title: The proteins of Fusobacterium spp. involved in hydrogen sulfide production from L-cysteine.
abstract: Hydrogen sulfide (H2S) is a toxic foul-smelling gas produced by subgingival biofilms in patients with periodontal disease and is suggested to be part of the pathogenesis of the disease. We studied the H2S-producing protein expression of bacterial strains associated with periodontal disease. Further, we examined the effect of a cysteine-rich growth environment on the synthesis of intracellular enzymes in F. nucleatum polymorphum ATCC 10953. The proteins were subjected to one-dimensional (1DE) and two-dimensional (2DE) gel electrophoresis An in-gel activity assay was used to detect the H2S-producing enzymes; Sulfide from H2S, produced by the enzymes in the gel, reacted with bismuth forming bismuth sulfide, illustrated as brown bands (1D) or spots (2D) in the gel. The discovered proteins were identified with liquid chromatography - tandem mass spectrometry (LC-MS/MS).
  
  
  
  Cysteine synthase and proteins involved in the production of the coenzyme pyridoxal 5'phosphate (that catalyzes the production of H2S) were frequently found among the discovered enzymes. Interestingly, a higher expression of H2S-producing enzymes was detected from bacteria incubated without cysteine prior to the experiment.
  
  
  
  Numerous enzymes, identified as cysteine synthase, were involved in the production of H2S from cysteine and the expression varied among Fusobacterium spp. and strains. No enzymes were detected with the in-gel activity assay among the other periodontitis-associated bacteria tested. The expression of the H2S-producing enzymes was dependent on environmental conditions such as cysteine concentration and pH but less dependent on the presence of serum and hemin.
authors.affiliation: Department of Oral Microbiology and Immunology, Institute of Odontology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. amina.basic@gu.se.
authors.forename: Amina
authors.initials: A
authors.lastname: Basic
authors.affiliation: Department of Oral Biology, Institute of Odontology, Malmö University, Malmö, Sweden.
authors.forename: Madeleine
authors.initials: M
authors.lastname: Blomqvist
authors.affiliation: Department of Oral Microbiology and Immunology, Institute of Odontology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Gunnar
authors.initials: G
authors.lastname: Dahlén
authors.affiliation: Department of Oral Biology, Institute of Odontology, Malmö University, Malmö, Sweden.
authors.forename: Gunnel
authors.initials: G
authors.lastname: Svensäter
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis / Q000378:metabolism*; D018441:Biofilms; D001729:Bismuth / Q000378:metabolism; D003545:Cysteine / Q000378:metabolism*; D003547:Cysteine Synthase / Q000378:metabolism; D003773:Dental Plaque; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D005673:Fusobacterium / Q000201:enzymology* / Q000378:metabolism*; D006801:Humans; D006862:Hydrogen Sulfide / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D010510:Periodontal Diseases / Q000382:microbiology; D040901:Proteomics; D013440:Sulfides / Q000378:metabolism; D053719:Tandem Mass Spectrometry
chemical_list: D001426:Bacterial Proteins; D013440:Sulfides; D003547:Cysteine Synthase; D003545:Cysteine; D001729:Bismuth; C049897:bismuth sulfide; D006862:Hydrogen Sulfide
keywords: 2D gel electrophoresis; Bismuth sulfide; Enzymes; Fusobacterium spp.; Hydrogen sulfide; LC-MS/MS; Periodontitis; Proteomics