KEGG   ENZYME: 4.2.1.115Help
Entry
EC 4.2.1.115                Enzyme                                 

Name
UDP-N-acetylglucosamine 4,6-dehydratase (configuration-inverting);
FlaA1;
UDP-N-acetylglucosamine 5-inverting 4,6-dehydratase;
PseB;
UDP-N-acetylglucosamine hydro-lyase (inverting;
UDP-2-acetamido-2,6-dideoxy-beta-L-arabino-hex-4-ulose-forming)
Class
Lyases;
Carbon-oxygen lyases;
Hydro-lyases
BRITE hierarchy
Sysname
UDP-N-acetyl-alpha-D-glucosamine hydro-lyase (inverting; UDP-2-acetamido-2,6-dideoxy-beta-L-arabino-hex-4-ulose-forming)
Reaction(IUBMB)
UDP-N-acetyl-alpha-D-glucosamine = UDP-2-acetamido-2,6-dideoxy-beta-L-arabino-hex-4-ulose + H2O [RN:R09697]
Reaction(KEGG)
Substrate
UDP-N-acetyl-alpha-D-glucosamine [CPD:C00043]
Product
UDP-2-acetamido-2,6-dideoxy-beta-L-arabino-hex-4-ulose [CPD:C19823];
H2O [CPD:C00001]
Comment
Contains NADP+ as a cofactor. This is the first enzyme in the biosynthetic pathway of pseudaminic acid [3], a sialic-acid-like sugar that is unique to bacteria and is used by Helicobacter pylori to modify its flagellin. This enzyme plays a critical role in H. pylori's pathogenesis, being involved in the synthesis of both functional flagella and lipopolysaccharides [1,2]. It is completely inhibited by UDP-alpha-D-galactose. The reaction results in the chirality of the C-5 atom being inverted. It is thought that Lys-133 acts sequentially as a catalytic acid, protonating the C-6 hydroxy group and as a catalytic base, abstracting the C-5 proton, resulting in the elimination of water. This enzyme belongs to the short-chain dehydrogenase/reductase family of enzymes.
History
EC 4.2.1.115 created 2009
Pathway
Amino sugar and nucleotide sugar metabolism
Orthology
K15894  
UDP-N-acetylglucosamine 4,6-dehydratase
Genes
PPW: 
PPRC: 
PFO: 
PFE: 
PSV: 
SON: 
SO_3271(pseB)
SDN: 
SBL: 
SBP: 
SBS: 
SBB: 
SLO: 
SPC: 
SHN: 
SHW: 
SHL: 
PAT: 
PSM: 
AMC: 
AMAC: 
AMB: 
AMG: 
AMK: 
AMAA: 
AMAL: 
AMAE: 
AMAO: 
AMAD: 
AMAI: 
AMAG: 
ALT: 
GAG: 
GNI: 
GPS: 
LPM: 
LP6_0759(capD1)
LPE: 
FNA: 
FNL: 
MMW: 
MPC: 
AHA: 
AHY: 
ASA: 
RPF: 
BPH: 
HPY: 
HEO: 
HPJ: 
HPA: 
HPS: 
HHP: 
HHQ: 
HHR: 
HPG: 
HPP: 
HPB: 
HELPY_0515(flaA1)
HPL: 
HPC: 
HCA: 
HPM: 
HPE: 
HPO: 
HPI: 
HPQ: 
HPW: 
HPU: 
HEF: 
HPF: 
HEQ: 
HEX: 
HPT: 
HPZ: 
HPV: 
HPX: 
HEN: 
HPH: 
HEG: 
HPN: 
HEP: 
HEU: 
HES: 
HPYS: 
HCN: 
HPD: 
KHP_0488(flaA1)
HER: 
HEI: 
HPYA: 
HPYK: 
HPYO: 
HPYL: 
HPYR: 
HPYI: 
HPYU: 
HPYM: 
HEM: 
HEB: 
HEZ: 
HHE: 
HH1333(flmA)
HAC: 
Hac_1210(flaA1)
HMS: 
HMU09920(flaA1)
HFE: 
HBI: 
HCE: 
HCM: 
HCP: 
HCN_1966(flmA)
HCB: 
HHM: 
WSU: 
SUA: 
SKU: 
SULR: 
CJE: 
Cj1293(pseB)
CJB: 
CJJ: 
CJU: 
CJN: 
CJI: 
CJSA_1231(pseB)
CJM: 
CJM1_1275(flmA)
CJS: 
CJS3_1390(pseB)
CJP: 
CJEJ: 
CJEU: 
CJEN: 
CJEI: 
CJR: 
CJE1485(flmA)
CJD: 
CJZ: 
CJX: 
CFF: 
CFV: 
CCV: 
CLA: 
Cla_1298(pseB)
CCOL: 
CCC: 
CCQ: 
CAMP: 
ABU: 
Abu_2243(pseB)
ABT: 
ABL: 
ANT: 
SDL: 
SBA: 
NAM: 
DHY: 
DRT: 
DSF: 
DAT: 
HMR: 
BJU: 
NWI: 
NHA: 
CCR: 
CCS: 
CAK: 
CSE: 
PZU: 
PHZ_c0080(flmA)
AEX: 
PDE: 
MMR: 
HBA: 
MAG: 
MGY: 
AZL: 
ALI: 
ABS: 
MGM: 
PEL: 
APM: 
GMC: 
DRU: 
SSG: 
SRI: 
AMS: 
ACTN: 
AFS: 
PCU: 
PUV: 
PUV_20480(capD)
WCH: 
wcw_1563(flaA1)
TAI: 
NPU: 
CALO: 
PSEU: 
HTE: 
DIN: 
DAP: 
NMR: 
 » show all
Taxonomy
Reference
1  [PMID:16651261]
  Authors
Ishiyama N, Creuzenet C, Miller WL, Demendi M, Anderson EM, Harauz G, Lam JS, Berghuis AM
  Title
Structural studies of FlaA1 from Helicobacter pylori reveal the mechanism for inverting 4,6-dehydratase activity.
  Journal
J. Biol. Chem. 281 (2006) 24489-95.
  Organism
Helicobacter pylori [GN:hpy]
  Sequence
[hpy:HP0840]
Reference
2  [PMID:12791140]
  Authors
Schirm M, Soo EC, Aubry AJ, Austin J, Thibault P, Logan SM
  Title
Structural, genetic and functional characterization of the flagellin glycosylation process in Helicobacter pylori.
  Journal
Mol. Microbiol. 48 (2003) 1579-92.
  Organism
Helicobacter pylori [GN:hpy]
  Sequence
[hpy:HP0840]
Reference
3  [PMID:16751642]
  Authors
Schoenhofen IC, McNally DJ, Brisson JR, Logan SM
  Title
Elucidation of the CMP-pseudaminic acid pathway in Helicobacter pylori: synthesis from UDP-N-acetylglucosamine by a single enzymatic reaction.
  Journal
Glycobiology. 16 (2006) 8C-14C.
  Organism
Helicobacter pylori [GN:hpy]
  Sequence
[hpy:HP0840]
Other DBs
ExplorEnz - The Enzyme Database: 
IUBMB Enzyme Nomenclature: 
ExPASy - ENZYME nomenclature database: 
BRENDA, the Enzyme Database: 

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