Disease relevance of cysH

• Characterization of the cysJIH regions of Salmonella typhimurium and Escherichia coli B. DNA sequences of cysI and cysH and a model for the siroheme-Fe4S4 active center of sulfite reductase hemoprotein based on amino acid homology with spinach nitrite reductase [1].
• Characterisation of the gene cysH and of its product phospho-adenylylsulphate reductase from Escherichia coli [2].
• A gene cluster containing homologues of the genes cysB, cysJI and cysH was found in the genome of the sulphur-oxidizing purple bacterium Thiocapsa roseopersicina [3].
• Random Tn917 mutagenesis of Bacillus subtilis followed by selection of lipoic acid auxotrophs led to the isolation of the cysH gene [4].

High impact information on cysH

• The ts mutation was mapped to 60.6 min of the S. typhimurium chromosome and was linked to argA and cysH [5].
• Molecular weights deduced for the cysI-encoded sulfite reductase hemoprotein and for the cysH-encoded 3'-phosphoadenosine 5'-phosphosulfate sulfotransferase were approximately 64,000 and 28,000, respectively [1].
• In order to determine the specificity of the R. meliloti reductase, the R. meliloti cysH homolog was histidine tagged and purified, and its specificity was assayed in vitro [6].
• Expression of lacZ fused to the cysH promoter was repressed by cysteine and sulfide and induced by sulfur limitation, indicating that cysH is controlled at the level of transcription [4].
• Both thioredoxin and glutaredoxin have been shown to be hydrogen donors for PAPS reductase (cysH) in vitro (M. L.-S. Tsang, J. Bacteriol. 146:1059-1066, 1981), and one or the other of these compounds is presumably essential in vivo for growth on minimal medium containing sulfate as the sulfur source [7].

Chemical compound and disease context of cysH

• Involvement of the only Cys and of Tyr209 in the reduction of PAdoPS to sulfite was investigated by site-specific mutagenesis: cysH was mutated by single-strand-overlay extension PCR; the mutated genes were cloned in pBTac1 and expressed in E. coli RL 22 (delta cysHIJ) [8].

Biological context of cysH

• The open reading frame was 735 nucleotides in length; it was flanked by a repetitive palindromic sequence centred 36 nucleotides upstream of cysH and a terminator-like structure located 20 nucleotides downstream [2].

Associations of cysH with chemical compounds

• The structural gene (cysH) encodes for a small polypeptide with a single Cys residue located in a conserved cluster (KXECGI/LH) of amino acids [8].

References