3bsqA Results

MSA highlited sevlral residues in N-terminal region of the molecule which are highly conserved (figure 1).

The three dimentional structure of the enzyme was viewed using PyMol (figure 2) and these conserved residues were marked on the crystal structure. However they were not related to binding sited of Cl and Zn, but buried in the core of the protein within a pocket-like region (figure 3). All attempts to see the electrostatic nature of this pocket were unsuccessful, due to some technical probloems with PyMol.

Three dimentional structure of arylsulfatase was aligned with other available structures using DALI server (structural alignment). Results are shown in 'figure 4'.

 No:  Chain   Z    rmsd lali nres  %id   Description
  1:  3b5q-A 73.6  0.0  464   464  100   MOLECULE: PUTATIVE SULFATASE YIDJ;                                   
  2:  3b5q-B 70.2  0.3  464   467  100   MOLECULE: PUTATIVE SULFATASE YIDJ;                                   
  3:  2qzu-A 35.1  2.5  375   465   25   MOLECULE: PUTATIVE SULFATASE YIDJ;                                   
  4:  1fsu   28.7  2.8  344   474   22   MOLECULE: N-ACETYLGALACTOSAMINE-4-SULFATASE;                         
  5:  1n2l-A 28.4  3.0  343   483   25   MOLECULE: ARYLSULFATASE A;                                           
  6:  1n2k-A 28.3  3.2  344   482   25   MOLECULE: ARYLSULFATASE A;                                           
  7:  1e3c-P 28.2  3.2  344   481   26   MOLECULE: ARYLSULFATASE A;                                           
  8:  1e33-P 28.2  3.1  344   480   25   MOLECULE: ARYLSULFATASE A;                                           
  9:  1e2s-P 28.2  3.1  343   481   25   MOLECULE: ARYLSULFATASE A;                                           
 10:  1e1z-P 28.1  3.2  344   481   26   MOLECULE: ARYLSULFATASE A;                                           
 11:  1auk   27.9  3.1  343   481   25   MOLECULE: ARYLSULFATASE A;  

Figure 4: Structurally related proteins. (No 1 and 2 are two chains of arylsulfatase K).

The function of highly related proteins were found using ProFunc. Putative Sulfatase YIDI hydrolyses sulfuric ester bonds of its substrate hence significant in metabolism. Arylsulfatase A has both sulfuric ester hydrolase and phosphoric monoester hydrolase activities.

Protein interactions of arylsulfatase K with other proteis were viewed usig the programme STRING, which revealed four major hits depending on 'neighbourhood', 'cooccurreance' and 'homology' evidence. 'Putative secreted sulfatase ydeN' only showed neignbourhood relationship, which means that their genes are located in close proximity. But three of other proteins showed both cooccurrence and homology evidence, therefore their functions were analysed with ProFunc.

N-acetylgalactosamine-6-sulfatase cleaves the 6-sulfate groups of N-acetyl-D-galactosamine 6-sulfate units in chondroitin sulfate and D-galactose 6-sulfate units in keratan sulfate. N-sulphoglucosamine sulphohydrolase is also known as heparine sulfamidase, which catalyses the hydrolysis of Sulfur-Nitrogen bonds. N-sulphoglucosamine sulphohydrolase is responsible for the degradation of glucosaminlglycan and glycan structure of extra cellular matrix.

N-sulfo-D-glucosamine + H(2)O <=> D-glucosamine + sulfate