Test 37- BC Flashcards
Biotin acts as CO2 carrier for what enzymes
carboxylation enzymes
pyruvate > OAA
pyruvate carboxylase
Acetyl CoA>
malonyl CoA
Acetyl-CoA carboxylase
priopionyl CoA> methylmalonyl CoA
proprionyl CoA carboxylase
excess ingestion of avidin
biotin def
requries thyiamine cofactor
transketolase
alpha keto DH
pyruvte DH
most abundant AA in collagen
collagen is 1/3 lysine!!
what AA i smost avidly consumed by fibroblasts?
glycine
aa in collagen
GLYCINE
proline
lysine
Poor feeding developmental delay megaloblastic anemia (decreased DNA) high plasma homocysteine pt can't form cobalamin
can’t synthesize…
methionine
results in homocystinemia d/t impaired mehthionine re-synthesis
B12 def
homocysteine mehtyltransferase requries B12 as a cofacgor
enzyme that contributes to pigment stones
arise secondary to infection of biliary tract> release of beta glucuronidase by injured hepatocytes/bacteria>
hydrolysis of bilirubin>
increaes amt of unconjugated bilirubin
principle stabilizing force for secondary structure of proteins (beta pleated sheets)
H bonds
primary structure
peptide bonds
secondary structure: alpha helix/B sheet
H bond
How does hyperammonmia affect the glutamate/glutamine cycle?
Excess NH4> depeletes alpha keto>
inhibition of TCA
depletes glutamate>
accumulation of glutamine>
astrocyte swelling/dysfxn
exertional dyspnea
pneumonia
acute chest syndrome
recurrent abdominal pain
sickle cell
point mut leading to sub of glutamic acid for valine
sickle cell
niemen pick enz def
sphingomyelinase>abnormal accum phospholypipid sphinomyeline
Methylmalonic acidemia
defect in isomerization rxn that transforms methylmalonyl coA to succinyl CoA prior to succinyl co A entering TCA cycle
inhibition of LDH in exercising muscle> inhibition of glycolysis d/t intracellular depletion of what substance?
NAD!
how do we regenerate NAD in anaerobic conditions
NADH transfers H to pyruvate to form LACTATE
required to convert glyc 3 P to 1,3 PBG
NAD
agent that specifically blocks the interaction of ITP w/ its intracellular receptor would ecrease the activity of?
Protein kinase C
what activates PKC?
DAG and Ca release from SR under influence of IP3
Gq
phospholipase C
Dag/IP3
PK C
Ca> smooht muscle contraction
causes of secondary lactase def
viral gastroenteritis/disease taht damges inetstinal epithelium
beta galactosidase
needed to confert Lactose to galactose
OAA forms kaspartate while reacting w/ glutamate. What is needed for htis rxn?
B6 transamination
occurs between AA and alpha keto acid
transamination
cells that have LOW potential to replicate and LOW telomerase activity
pancreatic beta cells
neurons
myocardial cells
no potential to divide
RBC
telomerase is present in…
cancer cells
stem cells
epithelilial cells (rapidly divide)
N acetylglutamate
essential activity of CPI
snRNPs
synthesized by RNA pol II
help remove INTRONS/syntehsis of mRNA
insulin>
TK>
stimulate synthesis of glycogen/proteins, fatty acids by activating…
protein phosphatase
Why is HbS more severe than HbC
HbS contains valine in place of glutamic acid. this promotes hydrophobic interaction among Hb molecules> plymerization of HbS moleucles>
RBC distortion
lipoic acid is needed for what enzymes?
Mitochondrial enzymes:
PDH> lactic acidosis
alpha ketoglutarate DH
branched chaint ketoacid DH> maple syrup urine disease
EDsyndrome is associated w/ abnormal
collagen
mild hypochormoic microcytic anemia w/ increased HbF, HbA and target cells
beta thalassemia
what causes beta thalassemia?
mut in defective trxn
processing
translation of beta globin mRNA
what occurs outside of the osteoblast during collagen synthesis?
terminal propeptides cleaved by N and C procollagen peptidases> tropocollagen
formation of collagen fibrils
covalent cross links formed by lysyl oxidase
why do bruises get a greenish color?
heme oxygenase
Accident> bruise> lysis of RBC> release of Hb into soft tissues> heme degraded to....
heme oxygenase converts heme to biliverdin to form a BRUISE!
Map kinase singal transduction pathway includes…
Ras proteins>
g protein that is exists in active and inactive forms–GDP vs GTP
BER
corrects defects in single bases
glycosylase removes defective base corresponding sugar phosphate cleaved and removed by endonuclease lygase dna Pol replaces missing nucleotides ligase reconnects DNA strand
BER
