Post-Translational Modifications

Front 1

Reversible

Back 1

Disulfide bridge,

Cofactor binding,

Glycosylation,

Phosphorylation,

Acylation,

ADP-ribosylation,

Carbamylation,

N-acetylation

Front 2

Irreversible

Back 2

Cofactor binding,

Proteolysis,

Ubikvitinering,

Peptide tagging,

Lysine hydroxylation,

Methylation

Front 3

Disulfide bridge:

Back 3

a covalent bond formed when the reduced –S-H groups of two cysteine residues react with one another to make an oxidized –S-S- linkage. (1-4)

Front 4

Cofactor binding

Back 4

a small, non-protein molecule or ion that is bound in the functional site of a protein and assists in ligand binding or catalysis or both. Some cofactors are bound covalently, others are not. (1 -13, 2-13)

Front 5

Glycosylation

Back 5

the post-translational covalent addition of sugar molecules to asparagine, serine or threonine residues on a protein molecule. Glycosylation can add a single sugar or a chain of sugars at any given site and is usually enzymatically catalyzed. (1 -13, 3-18)

Front 6

Phosphorylation

Back 6

covalent addition of a phosphate group, usually to one or more amino-acids side chains on a protein, Catalyzed by protein kinases.

Front 7

Acylation

Back 7

is the process of adding an O=C-R* group to a compound.

Front 8

ADP-ribosylation

Back 8

is the addition of one or more ADP-ribose moieties to a protein.[

Front 9

Carbamylation

Back 9

addition of Isocyanic acid to amino acids.

Front 10

N-acetylation

Back 10

covalent addition of an acetyl group from acetyl-CoA to a nitrogen atom at either the amino-terminus of a polypeptide chain or in a lysine side-chain. The reaction is catalyzed by M-acetyltransferase. (1-13, 3-20)

Front 11

Proteolysis

Back 11

Specifik klyvning av en proteas från ett begränsat antal av peptidbindningarna i ett proteinsubstrat.

Front 12

Proteas

Back 12

är en grupp av enzym som katalyserar nedbrytningen av bindningarna mellan aminosyror i proteiner. Reaktionen som katalyseras är en hydrolys. Bindningen som bryts kallas peptidbindning. Proteaser är essentiella i de flesta levande organismer.

Front 13

Ubikvitinering

Back 13

Märker ett protein för nedbrytning i proteasomen.

Front 14

Proteasomer

Back 14

är nedbrytningsplatser för proteiner märkta med ubiquitin. Proteasomer är multiproteiner som består av tre subenheter, en större katalytisk mittenbit och två mindre regulatoriska ändbitar ("tunna med lock"). Nedbrytningen sker "i tunnan" och är ATP-beroende. Nedbrytningsprodukterna, de enskilda aminosyrorna, kan sedan användas t ex för att skapa nya proteiner eller för att utvinna energi. Proteasomer finns i alla eukaryota celler.

Front 15

Methylation

Back 15

modification, usually of a nitrogen or oxygen atom of an amino-acid side chain, by addition of a methyl group. Some bases on DNA and RNA can also be methylated. (3-20)