Random Biochem Facts

arne1's version from 2015-10-01 16:21


Question Answer
GABA is formed by the decarboxylation of Glutamate
Histamine is formed bythe decarboxylation of Histidine
Tryptophan turns into into 5-Hydr-Trp (hydroxylation). Then a CO2 comes (decarb) off to form serotonin
The catecholaminesdopamine, norepinephrine and epinephrine are formed from tyrosine
tyrosine turns intodopamine.Tyrosine is hydroxylated to dihydroxy-phenylalanine (L-DOPA) •L-DOPA is decarboxylated to dopamine
collagen has abundance ofglycine, proline, lysine. glycine in each third position. Lysine used extracellular for covalent cross-linking of different collagen molecules
in collagen formation which two enzymes need vit Cprolyl- and lysyl hydroxylase
residue glycosylated in collage formationhyrdroxylysine
Ehlers-DanlosSyndromes (EDS)mutation of a gene for the pro-a chains of collagen (often Type I, III, or V collagen)
OIabnormal collagen of Type I collagen, often a mutation displacing a glycine by serine or cysteine. Type I mildest, type II most severe. Thin sclera makes them blue..
Aspirinacetylates a serine gorup on the active site of COX thus irreversibly inhibiting it. endothelial prostacyclin can overcome (anti coagulant). But thromboxane formed in lower amounts.
suicide inhibitorallopurinol. Allopurinol is used to irreversibly inhibit xanthine oxidase (produces urate which then leads to crystals). The enzyme itself uses the drug allopurinol and forms the irreversible inhibitor alloxanthine (oxypurinol). Alloxanthine binds very tightly to a molybdenum-sulfide complex in the active site which is needed for catalysis.
Caffeine and theophylline inhibitphosphodiesterase (breaks phosphodiester bond). Inhibitors of PDE can prolong or enhance the effects of physiological processes mediated by cAMP or cGMP by inhibition of their degradation by PDE.
NO activatescytosolic guanylate cyclase. In response to low calcium levels, guanylyl cyclase synthesizes cGMP from GTP. cGMP causes smooth muscle relaxation..
EtOH abuseAST/ALT >2.
Serum markers that measure biliary excretionALP (most specific), g-glutamyl transpeptidase (GGT) and conjugated bilirubin
bone isozymeALP-2
Pancreatitis leads toelevated serum lipase and serum amylase. if aclohol induced pancreatitis, serum lipase/amylase>2
Padget's disease would show highserum ALP-2
VLDLliver to cell
LDL: cell to liver
Question Answer
Sphingomyelin is formed fromphosphatydil-choline (PC) - provides surfactant for the alveoli.
Double bonds beyond which carbon cannot be formed by animals?9
FAs are named by counting from themethyl end. First double bond encountered is the omega (however, the COOH carbon is C number 1). In 18:2, first number is carbons, second is number of double bonds.
High affinity transportersGLUT 1,3,4
Low affinity transportersGLUT 2 and 5
GLUT 1in RBC (high affinity). Also in BBB and kidney.
GLUT 2lowest affinity. works to take high glucose levels to liver. uniporter (facilitated transport) 2 liv(er) crew
GLUT 3high affinity. dominant in neurons and brain.
Glut 4high affinity. insulin dependent. in heart, fat, skeletal muscle.
hereditary GLUT-1 deficiencymicrocephaly, early seizures, then ataxia and impaired speech
GLUT 5low affinity for glucose and high for fructose.
Sodium ion glucose transporter (SGLT)secondary active transport. Na come in along with gucose. uniporter.
SGLT-1found in intstinal mucosal cells for uptake of glucose and galactose
SGLT-2renal tubules. uptake of glucose. (think: renal 2-bules--> SGLT-2).
CFTRcystic fibrosis transmembrane conductance regulator. CFTR is a ligand-gated chloride ion channel controlled by phosphorylation.. type of ABC transporter (inside to outside). It is found in airway ducts, pancreatic duct, reproductive duct, intestinal lumen. The CFTR will open after phosphorylation and Cl- will flow with the gradient into the extracellular space. (mio/sec)
Exception to CFTR release of Cl outside the bodySweat gland: CFTR allows reuptake of Cl- ions from secretory duct into epithelial cells. This reuptake is impaired in CF patients --> salty skin.
CFTR mutation3 bp deletions. loss of phenylalanine at codon 508 (delta-F508).
Copper is an impartant cofactor forlysyl oxidase (cross linking of collagen and elastin)
Acute/chronic pancreatitistrypsin abnormally active in pancreas --> activates other zymogens. proteases and phospholipase A2 will destroy the proteins and the phospholipid membranes of the pancreas. Cause is EtOH abuse. Serum lipase/amylase >2
Bile is conjugated withglycine and taurine (negative charge at duodenal pH). requires ATP and CoA. CoA can react with either glycine or taurine (which is derived from cysteine). This forms amides, aka conjugated bile salts.
In intestinal mucosal cells, glu and gal are taken up viaSGLT-1 Na+ cotransport
AMP is converted to ATP byadenylate kinase
lactosegalactose and glucose
Maltoseglucose and glucose
Pyruvate dehydrogenaseconverts pyruvate to ACoA via pyruvate decarboxylation
Binding of glucagon in liver activatesprotein kinase A --> phsophorylates pyruvate kinase and inactivates it. glycolysis is inhibited and gluconeogenesis can occur.