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discounted EARLY registration ends Dec 31, 2014
BioCyc websites down
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discounted EARLY registration ends Dec 31, 2014
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MetaCyc Enzyme: poly-β-1,6-N-acetyl-D-glucosamine N-deacetylase

Gene: pgaB Accession Numbers: G6530 (MetaCyc), b1023, ECK1013

Synonyms: hmsF, ycdR

Species: Escherichia coli K-12 substr. MG1655

Summary:
The pgaABCD locus is required for the synthesis of a cell-bound hexosamine-rich polysaccharide, which was identified as a linear polymer of beta-1,6-N-acetylglucosamine residues (PGA), an adhesin essential in biofilm formation [Wang04, Itoh05]. PgaB is involved in the transport of PGA across the outer membrane and is involved in biofilm formation. The PgaB protein belongs to the carbohydrate esterase family 4 and contains putative polysaccharide N-deacetylase domains. N-deacetylation of PGA by PgaB promotes its transport across the outer membrane. PgaB is a predicted lipoprotein.

A pgaB mutant has reduced biofilm formation [Wang04]. pgaB mutants do not release significant amounts of PGA into the medium during shaking at 26 C compared to wild-type, though they are able to release some PGA at 37 C [Itoh08]. PGA from pgaB mutants is not externally exposed showing PgaB is involved in transport of PGA across the outer membrane [Itoh08]. Mutation of the deacetylase reaction site of PgaB prevents export of PGA and biofilm formation [Itoh08]. Analysis of free amino groups in PGA from pgaB+ strains and pgaB mutants reveals that PgaB is responsible for N-deacetylation of PGA [Itoh08].

Expression of pgaABCD is higher at 37 C than at 21 C and is highest during stationary phase [Cerca08]. Expression also increased in response to one-percent NaCl or ethanol [Cerca08]. Expression increased in response to glucose, ethanol, NaCl, and MnCl2 in a clinical isolate, and dramatically increased upon deletion or mutation of csrA in this strain [Cerca08, Mercante06]. CsrA inhibits translation of pgaABCD mRNA by binding to six sites within the pgaABCD leader [Wang05, Mercante06]. NaCl and alkaline pH induction are dependent upon nhaR as deletion of this gene prevented induction [Goller06, Cerca08].

PgaB has similarity to the HmsF protein encoded by the Yersinia pestis hmsHFRST gene cluster, which is involved in plague transmission [Jones99].

Citations: [Agladze05]

Locations: outer membrane

Map Position: [1,087,062 <- 1,089,080]

Molecular Weight of Polypeptide: 77.413 kD (from nucleotide sequence)

Unification Links: ASAP:ABE-0003467 , DIP:DIP-11513N , EchoBASE:EB3624 , EcoGene:EG13864 , EcoliWiki:b1023 , ModBase:P75906 , OU-Microarray:b1023 , PortEco:pgaB , Protein Model Portal:P75906 , RefSeq:NP_415542 , RegulonDB:G6530 , SMR:P75906 , String:511145.b1023 , UniProt:P75906

Relationship Links: InterPro:IN-FAMILY:IPR002509 , InterPro:IN-FAMILY:IPR011330 , InterPro:IN-FAMILY:IPR023854 , PDB:Structure:3VUS , PDB:Structure:4F9D , PDB:Structure:4F9J , Pfam:IN-FAMILY:PF01522 , Prosite:IN-FAMILY:PS51257 , Prosite:IN-FAMILY:PS51677

Gene-Reaction Schematic: ?

GO Terms:

Biological Process: GO:0042710 - biofilm formation Inferred from experiment Inferred by computational analysis [GOA01, Wang04]
GO:0005975 - carbohydrate metabolic process Inferred by computational analysis [GOA01]
Molecular Function: GO:0016810 - hydrolase activity, acting on carbon-nitrogen (but not peptide) bonds Inferred from experiment Inferred by computational analysis [GOA01, Itoh08]
GO:0003824 - catalytic activity Inferred by computational analysis [GOA01]
GO:0016787 - hydrolase activity Inferred by computational analysis [UniProtGOA11]
Cellular Component: GO:0009279 - cell outer membrane Inferred by computational analysis [UniProtGOA11a, UniProtGOA11]
GO:0016020 - membrane Inferred by computational analysis [UniProtGOA11]

MultiFun Terms: metabolism biosynthesis of macromolecules (cellular constituents)

Credits:
Imported from EcoCyc 16-Sep-2014 by Paley S , SRI International


Enzymatic reaction of: poly-β-1,6-N-acetyl-D-glucosamine N-deacetylase

poly-β-1,6-N-acetyl-D-glucosamine + H2O <=> partially N-deacetylated poly-β-1,6-N-acetyl-D-glucosamine + acetate + H+

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction in which it was curated.

Reversibility of this reaction is unspecified.

Credits:
Imported from EcoCyc 16-Sep-2014 by Paley S , SRI International


Sequence Features

Feature Class Location Common Name Citations Comment
Signal-Sequence 1 -> 20 PgaB signal sequence
[Itoh08]
 
Chain 21 -> 672  
[UniProt09]
UniProt: Biofilm PGA synthesis lipoprotein pgaB;
Lipid-Binding-Site 21 PgaB palmitoylation site
[Itoh08]
 
Conserved-Region 107 -> 349  
[UniProt14]
UniProt: NodB homology.
Mutagenesis-Variant 115  
[Itoh08, UniProt11]
Alternate sequence: A; UniProt: High decrease in catalytic activity. Unable to support biofilm formation and PGA secretion.
Mutagenesis-Variant 184  
[Itoh08, UniProt11]
Alternate sequence: A; UniProt: Unable to support biofilm formation and PGA secretion.

History:
Markus Krummenacker on Tue Oct 14, 1997:
Gene object created from Blattner lab Genbank (v. M52) entry.


References

Agladze05: Agladze K, Wang X, Romeo T (2005). "Spatial periodicity of Escherichia coli K-12 biofilm microstructure initiates during a reversible, polar attachment phase of development and requires the polysaccharide adhesin PGA." J Bacteriol 187(24);8237-46. PMID: 16321928

Cerca08: Cerca N, Jefferson KK (2008). "Effect of growth conditions on poly-N-acetylglucosamine expression and biofilm formation in Escherichia coli." FEMS Microbiol Lett 283(1);36-41. PMID: 18445167

GOA01: GOA, DDB, FB, MGI, ZFIN (2001). "Gene Ontology annotation through association of InterPro records with GO terms."

Goller06: Goller C, Wang X, Itoh Y, Romeo T (2006). "The cation-responsive protein NhaR of Escherichia coli activates pgaABCD transcription, required for production of the biofilm adhesin poly-beta-1,6-N-acetyl-D-glucosamine." J Bacteriol 188(23);8022-32. PMID: 16997959

Itoh05: Itoh Y, Wang X, Hinnebusch BJ, Preston JF, Romeo T (2005). "Depolymerization of beta-1,6-N-acetyl-D-glucosamine disrupts the integrity of diverse bacterial biofilms." J Bacteriol 187(1);382-7. PMID: 15601723

Itoh08: Itoh Y, Rice JD, Goller C, Pannuri A, Taylor J, Meisner J, Beveridge TJ, Preston JF, Romeo T (2008). "Roles of pgaABCD genes in synthesis, modification, and export of the Escherichia coli biofilm adhesin poly-beta-1,6-N-acetyl-D-glucosamine." J Bacteriol 190(10);3670-80. PMID: 18359807

Jones99: Jones HA, Lillard JW, Perry RD (1999). "HmsT, a protein essential for expression of the haemin storage (Hms+) phenotype of Yersinia pestis." Microbiology 145 ( Pt 8);2117-28. PMID: 10463178

Mercante06: Mercante J, Suzuki K, Cheng X, Babitzke P, Romeo T (2006). "Comprehensive alanine-scanning mutagenesis of Escherichia coli CsrA defines two subdomains of critical functional importance." J Biol Chem 281(42);31832-42. PMID: 16923806

UniProt09: UniProt Consortium (2009). "UniProt version 15.8 released on 2009-10-01 00:00:00." Database.

UniProt11: UniProt Consortium (2011). "UniProt version 2011-06 released on 2011-06-30 00:00:00." Database.

UniProt14: UniProt Consortium (2014). "UniProt version 2014-01 released on 2014-01-01 00:00:00." Database.

UniProtGOA11: UniProt-GOA (2011). "Gene Ontology annotation based on manual assignment of UniProtKB keywords in UniProtKB/Swiss-Prot entries."

UniProtGOA11a: UniProt-GOA (2011). "Gene Ontology annotation based on the manual assignment of UniProtKB Subcellular Location terms in UniProtKB/Swiss-Prot entries."

Wang04: Wang X, Preston JF, Romeo T (2004). "The pgaABCD locus of Escherichia coli promotes the synthesis of a polysaccharide adhesin required for biofilm formation." J Bacteriol 186(9);2724-34. PMID: 15090514

Wang05: Wang X, Dubey AK, Suzuki K, Baker CS, Babitzke P, Romeo T (2005). "CsrA post-transcriptionally represses pgaABCD, responsible for synthesis of a biofilm polysaccharide adhesin of Escherichia coli." Mol Microbiol 56(6);1648-63. PMID: 15916613


Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by SRI International Pathway Tools version 18.5 on Sun Dec 21, 2014, BIOCYC13B.