codon
- T loop—- TyC sequence —binds to ribosome
Glucagon functions by…
bind to G protein receptor coupled—- increasing cAMP intracellular—- activating protein Kinase A
B12 vitamin es a cofactor
- conversion of methylmalonic acid to succinyl coA (Fatty acid metabolism) — the accumulation of methylmalonic acid damage myelin
- Homocysteine to methione (as methal donor)
Hormone sensitive lipase
In adipose tissue catalyses the movilization of TAG into free fatty acids and glycerol
Activated by Catecholamines, glucagon and acth
inhibited by insulin
biotin
B7
cofactor
- Pyruvate carboxylase: pyruvate to succinil coA (gluconeogenesis)
- Acetyl CoA carboxylase: Acetyl coA to malonyl coA (fatty acid syntehsis)
- Propionyl coA Carboxylase: propionyl Coa to Methyl malonyl coA (fatty acid oxidation)
Propyomelnocortin POMC
Polypeptide precursor produce:
- beta endorphins
- ACTH
