Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Metabolism > Metal metabolism > Flashcards

Metal metabolism Flashcards

(64 cards)

Start Studying
1
Q

loop of geomicrobiology

A
  • geosphere minerals undergo bacterial leaching of metal ions
    = biosphere proteins
  • biosphere proteins undergo bacterial deposition of metal ions
    = geosphere minerals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what metal is debatably essential

A

chromium

  • difficult to demonstrate deficiencies because of ethics.
  • haven’t found a reason that it is essential
  • however it is present, suggesting that it might be
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

essential metals of focus

A

Mn
Fe
Cu
Zn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

how much Zn is present in a 70kg human body

A

2-3g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how much Cu is present in a 70kg human body

A

100mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

how much Fe is present in a 70kg human body

A

3-5g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how much Mn is present in a 70kg human body

A

12-20mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

functions of metals in proteins

A
  • catalytics; 50% enzymes require metals
  • structural; tertiary, quaternary, quinary
  • regulatory
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is quinary structure of proteins

A

different types of proteins coming together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the different ligands of metal in proteins

A

N: Hist
O: Glu, Asp
S: Cys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what does N ligand stand for

A

Hist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does O ligand stand for

A

Glu, Asp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does S ligand stand for

A

Cys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

method of identifying if protein has metal-binding sites

A

looking at the spacing of the amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

example of a kown Zn proteinase

A

Thermolysin found in bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

example of a putative Zn proteinase

A

LTA4 hydrolase found in human)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

mining sequence database

A
  • structural genomics. search for 3D structure of metalloprotein (protein database PDB)
  • determine liganvd signatures
  • search for homology in sequence database
  • find putative metalloprotein (curator)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is the indirect method whih predicts the sizes of human metalloproteins

A

mining sequence database

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what % of entire proteome is non heme Fe

A

1.1%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what % of entire proteome is Cu

A

0.3%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what % of entire proteome is Zn

A

10%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what % of entire protoeme is Mn

A

?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

how do ligand interactions differ between metals

A

as you move down the periodic table, ionic radius increases and coordination numbr increases
= weaker ligand interactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is the function of Na+ and K+

A

they are minerals needed for nerve conductions. Need proteins to maintain electrochemical gradietnq

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
sodium requirements
2.3g/day
26
potassium requirements
4.7g/day
27
sodium and potassium inside cells
Na+: 12mM | K+: 140mM
28
sodium and potassium outside cells
Na+: 140mM | K+: 5mM
29
function of Mg2+
- cofactor - enzyme complexes e. g ATP is nearly always a magnesium complex
30
what is ATP nearly always a complex of
Magnesium complex
31
Essentail trace metals
``` Mn Fe Co Cu Zn Mo ```
32
when is Ni essential
good bacteria in the gut need Ni
33
what is Mo
molybdenum - only 4 enzymes in humans with Mo - pterin cofactor binds Mo
34
Use of Co
- only 2 enzymes in humans (methylmalonyl-CoA, methionine synthase) - Is the centre of vitamin B12 structure - vitamin B12 = cobalamin
35
Uses of Mn
- Mn deficiency is uncommon - too much Mn causes Manganism = Parkinson's - total number of Mn enzymes is unknown (mitochondiral superoxide, dismutase, arginase, pyruvate decarboxylase)
36
Uses of Ni
only 9 enzymes, but none have been identified in the human body. Good bacteria found in the gut need Ni
37
Cu uses
- deficiency causes Menkes disease = fatal - overload causes Wilson's disease = treatable with chelating agen of Zn supplementation - dozens of human Cu enzymes (superoxide dismutuase, cytochrome C oxidase) - mostly found as Cu+ because intracellular environment is highly reducing - metallochaperones prevent free radicals being formed
38
cuprous
Cu+
39
cupric
Cu2+
40
what prevent formation of free radicals
metallochaperones
41
what controls mammalian intracellular copper homeostasis
- tightly controlled by transporters and metallochaperons
42
uses of Fe
- redox active which gives most of its functions: - 250 non-heme proteins - oxgen transport and activation - many proteins - overload and deficiency can occur
43
ferrous
Fe2+ = active iron
44
ferric
Fe3+ = storage iron
45
what is the state of active iron
Fe2+, ferrous
46
what is the state of storage iron
Fe3+, ferric
47
how is Fe2+ found
- in Fe/S clusters - bound to heme - non-heme Fe; mononuclear and dinuclear
48
examples of heme iron proteins
- hemoglobin - myoglobin - cytochomes - peroxidase - catalase - heme-binding proteins (sensors and transporters)
49
when does iron redox recycling occur
aerobic iron metabolism
50
process of iron redox recycling
- iron is outside of enterocyte in intestine as Fe3+ - Dcytb on membrane reduces iron to Fe2+ - Fe2+ transported across membrane via DMT1 - most of iron stored in cell as Ferritin - remaining exported as Fe2+ via Fpn - Fe2+ is oxidised again outside cell by Hp - Fe3+ binds to Tf for transportation in blood
51
Tf
transferrin = transport protein
52
Ft
ferritin = storage protein
53
DMT1
divalent metal transporter 1
54
Dcyt b
duodenal cytochrome b
55
Hp
hephaestin
56
Fpn
ferroportin
57
what is ferritin
- complex proteon with an iron mineral core, where iron is storoed as on oxide - iron oxidase acitivity - once iron has been oxidised, it migrates to the core for storage, hence iron core
58
what is transferrin
- uses Fe3+ - binds two Fe3+ from intestine cell and transport to blood where needed - has two biding sites - transferrin uptake by cells is by receptor mediated endocytosis
59
transferrin receptor
- two irons bind to receptor - pit forms an endosome to enter cell - endosome is acidified to release iron into cell - protein recyled to surface, both Tf and Tf receptor
60
what happens to iron during cyctochrome P450 reaction cycle
goes to very high oxidation state: Fe5+
61
inborn errors of Cu metabolism
Deficiency: copper deficiency, Menkes disease Overload: copper toxicity, Wilson's disease
62
inborn erros of Fe metabolism
deficiency: iron deficiency overload: iron toxicty, primary iron overload disorders: hemchromatosis (HFE1-4), aceruloplasminemia, atransferrinemia, hemosiderosis
63
inborn errors of Zn metabolism
deficiency: acrodermatitis enteropathica overload: zinc 'toxicity'
64
Which one of the following elements is believed to be non-essential
aluminium

Metabolism (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions