Entry
Name
aerobic 5,6-dimethylbenzimidazole synthase;
BluB;
flavin destructase
Class
Oxidoreductases;
Acting on single donors with incorporation of molecular oxygen (oxygenases);
With incorporation of two atoms of oxygen
BRITE hierarchy
Sysname
FMNH2 oxidoreductase (5,6-dimethylbenzimidazole-forming)
Reaction(IUBMB)
FMNH2 + O2 = 5,6-dimethylbenzimidazole + D-erythrose 4-phosphate + other product(s) [RN:
R09083 ]
Reaction(KEGG)
Substrate
Product
5,6-dimethylbenzimidazole [CPD:
C03114 ];
D-erythrose 4-phosphate [CPD:
C00279 ];
other product(s)
Comment
The enzyme catalyses a complex oxygen-dependent conversion of reduced flavin mononucleotide to form 5,6-dimethylbenzimidazole, the lower ligand of vitamin B12. This conversion involves many sequential steps in two distinct stages, and an alloxan intermediate that acts as a proton donor, a proton acceptor, and a hydride acceptor [4]. The C-2 of 5,6-dimethylbenzimidazole is derived from C-1' of the ribityl group of FMNH2 and 2-H from the ribityl 1'-pro-S hydrogen. While D-erythrose 4-phosphate has been shown to be one of the byproducts, the nature of the other product(s) has not been verified yet.
History
EC 1.13.11.79 created 2010 as EC 1.14.99.40, transferred 2014 to EC 1.13.11.79, modified 2019
Pathway
Orthology
K04719 5,6-dimethylbenzimidazole synthase
Genes
PPUD : DW66_1247 DW66_1609
PMUD : NCTC8068_03847(bluB)
PFW : PF1751_v1c39830(bluB)
PPUU : PputUW4_03773(bluB)
PTRT : HU722_0021110(bluB)
MSHE : MAALD49_02380 MAALD49_05020
BPL : BURPS1106A_3208(bluB)
PDIO : PDMSB3_1431.1(bluB)
PLG : NCTC10937_04026(drgA)
LMIR : NCTC12852_01583(nox)
ACID : CBP33_07740 CBP33_18820
ACIP : CBP36_08310 CBP36_19120
ACIS : CBP35_10620 CBP35_19070
MPT : Mpe_B0452(cysG) Mpe_B0487(cysG)
SMEL : SM2011_c00166(bluB)
SFD : USDA257_c41170(bluB)
SAME : SAMCFNEI73_Ch2071(bluB)
ALF : CFBP5473_08565(bluB)
AVV : RvVAT039_31310(bluB)
AVF : RvVAR031_18280(bluB)
ASAL : CFBP5507_06925(bluB)
RPUS : CFBP5875_06860(bluB)
ALEG : CFBP4996_06620(bluB)
REL : REMIM1_CH02380(bluB)
REP : IE4803_CH02402(bluB)
REI : IE4771_CH02490(bluB)
RTR : RTCIAT899_CH12935(bluB)
RGA : RGR602_CH02141(bluB)
RPHA : AMC79_CH02487(bluB)
RLW : RlegWSM1455_11145(bluB)
RBW : RLCC275e_11320(bluB)
NEN : NCHU2750_17230(bluB)
BRK : CWS35_19560(bluB) CWS35_24770
BSEP : HAP48_0032315(bluB)
BCAN : BcanWSM471_15495(bluB)
MAQU : Maq22A_c24535(nfnB)
MMES : MMSR116_26340(bluB)
MLD : U0023_25625(bluB) U0023_28880(bluB)
FIL : BN1229_v1_1057(bluB)
FIY : BN1229_v1_1059(bluB)
RLI : RLO149_c006290(bluB)
OAT : OAN307_c11000(bluB1) OAN307_c37400(bluB2)
AHT : ANTHELSMS3_03563(bluB)
LVS : LOKVESSMR4R_00075(bluB)
GEH : HYN69_19310(bluB) HYN69_20120(bluB)
ACRO : K3J57_02030(bluB) K3J57_03155(bluB)
ALK : ALEK_0092 ALEK_0331(bluB)
BAYD : BSPP4475_14955(bluB)
PCHI : PC41400_07790(bluB)
MHEK : JMUB5695_04412(bluB)
MPHL : MPHLCCUG_00478(bluB)
MTHN : 4412656_04105(drgA_2)
MGO : AFA91_10500 AFA91_20110
MSAL : DSM43276_03140(bluB_1)
MTER : 4434518_00283(drgA)
NFR : ERS450000_05323(nox_2)
RANT : RHODO2019_10650(bluB)
PPC : HMPREF9154_2365(bluB)
NAQU : ENKNEFLB_00275(bluB_1)
ARHD : VSH64_19285 VSH64_24635(bluB)
KUT : JJ691_53270 JJ691_71080
NDE : NIDE2104(bluB) NIDE2667
NMV : NITMOv2_1603 NITMOv2_1834
HJT : DVR14_17650(bluB) DVR14_21780(bluB)
» show all
Taxonomy
Reference
Authors
Gray MJ, Escalante-Semerena JC
Title
Single-enzyme conversion of FMNH2 to 5,6-dimethylbenzimidazole, the lower ligand of B12.
Journal
Sequence
Reference
Authors
Ealick SE, Begley TP
Title
Biochemistry: molecular cannibalism.
Journal
Reference
Authors
Taga ME, Larsen NA, Howard-Jones AR, Walsh CT, Walker GC
Title
BluB cannibalizes flavin to form the lower ligand of vitamin B12.
Journal
Sequence
Reference
Authors
Wang XL, Quan JM
Title
Intermediate-assisted multifunctional catalysis in the conversion of flavin to 5,6-dimethylbenzimidazole by BluB: a density functional theory study.
Journal
Reference
Authors
Collins HF, Biedendieck R, Leech HK, Gray M, Escalante-Semerena JC, McLean KJ, Munro AW, Rigby SE, Warren MJ, Lawrence AD
Title
Bacillus megaterium has both a functional BluB protein required for DMB synthesis and a related flavoprotein that forms a stable radical species.
Journal
Other DBs