ribH

riboflavin synthase (beta subunit)

locus: BSU_23250

pI: 5.20

mw: 16.14 kDa

protein length: 154 aa

gene length: 465 bp

function: riboflavin biosynthesis

product: riboflavin synthase (beta subunit)

essential: no

ec: 2.5.1.9

synonyms

Genomic Context

categories

• [category|SW 2|Metabolism] → [category|SW 2.6|Additional metabolic pathways] → [category|SW 2.6.2|Biosynthesis of cofactors] → [category|SW 2.6.2.2|Biosynthesis/ acquisition of riboflavin/ FAD]

Gene

Coordinates: 2,427,892 2,428,356

The protein

Catalyzed reaction/ biological activity

• (2S)-2-hydroxy-3-oxobutyl phosphate + 5-amino-6-(D-ribitylamino)uracil --> 6,7-dimethyl-8-(1-D-ribityl)lumazine + H⁺ + 2 H₂O + phosphate (according to UniProt)

Protein family

• DMRL synthase family (single member, according to UniProt)

Structure

• [PDB|1ZIS], [PDB|1RVV] (the [protein|4E18BD4B084094EE4FBC8FE2AC95B14581D20C0F|RibE])3-([protein|2A5DCBFAB51996F0DDEC964D5D178274AF86CE69|RibH])60 lumazine synthase/riboflavin synthase complex) [Pubmed|7473709]

Expression and Regulation

Operons

• genes: [gene|3DFCF7C5FE15C9A3E9E7E4B0DA8E926B85DBD180|ribD]-[gene|4E18BD4B084094EE4FBC8FE2AC95B14581D20C0F|ribE]-[gene|F07B7062C850106A95C15978E36DA500F8B089D6|ribA]-[gene|2A5DCBFAB51996F0DDEC964D5D178274AF86CE69|ribH]-[gene|8146A052E4E7844F781E7169C264EC927DEB7387|ribT]
  description: [Pubmed|8159171]

  sigma factors

  • [protein|360F48D576DE950DF79C1A2677B7A35A8D8CC30C|SigA]: sigma factor, [Pubmed|8159171], in [regulon|360F48D576DE950DF79C1A2677B7A35A8D8CC30C|SigA regulon]

  regulatory mechanism

  • [regulon|FMN-box|FMN-box]: transcription termination, via [SW|FMN-box] in the presence of FMN or FMNH₂, this is counter-acted upon binding of [protein|3D32B6C1DC9CAC615B02E14EA846648C3B0E61D6|RibR], in [regulon|FMN-box|FMN-box]

  regulation

  • expressed in the absence of FMN ([SW|FMN-box]) [Pubmed|15808508]
  • binding of FMN to the [SW|FMN-box] RNA is facilitated by [protein|43CFA3477B4EEB4CE0B2DF63ED2B5EDB171E79C7|NusG]-mediated transcription pausing [pubmed|32817529]
  • the [SW|FMN-box] RNA is degraded by [protein|872CCB5A49C9000BD95E4B0472556D5F60F7D7A4|RNase Y] [pubmed|29794222]

Biological materials

Mutant

• BKE23250 ([gene|2A5DCBFAB51996F0DDEC964D5D178274AF86CE69|ribH]::erm trpC2) available at [http://www.bgsc.org/getdetail.php?bgscid=BKE23250 BGSC], [Pubmed|28189581], upstream reverse: _UP1_CATATGATTCCCATCCTTTT, downstream forward: _UP4_TAATTTGCTGAAAACAGTTT
• BKK23250 ([gene|2A5DCBFAB51996F0DDEC964D5D178274AF86CE69|ribH]::kan trpC2) available at [http://www.bgsc.org/getdetail.php?bgscid=BKK23250 BGSC], [Pubmed|28189581], upstream reverse: _UP1_CATATGATTCCCATCCTTTT, downstream forward: _UP4_TAATTTGCTGAAAACAGTTT

References

Reviews

• 11395405

Original publications

• 12456892,15808508,7473709,8159171,7934830,3100522,23270261,24442413,26494285,29087189