ribR [Tue Dec 13 2016 11:16:35 GMT+0100 (CET)]

riboflavin kinase with preference for dihydroriboflavin, binds FMN riboswitches of the rib operon and of ribU to allow expression even in the presence of FMN, required for the conversion of S-methyl-cysteine to cysteine

locus: BSU29300

pI: 9.00

mw: 26.00 kDa

function: utilization of S-methyl-cysteine, regulation of rib operon expression

product: riboflavin kinase with preference for dihydroriboflavin

essential: no

synonyms: ytnK

Genomic Context

categories

• [category|SW 2|Metabolism] → [category|SW 2.6|Additional metabolic pathways] → [category|SW 2.6.4|Sulfur metabolism] → [category|SW 2.6.4.1|Conversion of S-methyl cysteine to cysteine]
• [category|SW 6|Groups of genes] → [category|SW 6.6|Poorly characterized/ putative enzymes]

[SW|Categories] containing this gene/protein

• [SW|biosynthesis of cofactors], [SW|sulfur metabolism], [SW|RNA binding regulators]

This gene is a member of the following [SW|regulons]

• [SW|CymR regulon], [SW|AscR regulon]

Gene

Coordinates on the chromosome (coding sequence): 3,000,985 -> 3,001,677

Phenotypes of a mutant

• no growth with S-methyl cysteine [Pubmed|23944997]

The protein

Catalyzed reaction/ biological activity

• synthesis of FMNH₂ [Pubmed|26494285]
• binds the [SW|FMN riboswitch] [Pubmed|26494285]
• prevents transcription termination of the ''[protein|search|ribD]-[protein|search|ribE]-[protein|search|ribA]-[protein|search|ribH]-[protein|search|ribT]'' operon even in the presence of FMN or FMNH₂ [Pubmed|26494285]
• prevents sequestration of the ribosome binding site of the ''[protein|search|ribU]'' mRNA even in the presence of FMN or FMNH₂ [Pubmed|26494285]

Expression and Regulation

Operon

• ''[protein|search|snaA]-[protein|search|tcyJ]-[protein|search|tcyK]-[protein|search|tcyL]-[protein|search|tcyM]-[protein|search|tcyN]-[protein|search|cmoO]-[protein|search|cmoI]-[protein|search|cmoJ]-[protein|search|ribR]-[protein|search|sndA]-[protein|search|ytnM]'' [Pubmed|15668000]

[SW|Sigma factor]

• [protein|search|SigA] [Pubmed|15272571]

Regulation

• repressed in the presence of cysteine ([protein|search|CymR]) [Pubmed|16109943]
• induced in the presence of S-methyl-cysteine ([protein|search|AscR]) [Pubmed|23944997]
• induced in the presence of methionine and taurine [Pubmed|11390694]

Regulatory mechanism

• [protein|search|CymR]: transcription repression [Pubmed|16109943]
• [protein|search|AscR]: transcription activation [Pubmed|16109943]

References

• 17590224,15668000,16109943,15272571,23944997,11390694,26494285