Biochem Halo-halo 4 Flashcards
fructose 2,6 bisphosphate in regulation of glycosysis in the liver
❌allosteric inhibitor of PFK-1
❌ cleaved to triose phosphates in the glycolytic pathway
❌ its formation is catalyzed by a glycolytic enzyme
✅ provides an intracellular signal that’s sensitive to changes in blood glucose levels
DOPA enzyme and cofactor
DOPA decarboxylase
vitamin B6
end-products of beta oxidation
NADH
FADH2
acetyl-coa
what enz converts OAA to PEP in gluconeogenesis
PEP carboxykinase
enz defective in orotic aciduria
UMP synthase
drugs that cause lupus
Hydralazine
isoniaizid
procainamide
phenytoin
etanercept
methyldopa
sulfa drugs
fabry disease
hypohydrosis
remarks on glycogen phosphorylase
produce glucose-1-phosphate
isocitrate dehydroganase will yield
α-ketoglutarate
amino group + _________ = alanine
pyruvate
general properties of nucleic acids
negatively charged at physiologic pH
absorbs UV light at wavelength 260 nm at pH 7.0 (due to the conjugated double bond of purine and pyrimidine nucleotide
3’5’ phosphodiester bond
3’ hydroxyl group of sugar of 1st mononucleotide is linked to 5’-phosphoryl group of 2nd mononucleotide
3 scientists who worked together on studying the structure of DNA
James Watson
Francis Crick
Rosalind Franklin
Despite the efforts of Franklin, she will never win a Nobel prize because she had died of ovarian cancer in 1958 and the Nobel committee does not consider posthumous candidacies
watson-crick’s DNA model
right-handed (clockwise) double-stranded DNA helix
what’s with the G-C bond?
3 hydrogen bonds
remarks on Grooves of the DNA
Grooves often act as sites of DNA-protein interaction needed for regulation of gene expression
DNA-protein itneraction is via hydrophobic interaction and ionic bonding
remarks on Z-DNA
12 base pairs per turn
Longger and thinner
LEFT-handed
seen in 5’ end of chromosomes
first level of organization of DNA
2 nm DNA double helix
remarks on 10 nm chromatin fibril
beads on a strong appearnce on EM
consists of †NUCLEOSOME separated by linker DNA (H1)
DNA is wrapped 1.75x (nearly twice) over a histone octamer in left handed helix
†nucleosome is composed of 146 base pair-DNA
remarks on 30 nm chromatin fibril
solenoid
group of nucleosomes
remarks on chromosomes
condensation of DNA occurring during PROPHASE of mitosis
23 pairs of chromosomes
22 pairs of autosomes
1 pair of sex chromosomes
*review: Z-DNA is seen in 5’ end of chromosomes (left-handed, 12 base pairs per turn, longer and thinner)
uncoiling of chromatin is facilitated by
HAT
histone acetyltransferase
gene silencing is facilitated by
methyltransferase found in CpG islnads MOA 1. physically impede transcription proteitns? 2. MBDs —> more gene silencing (methyl CPG binding domain)
condensation of chromatin is facilitated by
histone deacetylase
(HDAC)
decreases transcription
ribosomal RNA is what % of total rna
80%
most heterogenous RNA
mRNA
unusual bases seen in nucleosides in tRNA
dihydrouridine
pseudouridine
inosine
ribothymidine
levels of DNA organization
2 nm DNA double helix 10 nm chromatin fibril 30 nm chromatin fibril supercoiled structure chromosome
