Arylformamidase Structure

From MDWiki
Jump to navigationJump to search


The structure of arylfromamidase was obtained from RCSB Protein Data Bank (PDB ID: 2PBL).

The predicted interaction arylformamidase with other proteins was determined using the STRING database (STRING: Search Tool for the Retrieval of Interacting Genes/Proteins).

The DALI database was used for the structural comparison of arylformamidase with other proteins.

PDBsum database was used to determine the secondary structure of arylformamidase.


Structure of Arylformamidase

Figure: Arylformamidase (All Chains)

Arylformamidase the whole protein.PNG

The image above shows the chains A (upper right), B (upper left), C (lower right) & D (lower left) interacting. The molecules in the middle of chains A & B and chains C & D is phosphate ion (PO4). The green molecule between chain B & D is a magnesium ion (Mg). These ions aren't biologically significant and could only be an artefact. When crystallizing proteins they often form complexes (dimer, tetramers etc) but that doesn't mean that the functional structure is the same. They could be functional monomers. Those chains exist as individual functional units.

Image from PDB ProteinWorkshop 1.5

Figure:Chain A of arylformamidase


The red molecule in the middle is an unknown ligand containing a ring composed of 9 oxygen molecules. The green sphere is a chloride ion.

Image from PDB ProteinWorkshop 1.5

The protein backbone is coloured by conformation type:

Turn - blue

Coil- pink

Helix- green

strand- purple

Interaction of human arylformamidase (AFMID) with other proteins

Confidence interaction with names.png

The interaction between the proteins have been determined from curated STRING database (significant score). However there is no significant evidence for:

1- Neighborhood in the genome

2- Gene fusions

3- Cooccurence across genomes

4- Co-Expression

5- Experimental/Biochemical data

Interaction of Silicibacter Sp. arylformamidase (AFMID) with other proteins


TM1040_2226 Tryptophan 2,3-dioxygenase (279 aa)

TM1040_2225 Kynureninase (396 aa)

TM1040_2493 Succinic semialdehyde dehydrogenase (490 aa)

TM1040_1862 Hypothetical protein (212 aa)

TM1040_2491 Creatinase (402 aa)

TM1040_2736 Transketolase, putative (794 aa)

There is no significant evidence for these interactions (score= ~0.5)


The DALI tool produces proteins that are structurally similar to the protein of interest.

The search result showed similarities to mostly carboxylesterases/hydrolases. Hence there is strong evidence that our protein might also be a carboxylesterase.


Figure: Metagenomic Archea Carboxylesterase (Chain A ONLY)

ChainA 2c7b.PNG


PDB link title

Note: Chain B not shown

From PDB ProteinWorkshop 1.5

Figure: Archaeoglobus fulgidus Carboxylesterase (Chain A ONLY)

ChainA 1jji.PNG

File:Carboxylesterase (archaeon).txt

PDB link title

Note: Chains B, C & D not shown

From PDB ProteinWorkshop 1.5

Both of the above Archaeal carboxylesterases' chains exist as monomers (from literature). Hence it is expected that our protein exists as a monomer but during crystalization it interacts with its chains.

Secondary structure analysis

PDBSum output for arylformamidase



Figure: Archeon Carboxylesterase secondary structure

PDBsums.png From PDBsum

The conservation of the ser/his/asp catalytic triad

Catalytic triad conversation.PNG

Yellow indicates conservation

Blue indicates semi-conservation

Figure: The catalytic triad


The above image shows the conserved residues of the catalytic triad in arylformamidase, with the unknown ligand (Blue) protruding from a surface groove. The residues are serine 136, Histidine 241 and Glutamate 214. Note: The actual residue numbers are n+1

Image generated using Pymol

Figure: The conserved residues of arylformamidase

Cat triad red.PNG

The blue region shows the residues conserved among species. It is mostly around the unknown ligand. The conserved residues were obtained from observing the clustal alignment.

Image generated using Pymol

Figure: The catalytic triad


The above image shows the distance between the catalytic triad conserved residues and how each amino acid is linked to a turn region.

From PDB ProteinWorkshop 1.5

Figure: The conserved catalytic triad in Metagenomic Archea Carboxylesterase (PDB ID 2C7B)

Cattriad 2c7b.PNG

Figure: The conserved catalytic triad in Metagenomic Archea Carboxylesterase (PDB ID 1JJI)

Return to the main page...