Test 28- BC Flashcards
negative G
Free energy of products is LOWER than that of substrates
favors PRODUCT formation
positive G
free energy of products is HIGHER than substrates
favors SUBSTRATE formation
Deletion/insertion of a number of base pairs (nucleotides) that are NOT multiples of three (126> 124 bp)
FRAME SHIFT MUTATION
alter reading of genetic code> non functional proteins
MC CFTR mutation
codon deletion of phenylalanine at position 508
**also possible to get frameshift mutation caused by 2 bp deletion in the CFTR protein
codon deletion
deletion of one or more entire codon (genetic triplet code)
amatoxin
found in poisonous mushroom
Inhibits RNA pol II halting mRNA synthesis
(RNA pol II makes mRNA, largest> MASSIVE)
pathology that occurs secondary to x linked mutation affecting the PRPP synthetase gene leading to an INCREASED substrate concentration
Gout
occurs in pts w/ activating mutations involving PRPP synthetase>
increased production/degradation of purines
first line therapy for treating acute gouty arthritis
NSAIDS
right knee pain and swellling caused by gout should be treated w/ a drug that targets what type of cells
NSAIDS> inhibit COX> exert braod anti-inflammatory effect> inhibits neutorphils
acute gout drug taht inhibits neutrophil chemotaxisa nd phagocytosis by preventing microtuble formation
colchicine
def of neutral aa trasnporters in proximal renal tubular cells and on enterocytes
Hartnup Disease (specifically TRYPTOPHAN)
niacin def
loss of dietary tryptophan (Hartnups disease)
ataxia
episodic erythematous and pruritis skin lesions
loose stools
niacin def
inhibits initiation of protein synthesis by binding to and distoring structure of prokaryotic 30S ribosome
Streptomycin–STOPS initiation complex formation and causes misreading of MRNA by binding to the 30S subunit
gentamicin neomycin amikacin tobramycin streptomycin
interfere w/ binding of aminoacyl tRNA to A site
Tetracyclines (tRNA site)
elastin’s plasticity and ability to recoil is d/t
interchain crosslinking involving lysine
contains unusual nucleosides like pseudouridine and thymidine
tRNA
what sequence is at the 3’ end of tRNA and is used as a recognition sequence by proteins?
CCA
3’ hydroxyl group of the CCA tail is used as a binding site for the AA
TATA box
upstream promoter region (TFs bind here to initate unwinding and separating of DNA)
maturation process of precursor mRNA
addition of poly A tail at 3’ end
methylguanosine cap at 5’ end
removal of introns
what happens if a tRNA is mischarged w/ the incorrect AA
incorporates WRONG AA into growing polypeptide chain (no proof reading during protein translation)
maple syrup urine disease is caused by a def in what enzyme
alpha ketoacid DH
what coenzymes does alpha ketoacid DH require?
Tender loving care for nancy
Thiamine (B1) Lipoate Coenzyme A Fad NAD
what treatment can improve sxs of a pt w/ maple syrup urine disease
high dose thiamine
folate def inhibits formation of dTMP, limiting DNA synthesis, promoting megaloblastosis and erythroid precursor cell apoptosis.
what type of supplementation can REDUCE erythroid precursor cell apoptosis
thymidine
increases dTMP levels
rate limiting enzyme in the urea cycle
carbamoyl phosphate
what actiavtes carbamoyl phosphate
NAG
where do nitrogen atoms in the urea molecule come form?
NH3
aspartate
enz def in homocystinuria
cystathione synthase
ectopia lentis (dislocated lens)
intellectual disability
marfanoid habitus
High risk for tromboembolic episodes
Homocystinuria
tx for cystathione synthase def
50% of pts respond to high doses of B6 if issue is w/ decreased affinity of CS for B6
how is splenic hypertrophy related to pyruvate kinase def
PK def causes hemolytic anemia d/t failed glycolysis (not enough ATP to maintain RBC)>
spleen must work harder to remove erythrocytes from circulation
newborn w/ lethargy, vomiting, hypotonia
Metabolic acidosis + hypoglycemia
Increased concentration of propionic acid in urine
Proprionic acidimia caused by def in priopionyl CoA carboxylase
Priopionyl Coa is derived from AA (val, ile, met, Thr), odd numbered FA and cholesterol side chains
Lynche syndrome
AD
abnormal nucleotide MMR
(MSH2, MLH1)
location of PPP
cytoplasm
b oxidation, ketogenesis, citric acid cycle, parts of urea cycle, pyruvate carboxylation
LCOATION?
mitochondria
transketolase
enzyme of PPP that uses B1 as a cofactor
pyruvate carboxylase
initial step in gluconeogenesis
converts pyruvate to OAA
Ornithine transcarbamoylase
Ornithine and CP are combined to form citruline
succinate dehydrogenase
enzyme of TCA converts succinate to fumarate
HMG CoA lyase
mitochondrial enzyme responsible for ketogenesis from HMG CoA
homeobox genes
DNA binding TF that play important role in morphogenesis
hypoglycemia after prolonged fasting w/ LOW levels of ketone bodies
MCAD
acyl CoA DH
Hepatomegaly, cardiomegaly, macroglossia, hypotonia and mental retardation
Polysaccharide accumulation in lysosomes
POMPE Disease
alpha glucosidase def leads to glycogen accumulation in lysosomal vesicles
responsible for breaking down small mats of glycogen
severe neurologcial abnormalities d/t high blood and tissue ammonia levels + increased orotic acid excretion (d/t accumulated carbamoyl phosphate)
OTC def
female w/ recurrent abdominal pain and anxiety that improves after IV heme preparation
increased gamma-ALA (causes sxs) and porphogiilinogen d/t over activation of ALA synthase ( usually inhibited by heme)
