Disease relevance of sufS

• sufS was found to suppress the only known suppressible-1 frameshift mutation, trpE91, at a site identified as GGA and mapped within the single gene of the only tRNA that can decode GGA in Escherichia coli [1].
• It mapped to the same gene in Salmonella typhimurium. sufS alleles were recessive, and dominant alleles could not be isolated [1].
• Selenocysteine lyase (EC 4.4.1.16) exclusively decomposes selenocysteine to alanine and elemental selenium, whereas cysteine desulfurase (NIFS protein) of Azotobacter vinelandii acts indiscriminately on both cysteine and selenocysteine to produce elemental sulfur and selenium respectively, and alanine [2].

High impact information on sufS

• Although the enzyme was not specific for L-selenocysteine, the high specific activity for L-selenocysteine (5.5 units/mg compared with 0.019 units/mg for L-cysteine) supports the view that the enzyme can be regarded as an E. coli counterpart of mammalian selenocysteine lyase [3].
• An open reading frame, named csdB, from Escherichia coli encodes a putative protein that is similar to selenocysteine lyase of pig liver and cysteine desulfurase (NifS) of Azotobacter vinelandii [3].
• Selenocysteine lyase is a pyridoxal 5'-phosphate (PLP)-dependent enzyme that catalyzes the exclusive decomposition of L-selenocysteine to L-alanine and elemental selenium [3].
• External suppressors, sufS, of a -1 frameshift mutant cause ribosomes to shift into the -1 frame when reading the sequence CAG GGA GUG [4].
• After overcoming terminological complications to sort out microbial nifS from sufS genes, we connect a bacterial operon, recently found to be involved in iron metabolism, the formation of [Fe-S] clusters and oxidative stress to a potentially important gene (sufB) carried on the degenerate plastid genome of malaria and related parasites [5].

Chemical compound and disease context of sufS

• Cysteine sulfinate desulfinase, a NIFS-like protein of Escherichia coli with selenocysteine lyase and cysteine desulfurase activities. Gene cloning, purification, and characterization of a novel pyridoxal enzyme [2].

Biological context of sufS

• Sequence analysis revealed that the sufS open reading frame corresponds to orf f406 [6].

Associations of sufS with chemical compounds

• Selenocysteine lyase enzymes, which decompose selenocysteine to elemental selenium (Se(0)) and alanine, were considered as candidates for the control of free selenium levels in vivo [7].

References