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Escherichia coli K-12 substr. MG1655 Polypeptide: fructose PTS permease - FruB subunit

Gene: fruB Accession Numbers: G7990 (EcoCyc), b2169, ECK2162

Synonyms: fpr, fruF, diphosphoryl transfer protein, DTP, EIIA-M-Hfru, EIIAfru, Enzyme IIAfru, EIIIfru, Enzyme IIIfru

Regulation Summary Diagram

Regulation summary diagram for fruB

Component of: fructose PTS permease (extended summary available)

Alternative forms of fructose PTS permease - FruB subunit: FruB - his299 phosphorylated (summary available)

E. coli fruB encodes a tridomain protein in which a IIA domain is linked to an HPr-like domain called FPr (fructose-inducible HPr) or H by a central domain (M) of unknown function [Reizer94, Geerse86, Geerse89a]. Phosphate transfer to fructose by the fructose PTS occurs via the FPr domain of FruB rather than by HPr as is typical for other PTS pathways [Kornberg86]. Phosphate transfer is predicted to occur from Enzyme I (PtsI) to histidine residue 299 in the FruB H domain to histidine residue 62 in the FruB IIA domain.

FruB is also known as the diphosphoryl transfer protein (DTP).

Citations: [Waygood80]

Gene Citations: [Dobrynina95]

Locations: inner membrane, cytosol

Map Position: [2,260,387 <- 2,261,517] (48.72 centisomes, 175°)
Length: 1131 bp / 376 aa

Molecular Weight of Polypeptide: 39.648 kD (from nucleotide sequence)

Unification Links: ASAP:ABE-0007180, DIP:DIP-48096N, EchoBASE:EB0005, EcoGene:EG10005, EcoliWiki:b2169, Mint:MINT-1263101, ModBase:P69811, OU-Microarray:b2169, PortEco:fruB, PR:PRO_000022700, Pride:P69811, Protein Model Portal:P69811, RefSeq:NP_416674, RegulonDB:G7990, SMR:P69811, String:511145.b2169, Swiss-Model:P69811, UniProt:P69811

Relationship Links: InterPro:IN-FAMILY:IPR000032, InterPro:IN-FAMILY:IPR001020, InterPro:IN-FAMILY:IPR002114, InterPro:IN-FAMILY:IPR002178, InterPro:IN-FAMILY:IPR016152, Pfam:IN-FAMILY:PF00359, Pfam:IN-FAMILY:PF00381, Prints:IN-FAMILY:PR00107, Prosite:IN-FAMILY:PS00369, Prosite:IN-FAMILY:PS00372, Prosite:IN-FAMILY:PS00589, Prosite:IN-FAMILY:PS51094, Prosite:IN-FAMILY:PS51350

In Paralogous Gene Group: 187 (14 members)

In Reactions of unknown directionality:

Not in pathways:
BglG + FruB-Phis299 = FruB + BglG-Phis208

Gene-Reaction Schematic

Gene-Reaction Schematic

Instance reaction of [D-fructose[periplasm] + PtsI-Phis189 → D-fructose 1-phosphate[cytosol] + PtsI] (no EC#):
i1: β-D-fructofuranose[periplasm] + PtsI-Phis189 → β-D-fructofuranose 1-phosphate[cytosol] + PtsI (no EC#)

Genetic Regulation Schematic

Genetic regulation schematic for fruB

GO Terms:
Biological Process:
Inferred from experimentInferred by computational analysisGO:0009401 - phosphoenolpyruvate-dependent sugar phosphotransferase system [UniProtGOA11a, Waygood80]
Inferred from experimentGO:0032445 - fructose import [Waygood80]
Inferred by computational analysisGO:0006810 - transport [UniProtGOA11a, GOA01a]
Inferred by computational analysisGO:0008643 - carbohydrate transport [UniProtGOA11a]
Inferred by computational analysisGO:0016310 - phosphorylation [UniProtGOA11a]
Molecular Function:
Inferred from experimentGO:0022877 - protein-N(PI)-phosphohistidine-fructose phosphotransferase system transporter activity [Waygood80]
Inferred by computational analysisGO:0005215 - transporter activity [GOA01a]
Inferred by computational analysisGO:0016301 - kinase activity [UniProtGOA11a]
Inferred by computational analysisGO:0016740 - transferase activity [UniProtGOA11a]
Cellular Component:
Inferred from experimentGO:0019897 - extrinsic component of plasma membrane [Waygood80]
Inferred by computational analysisGO:0005737 - cytoplasm [UniProtGOA11, UniProtGOA11a]

MultiFun Terms: metabolismcarbon utilizationcarbon compounds
transportGroup TranslocatorsPhosphotransferase Systems (PEP-dependent PTS)

Essentiality data for fruB knockouts:

Growth Medium Growth? T (°C) O2 pH Osm/L Growth Observations
LB enrichedYes 37 Aerobic 6.95   Yes [Gerdes03, Comment 1]
LB LennoxYes 37 Aerobic 7   Yes [Baba06, Comment 2]
M9 medium with 1% glycerolYes 37 Aerobic 7.2 0.35 Yes [Joyce06, Comment 3]
MOPS medium with 0.4% glucoseYes 37 Aerobic 7.2 0.22 Yes [Baba06, Comment 2]
Yes [Feist07, Comment 4]

Subunit of: fructose PTS permease

Synonyms: EIIFru, Enzyme IIFru

Subunit composition of fructose PTS permease = [FruB][FruA]2
         fructose PTS permease - FruB subunit = FruB (summary available)
         fructose PTS permease - FruA subunit = FruA (summary available)

FruAB, the fructose PTS permease, belongs to the functional superfamily of the phosphoenolpyruvate (PEP)-dependent, sugar transporting phosphotransferase system (PTSsugar). The PTSsugar transports and simultaneously phosphorylates its substrates in a process called group translocation. FruAB takes up fructose, releasing the 1-phosphate ester into the cytoplasm in preparation for metabolism, primarily via glycolysis (reviewed in [Postma93]).

FruAB, also known as the Enzyme IIFru complex contains a unique combination of PTS domains with three domains in the FruA (IIB'-IIB-IIC) protein [Prior88] and three domains in the FruB protein (IIA-M-H). In the FruB protein, domain IIA contains the first phosphorylation site, M is a central domain of unknown function, and H (also known as pseudo HPr) substitutes for HPr in the phosphoryl transfer reaction [Waygood80, Kornberg86, Geerse86, Geerse89a, Reizer94]. FruB is also known as the diphosphoryl transfer protein (DTP). The IIB and IIB' domains of the FruA protein are localized to the cytoplasmic side of the membrane. The IIB' domain may be required for binding of FruB to FruA [Charbit96]. FruAB is a member of the PTS Fructose-Mannitol (Fru) family of transporters [Saier14].

The overall PTS-mediated phosphoryl transfer reaction, requiring the general energy coupling protein of the PTS, Enzyme I (PtsI) as well as the FruAB complex can be represented as:

PEP → Enzyme I-Phis189 → Enzyme IIA-Phis299 → Enzyme IIA-Phis62 → Enzyme IIB-Pcys112 - (Enzyme IIC) → fructose-1-P.

FruAB transports fructose with low micromolar affinity. FruAB transports mannose with low efficiency (Km > 5 mM). Mannose is taken up by the FruAB PTS to form mannose-6-phosphate [Kornberg92]

Expression of the fru (fruBKA) operon is regulated by the fructose repressor, FruR, also known as the catabolite repressor/activator (Cra) protein [Ramseier93, Shimada11a]. The fru operon is also subject to positive control by the cyclic AMP-cyclic AMP receptor protein (CRP) complex.

Reviews: [Kornberg90]

Citations: [Kornberg01, Waygood84 ]

GO Terms:
Biological Process:
Inferred from experimentGO:0009401 - phosphoenolpyruvate-dependent sugar phosphotransferase system [Prior88]
Inferred from experimentGO:0015761 - mannose transport [Kornberg92]
Inferred from experimentGO:0032445 - fructose import [Prior88]
Molecular Function:
Inferred from experimentGO:0090582 - protein-phosphocysteine-D-fructose-phosphotransferase system transporter activity [Charbit96]

Last-Curated 06-Mar-2014 by Mackie A, Macquarie University

Enzymatic reaction of: transport and phosphorylation of D-fructose (fructose PTS permease)

Inferred from experimentInferred by computational analysis

Transport reaction diagram for transport and phosphorylation of D-fructose

Enzymatic reaction of: transport and phosphorylation of D-fructofuranose (fructose PTS permease)

Inferred from experimentInferred by computational analysis

Transport reaction diagram for transport and phosphorylation of D-fructofuranose

Sequence Features

Protein sequence of fructose PTS permease - FruB subunit with features indicated

Feature Class Location Citations Comment State
Conserved-Region 2 -> 142
Inferred by computational analysis[UniProt15]
UniProt: PTS EIIA type-2.
Pfam PF00359 5 -> 139
Inferred by computational analysis[Finn14]
PTS_EIIA_2 : Phosphoenolpyruvate-dependent sugar phosphotransferase system, EIIA 2
Sequence-Conflict 59
Inferred by curator[Itoh96, UniProt15]
UniProt: (in Ref. 3).
Active-Site 62
Inferred by computational analysis[UniProt15]
UniProt: Tele-phosphohistidine intermediate; for EIIA activity.
Protein-Segment 156 -> 284
Author statement[UniProt15]
UniProt: M domain; Sequence Annotation Type: region of interest.
Conserved-Region 285 -> 375
Inferred by computational analysis[UniProt15]
UniProt: HPr.
Pfam PF00381 287 -> 368
Inferred by computational analysis[Finn14]
PTS-HPr : PTS HPr component phosphorylation site
Active-Site 299
Inferred by computational analysis[UniProt15]
UniProt: Pros-phosphohistidine intermediate; for HPr activity.
Tele-phosphohistidine-Modification 299
Inferred by computational analysis[UniProt10]
UniProt: Pros-phosphohistidine intermediate; for HPr activity; Non-Experimental Qualifier: by similarity;

Gene Local Context (not to scale -- see Genome Browser for correct scale)

Gene local context diagram

Transcription Unit

Transcription-unit diagram


4/27/1998 (ptoole) Merged genes G415/EG10005 and G7990/fruB The genes fruB and fpr are easily confused; fpr is a synonym for fruB, but fruB is not a synonym for fpr.
Markus Krummenacker on Tue Oct 14, 1997:
Gene object created from Blattner lab Genbank (v. M52) entry.


Baba06: Baba T, Ara T, Hasegawa M, Takai Y, Okumura Y, Baba M, Datsenko KA, Tomita M, Wanner BL, Mori H (2006). "Construction of Escherichia coli K-12 in-frame, single-gene knockout mutants: the Keio collection." Mol Syst Biol 2;2006.0008. PMID: 16738554

Charbit96: Charbit A, Reizer J, Saier MH (1996). "Function of the duplicated IIB domain and oligomeric structure of the fructose permease of Escherichia coli." J Biol Chem 271(17);9997-10003. PMID: 8626640

Dobrynina95: Dobrynina OIu, Bol'shakova TN, Umiarov AM, Gershanovich VN (1995). "[Determination of the direction of transcription of Escherichia coli K-12 structural genes of the fructose regulon in vivo]." Genetika 31(2);276-7. PMID: 7721070

Feist07: Feist AM, Henry CS, Reed JL, Krummenacker M, Joyce AR, Karp PD, Broadbelt LJ, Hatzimanikatis V, Palsson BO (2007). "A genome-scale metabolic reconstruction for Escherichia coli K-12 MG1655 that accounts for 1260 ORFs and thermodynamic information." Mol Syst Biol 3;121. PMID: 17593909

Finn14: Finn RD, Bateman A, Clements J, Coggill P, Eberhardt RY, Eddy SR, Heger A, Hetherington K, Holm L, Mistry J, Sonnhammer EL, Tate J, Punta M (2014). "Pfam: the protein families database." Nucleic Acids Res 42(Database issue);D222-30. PMID: 24288371

Geerse86: Geerse RH, Ruig CR, Schuitema AR, Postma PW (1986). "Relationship between pseudo-HPr and the PEP: fructose phosphotransferase system in Salmonella typhimurium and Escherichia coli." Mol Gen Genet 203(3);435-44. PMID: 3528748

Geerse89a: Geerse RH, Izzo F, Postma PW (1989). "The PEP: fructose phosphotransferase system in Salmonella typhimurium: FPr combines enzyme IIIFru and pseudo-HPr activities." Mol Gen Genet 216(2-3);517-25. PMID: 2546043

Gerdes03: Gerdes SY, Scholle MD, Campbell JW, Balazsi G, Ravasz E, Daugherty MD, Somera AL, Kyrpides NC, Anderson I, Gelfand MS, Bhattacharya A, Kapatral V, D'Souza M, Baev MV, Grechkin Y, Mseeh F, Fonstein MY, Overbeek R, Barabasi AL, Oltvai ZN, Osterman AL (2003). "Experimental determination and system level analysis of essential genes in Escherichia coli MG1655." J Bacteriol 185(19);5673-84. PMID: 13129938

GOA01a: GOA, DDB, FB, MGI, ZFIN (2001). "Gene Ontology annotation through association of InterPro records with GO terms."

Itoh96: Itoh T, Aiba H, Baba T, Hayashi K, Inada T, Isono K, Kasai H, Kimura S, Kitakawa M, Kitagawa M, Makino K, Miki T, Mizobuchi K, Mori H, Mori T, Motomura K, Nakade S, Nakamura Y, Nashimoto H, Nishio Y, Oshima T, Saito N, Sampei G, Seki Y, Horiuchi T (1996). "A 460-kb DNA sequence of the Escherichia coli K-12 genome corresponding to the 40.1-50.0 min region on the linkage map." DNA Res 3(6);379-92. PMID: 9097040

Joyce06: Joyce AR, Reed JL, White A, Edwards R, Osterman A, Baba T, Mori H, Lesely SA, Palsson BO, Agarwalla S (2006). "Experimental and computational assessment of conditionally essential genes in Escherichia coli." J Bacteriol 188(23);8259-71. PMID: 17012394

Kornberg01: Kornberg HL (2001). "Routes for fructose utilization by Escherichia coli." J Mol Microbiol Biotechnol 3(3);355-9. PMID: 11361065

Kornberg86: Kornberg H (1986). "The roles of HPr and FPr in the utilization of fructose by Escherichia coli." FEBS Lett 194(1);12-5. PMID: 3510127

Kornberg90: Kornberg HL (1990). "Fructose transport by Escherichia coli." Philos Trans R Soc Lond B Biol Sci 326(1236);505-13. PMID: 1970653

Kornberg92: Kornberg HL, Lambourne LT (1992). "Role of the phosphoenolpyruvate-dependent fructose phosphotransferase system in the utilization of mannose by Escherichia coli." Proc Biol Sci 250(1327);51-5. PMID: 1361062

Postma93: Postma PW, Lengeler JW, Jacobson GR (1993). "Phosphoenolpyruvate:carbohydrate phosphotransferase systems of bacteria." Microbiol Rev 57(3);543-94. PMID: 8246840

Prior88: Prior TI, Kornberg HL (1988). "Nucleotide sequence of fruA, the gene specifying enzyme IIfru of the phosphoenolpyruvate-dependent sugar phosphotransferase system in Escherichia coli K12." J Gen Microbiol 1988;134 ( Pt 10);2757-68. PMID: 3076173

Ramseier93: Ramseier TM, Negre D, Cortay JC, Scarabel M, Cozzone AJ, Saier MH (1993). "In vitro binding of the pleiotropic transcriptional regulatory protein, FruR, to the fru, pps, ace, pts and icd operons of Escherichia coli and Salmonella typhimurium." J Mol Biol 234(1);28-44. PMID: 8230205

Reizer94: Reizer J, Reizer A, Kornberg HL, Saier MH (1994). "Sequence of the fruB gene of Escherichia coli encoding the diphosphoryl transfer protein (DTP) of the phosphoenolpyruvate: sugar phosphotransferase system." FEMS Microbiol Lett 1994;118(1-2);159-62. PMID: 8013873

Saier14: Saier MH, Reddy VS, Tamang DG, Vastermark A (2014). "The transporter classification database." Nucleic Acids Res 42(1);D251-8. PMID: 24225317

Shimada11a: Shimada T, Yamamoto K, Ishihama A (2011). "Novel Members of the Cra Regulon Involved in Carbon Metabolism in Escherichia coli." J Bacteriol 193(3);649-59. PMID: 21115656

UniProt10: UniProt Consortium (2010). "UniProt version 2010-07 released on 2010-06-15 00:00:00." Database.

UniProt15: UniProt Consortium (2015). "UniProt version 2015-08 released on 2015-07-22." Database.

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

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

Waygood80: Waygood EB (1980). "Resolution of the phosphoenolpyruvate: fructose phosphotransferase system of Escherichia coli into two components: enzyme IIfructose and fructose-induced HPr-like protein (FPr)." Can J Biochem 58(10);1144-6. PMID: 7006754

Waygood84: Waygood EB, Mattoo RL, Peri KG (1984). "Phosphoproteins and the phosphoenolpyruvate: sugar phosphotransferase system in Salmonella typhimurium and Escherichia coli: evidence for IIImannose, IIIfructose, IIIglucitol, and the phosphorylation of enzyme IImannitol and enzyme IIN-acetylglucosamine." J Cell Biochem 25(3);139-59. PMID: 6434550

Other References Related to Gene Regulation

Huerta03: Huerta AM, Collado-Vides J (2003). "Sigma70 promoters in Escherichia coli: specific transcription in dense regions of overlapping promoter-like signals." J Mol Biol 333(2);261-78. PMID: 14529615

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Please cite the following article in publications resulting from the use of EcoCyc: Nucleic Acids Research 41:D605-12 2013
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