Nucleotides Flashcards
nucleotides vs nucleoside
nucleotides include 1 or more phosphates
purines
adenine, guanine. hypoxanthine
pyrimidine
cytosine thymine and uracil
what are the functions of nucletides
active precursors of DNA
NAD, FAD, and CoASH have a nucleotide part
ATP and GTP are important energy molecules
the high energy donors contain nucleotides (UDP glucose)
cAMP in signal transduction is a cyclic nucleotide
many enzymes are controlled by cell’s level of adenosine nucleotides
What amino acids are required for purine synthesis
glycine, glutamine, aspartante
phosphoribosyl pyrophosphate PRPP
catalyzes rxn that includes ribose 5 phosphate + ATP to add on another phosphate
what is donated with PRPP and PPi goes out?
ribose 5 phosphate
what kind of atom is donated with glutamine goes in a glutamate comes out?
nitrogen
what atom is donated with formyl tetrahydroflate goes in and tetrahydroflate comes out?
a carbon
what kind of atom is donated with aspartate goes in a a fumarate comes out?
a nitrogen
what is IMP
inosine monophosphate
inosine is …
hypoxanthine attached to a ribose
what are the precursors that donate components for the de novo synthesis of pyrimidine nucleotides
asparate and glutamine
PRPP is required in purine or pyrimidine synthesis?
pyrimidine
carbamoyl phosphate synthetase 2 (CSP 2)
involved in urea cycle its in the cytosol
what must orotate react with in order to form a pyrimidine nucleotide?
PRPP
how does uracil turn into cytosine
gains a nitrogen from glutamine
thymidylate synthetase -
Thymidylate synthase is an enzyme that catalyzes the conversion of deoxyuridine monophosphate to deoxythymidine monophosphate.
serine hydroxymethyl transferase
Serine hydroxymethyltransferase is a pyridoxal phosphate dependent enzyme which plays an important role in cellular one-carbon pathways by catalyzing the reversible, simultaneous conversions of L-serine to glycine and tetrahydrofolate to 5,10-Methylenetetrahydrofolate.
dihydrofolate reductase
Dihydrofolate reductase, or DHFR, is an enzyme that reduces dihydrofolic acid to tetrahydrofolic acid, using NADPH as electron donor, which can be converted to the kinds of tetrahydrofolate cofactors used in 1-carbon transfer chemistry.
