Basic Metallo-biology Flashcards
(29 cards)
What % of proteins in cells have a metal bs
50%
What is a structural example of metal use
Zinc finger proteins which need zinc to bind 4 residues and allow for dna-protein interaction and protein-protein
(See fr)
Which metal is in the human superoxide dismutase active site
Copper
What does sod do
Concerts superoxide radicals to hydrogen peroxide for ox stress
Which enzyme converts urea to ammonia and co2 in plants fungi and bacteria
Urease
What has it got in its active site
Di nickel site
Why is ammonia important
For n source for growth
And also in h pylori it neutralises ph in stomach
Which metals are used for electron transporting
Redox metals eg fe
Which enzyme uses 2 heme fe to transport electrons to oxygen in last resp step
Cox
Give example of zinc finger uses
Dna recognition, txn activation, protein folding/assembly
Which large epigentic complex has a zinc finger domain and why
Cbpp300 to bind other tf
What is the motif called on a lot of tf which is zinc dependant dnabd
Dm motif
What does the dm motif recognise
Minor dna groove
Why chaperone is used to transfer copper to sod
Ccs1
What redox metals were available in the reduced environment with anaerobic bacteria years ago
Fe and cu because soluble in reduced environment (not in oxidised)
Is there ions in sea water
No it’s metal limiting
Which metal is seen as a relic as no human proteins use it due to lack of availability and
Nickel (only in some bacteria and plant urease’s)
What is the fe acquisition evolved mech
Reductases comcert fe3 to fe2 (soluble and can be transported into cell)
Siderophorws in fungi/bacteria bind fe3 and allow transportation
What does cambialistic mean
When enzyme can use 2 metal substrates depending on what available
Which metals not used in eukaryotes but are in pro
Cobalt and nickel
How can non biological metals like cadmium and mercury cause toxicity
Bind to protein and block it’s function
Displace other metals eg cadmium displaces zinc from zinc finger
How can they bind just as well
Cysteine and histidine residues in proteins hve high metal ion affinity
What was the Minamata disease
Methyl mercury exposure led to binding to selleno proteins in brain causing oxidative damage
Eg muscle weakness, vision liss
What enzyme can cadmium bind and block causing ox damage
Sod
