Carbonyl sulfide hydrolase

Carbonyl sulfide hydrolase (EC 3.13.1.7; abbreviated as COSase) is an enzyme that degrades carbonyl sulfide (COS) to hydrogen sulfide (H2S) and carbon dioxide (CO2). Isolated from Thiobacillus thioparus bacterium, the potential of COSase would reduce the high global warming effect of COS and change the ozone chemistry, because COS is the source of sulfur in the troposphere.[1][2][3]

Carbonyl sulfide hydrolase (COSase)
Identifiers
EC no.3.13.1.7
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO
Search
PMCarticles
PubMedarticles
NCBIproteins
Carbonyl Sulfide Hydrolase (COSase)
Identifiers
SymbolCarbonyl Sulfide Hydrolase (COSase)
PfamPF00484
InterProIPR036874 IPR001765, IPR036874
SMARTSM00947
Available protein structures:
Pfam  structures / ECOD  
PDBRCSB PDB; PDBe; PDBj
PDBsumstructure summary

Etymology edit

Being that it is a hydrolase, which is an enzyme that uses water to break chemical bonds, the name suggests that within the mechanism are water molecules that are involved in disseminating molecules within the reaction. The very name when broken down means that it is an enzyme that breaks down carbonyl sulfide.

History edit

COSase was isolated, characterized and structure was determined from Thiobacillus thioparus bacterium. In search for a chemical method to break down COS more efficiently than the biologically established methods that employ the soil environment for degradation enzymes. These enzymes are carbonic anhydrase, carbonic disulfide hydrolase, nitrogenase, carbon monoxide, and RuBisCO.[4][5][6][7][8][9][10][11][12] The enzymes listed are limited in their use due to specificities and optimal environments, which is why chemical development of an enzyme unique to catalyzing the degradation of COS is researched. - Thiobacillus thioparus is a bacterium found both in soil and freshwater and is known for its sulfur-oxidizing properties. The strain used to create COSase is THI11, which was originally isolated as a thiocyanate degrading microorganism.[13] The enzyme was found by putting the extract of T. thioparus strain THI115 through column chromatography to purify it and ICP-MS to deduce the structure.[1]

Structure edit

Using sodium dodecyl sulfate–polyacrylamide gel electrophoresis, a subunit molecular mass of 27 kDa was found.[1] After testing for expression in E. coli the true molecular mass of ~94 kDa was found by SEC-MALS.[1] ICP-MS shows that there is one zinc ion per sub unit.[1] 35 amino acid sequence found on the N-terminal: MEKSNTDALLENNRLYAGGQATHRPGHPGMQPIQP.[1] There are five strands (β1−β5) that make up β-sheet core and four α-helices (α1, α2, α3, and α6) in its flank, with two additional helices (α4 and α5) that protrude from its core. They arrange in homodimer pairs to form ten-stranded β-sheets.[1] Between two subunits of a homodimer is the catalytic site. Cys44, His97, Cys 100, and a water molecule coordinate with a zinc ion, with a thiocyanate molecule in the catalytic site pocket.[1]

Function edit

COSase is responsible for the degradation of COS to H2S and CO2 in the second step of SCN assimilation. It hydrolyzes COS with a certain specificity over a wide range of concentrations both in vivo and in vitro.[1]

Mechanism edit

Thiocyanate hydrolase (SCNase) found in THI115 initiates enzymatic formation of thiocyanate (SCN). SCNase hydrolyzes SCN to ammonia and COS. The COS that results from the hydrolysis is metabolized to form hydrogen sulfide (H2S) which is oxidized to sulfate to produce energy.[14][15][16][17][18]

Hydroxide and zinc io ns perform a nucleophilic attack on the carbon in the COS molecule, which creates an intermediate with zinc bound to hydroxide oxygen and sulfur of the COS molecule. Oxygen is then released from zinc and forms CO2. Water from the solvent interacts with the su lfur-zinc ion and regenerates the active site and releases H2S.[1]

Carbonyl sulfide hydrolase inhibitor edit

COSase is weakly inhibited by SCN.[1]

References edit

  1. ^ a b c d e f g h i j k Ogawa T, Noguchi K, Saito M, Nagahata Y, Kato H, Ohtaki A, et al. (March 2013). "Carbonyl sulfide hydrolase from Thiobacillus thioparus strain THI115 is one of the β-carbonic anhydrase family enzymes". Journal of the American Chemical Society. 135 (10): 3818–25. doi:10.1021/ja307735e. PMID 23406161.
  2. ^ Chin M, Davis DD (1995). "A reanalysis of carbonyl sulfide as a source of stratospheric background sulfur aerosol". Journal of Geophysical Research. 100 (D5): 8993. Bibcode:1995JGR...100.8993C. doi:10.1029/95JD00275.
  3. ^ Andreae MO (16 May 1997). "Atmospheric Aerosols: Biogeochemical Sources and Role in Atmospheric Chemistry". Science. 276 (5315): 1052–1058. doi:10.1126/science.276.5315.1052.
  4. ^ Supuran CT (February 2008). "Carbonic anhydrases: novel therapeutic applications for inhibitors and activators". Nature Reviews. Drug Discovery. 7 (2): 168–81. doi:10.1038/nrd2467. PMID 18167490. S2CID 3833178.
  5. ^ Seefeldt LC, Rasche ME, Ensign SA (April 1995). "Carbonyl sulfide and carbon dioxide as new substrates, and carbon disulfide as a new inhibitor, of nitrogenase". Biochemistry. 34 (16): 5382–9. doi:10.1021/bi00016a009. PMID 7727396.
  6. ^ Protoschill-Krebs G, Wilhelm C, Kesselmeier J (September 1996). "Consumption of carbonyl sulphide (COS) by higher plant carbonic anhydrase (CA)". Atmospheric Environment. 30 (18): 3151–3156. Bibcode:1996AtmEn..30.3151P. doi:10.1016/1352-2310(96)00026-X.
  7. ^ Miller AG, Espie GS, Canvin DT (July 1989). "Use of Carbon Oxysulfide, a Structural Analog of CO(2), to Study Active CO(2) Transport in the Cyanobacterium Synechococcus UTEX 625". Plant Physiology. 90 (3): 1221–31. doi:10.1104/pp.90.3.1221. PMC 1061868. PMID 16666875.
  8. ^ Lorimer GH, Pierce J (February 1989). "Carbonyl sulfide: an alternate substrate for but not an activator of ribulose-1,5-bisphosphate carboxylase". The Journal of Biological Chemistry. 264 (5): 2764–72. doi:10.1016/S0021-9258(19)81679-4. PMID 2492523.
  9. ^ Haritos VS, Dojchinov G (January 2005). "Carbonic anhydrase metabolism is a key factor in the toxicity of CO2 and COS but not CS2 toward the flour beetle Tribolium castaneum [Coleoptera: Tenebrionidae]". Comparative Biochemistry and Physiology. Toxicology & Pharmacology. 140 (1): 139–47. doi:10.1016/j.cca.2005.01.012. PMID 15792633.
  10. ^ Ensign SA (April 1995). "Reactivity of carbon monoxide dehydrogenase from Rhodospirillum rubrum with carbon dioxide, carbonyl sulfide, and carbon disulfide". Biochemistry. 34 (16): 5372–8. doi:10.1021/bi00016a008. PMID 7727395.
  11. ^ Chengelis CP, Neal RA (October 1979). "Hepatic carbonyl sulfide metabolism". Biochemical and Biophysical Research Communications. 90 (3): 993–9. doi:10.1016/0006-291X(79)91925-9. PMID 116662.
  12. ^ Alterio V, Di Fiore A, D'Ambrosio K, Supuran CT, De Simone G (August 2012). "Multiple binding modes of inhibitors to carbonic anhydrases: how to design specific drugs targeting 15 different isoforms?". Chemical Reviews. 112 (8): 4421–68. doi:10.1021/cr200176r. hdl:2158/776392. PMID 22607219.
  13. ^ Katayama Y, Narahara Y, Inoue Y, Amano F, Kanagawa T, Kuraishi H (May 1992). "A thiocyanate hydrolase of Thiobacillus thioparus. A novel enzyme catalyzing the formation of carbonyl sulfide from thiocyanate". The Journal of Biological Chemistry. 267 (13): 9170–5. doi:10.1016/S0021-9258(19)50404-5. PMID 1577754.
  14. ^ Sauze J, Ogée J, Maron PA, Crouzet O, Nowak V, Wohl S, et al. (December 2017). "18O and OCS exchange". Soil Biology & Biochemistry. 115: 371–382. doi:10.1016/j.soilbio.2017.09.009. PMC 5666291. PMID 29200510.
  15. ^ Berben T, Balkema C, Sorokin DY, Muyzer G (26 December 2017). "T Using Transcriptomics". mSystems. 2 (6): mSystems.00102–17, e00102–17. doi:10.1128/mSystems.00102-17. PMC 5744179. PMID 29285524.
  16. ^ Sun W, Kooijmans LM, Maseyk K, Chen H, Mammarella I, Vesala T, Levula J, Keskinen H, Seibt U (1 February 2018). "Soil fluxes of carbonyl sulfide (COS), carbon monoxide, and carbon dioxide in a boreal forest in southern Finland". Atmospheric Chemistry and Physics. 18 (2): 1363–1378. Bibcode:2018ACP....18.1363S. doi:10.5194/acp-18-1363-2018.
  17. ^ Sun W, Maseyk K, Lett C, Seibt U (4 June 2018). "Stomatal control of leaf fluxes of carbonyl sulfide and CO<sub>2</sub> in a <i>Typha</i> freshwater marsh". Biogeosciences. 15 (11): 3277–3291. Bibcode:2018BGeo...15.3277S. doi:10.5194/bg-15-3277-2018.
  18. ^ Zhao S, Yi H, Tang X, Kang D, Yu Q, Gao F, Wang J, Huang Y, Yang Z (1 February 2018). "Mechanism of activity enhancement of the Ni based hydrotalcite-derived materials in carbonyl sulfide removal". Materials Chemistry and Physics. 205: 35–43. doi:10.1016/j.matchemphys.2017.11.002.

Further reading edit