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Escherichia coli K-12 substr. MG1655 Enzyme: maltodextrin glucosidase



Gene: malZ Accession Numbers: EG10565 (EcoCyc), b0403, ECK0397

Regulation Summary Diagram: ?

Summary:
Maltodextrin glucosidase catalyzes the hydrolysis of short malto-oligosaccharides ranging from maltotriose to maltoheptaose, liberating glucose from the reducing end. Final products of the reaction are glucose and maltose [Tapio91]. To a small extent, the enzyme can directly release maltose from maltodextrins longer than maltotriose [Peist96]. Maltodextrin glucosidase also hydrolyzes γ-cyclodextrin, which contains eight glucosyl residues; however, γ-cyclodextrin is not transported by E. coli and is thus not a physiological substrate [Peist96]. The enzyme can also act as a transglycosylase [Song10a].

The enzyme may play a role in regulating the intracellular level of maltotriose, the inducer of the mal regulon: overexpression of malZ results in decreased expression of the other mal genes [Tapio91].

GroEL-GroES- and chemical chaperone-assisted folding of MalZ has been studied [Paul07a, Paul07b, Paul08, Paul08a].

A malZ mutant is able to grow well on short malto-oligosaccharides [Tapio91] and is able to degrade dextrins to maltotriose [Dippel05]. The malZ292 allele supresses the Mal- defect of a malQ mutant by acquiring dextrinyl transferase activity, but not the ability to hydrolyze maltose [Peist96]. A malZ mutant contains increased levels of glycogen when grown on maltose or maltodextrin, and overexpression of MalZ in a ΔmalP glgA mutant decreses the amount of glycogen when grown on maltose [Park11a].

Expression of malZ is dependent on the MalT regulator [Reyes86], but is also induced by high osmolarity even in the absence of MalT; this effect is not dependent on RpoS or OmpR [Dippel05a].

Locations: cytosol

Map Position: [421,742 -> 423,556] (9.09 centisomes)
Length: 1815 bp / 604 aa

Molecular Weight of Polypeptide: 69.041 kD (from nucleotide sequence), 65 kD (experimental) [Tapio91 ]

pI: 6.26

Unification Links: ASAP:ABE-0001402 , CGSC:29868 , DIP:DIP-10152N , EchoBASE:EB0560 , EcoGene:EG10565 , EcoliWiki:b0403 , Mint:MINT-1219352 , ModBase:P21517 , OU-Microarray:b0403 , PortEco:malZ , PR:PRO_000023158 , Protein Model Portal:P21517 , RefSeq:NP_414937 , RegulonDB:EG10565 , SMR:P21517 , String:511145.b0403 , UniProt:P21517

Relationship Links: CAZy:IN-FAMILY:CBM34 , CAZy:IN-FAMILY:GH13 , InterPro:IN-FAMILY:IPR004185 , InterPro:IN-FAMILY:IPR006047 , InterPro:IN-FAMILY:IPR006589 , InterPro:IN-FAMILY:IPR013780 , InterPro:IN-FAMILY:IPR013781 , InterPro:IN-FAMILY:IPR014756 , InterPro:IN-FAMILY:IPR015902 , InterPro:IN-FAMILY:IPR017069 , InterPro:IN-FAMILY:IPR017853 , Panther:IN-FAMILY:PTHR10357 , Pfam:IN-FAMILY:PF00128 , Pfam:IN-FAMILY:PF02903 , Smart:IN-FAMILY:SM00642

In Paralogous Gene Group: 123 (6 members)

Gene-Reaction Schematic: ?

Genetic Regulation Schematic: ?

GO Terms:

Biological Process: GO:0030980 - alpha-glucan catabolic process Inferred from experiment [Tapio91]
GO:0051692 - cellular oligosaccharide catabolic process Inferred from experiment [Dippel05]
GO:0000023 - maltose metabolic process Inferred by computational analysis [UniProtGOA11]
GO:0005975 - carbohydrate metabolic process Inferred by computational analysis [GOA01]
GO:0008152 - metabolic process Inferred by computational analysis [UniProtGOA11]
Molecular Function: GO:0004558 - alpha-1,4-glucosidase activity Inferred from experiment Inferred by computational analysis [GOA01a, GOA01, Tapio91]
GO:0003824 - catalytic activity Inferred by computational analysis [GOA01]
GO:0004553 - hydrolase activity, hydrolyzing O-glycosyl compounds Inferred by computational analysis [GOA01]
GO:0016787 - hydrolase activity Inferred by computational analysis [UniProtGOA11]
GO:0016798 - hydrolase activity, acting on glycosyl bonds Inferred by computational analysis [UniProtGOA11]
GO:0032450 - maltose alpha-glucosidase activity Inferred by computational analysis [GOA01a]
GO:0043169 - cation binding Inferred by computational analysis [GOA01]
Cellular Component: GO:0005737 - cytoplasm Inferred from experiment Inferred by computational analysis [UniProtGOA11a, UniProtGOA11, GOA01, Reyes86]
GO:0005829 - cytosol Inferred by computational analysis [DiazMejia09, Reyes86]

MultiFun Terms: metabolism carbon utilization carbon compounds
metabolism degradation of macromolecules polysaccharides

Essentiality data for malZ knockouts: ?

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

Credits:
Last-Curated ? 31-Mar-2011 by Keseler I , SRI International


Enzymatic reaction of: maltoheptaose glucosidase (maltodextrin glucosidase)

EC Number: 3.2.1.20

maltoheptaose + H2O <=> maltohexaose + α-D-glucose

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction of enzyme catalysis.

The reaction is physiologically favored in the direction shown.


Enzymatic reaction of: maltohexaose glucosidase (maltodextrin glucosidase)

EC Number: 3.2.1.20

maltohexaose + H2O <=> maltopentaose + α-D-glucose

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction of enzyme catalysis.

The reaction is physiologically favored in the direction shown.


Enzymatic reaction of: maltopentaose glucosidase (maltodextrin glucosidase)

EC Number: 3.2.1.20

maltopentaose + H2O <=> maltotetraose + α-D-glucose

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction of enzyme catalysis.

The reaction is physiologically favored in the direction shown.


Enzymatic reaction of: maltodextrin glucosidase

Synonyms: α-glucosidae, maltase-glucoamylase, α-D-glucoside glucohydrolase

EC Number: 3.2.1.20

maltotriose + H2O <=> maltose + D-glucopyranose

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction of enzyme catalysis.

The reaction is physiologically favored in the direction shown.

EC Number: 3.2.1.20

(1,4-α-D-glucosyl)(n) + H2O <=> (1,4-α-D-glucosyl)(n-1) + α-D-glucose

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction of enzyme catalysis.

The reaction is physiologically favored in the direction shown.

Alternative Substrates for maltotriose [Comment 5 ]: γ-cyclodextrin [Peist96 ] , cycloamylose [Song10a ]

Alternative Products for D-glucopyranose [Comment 5 ]: maltose [Peist96 ]

In Pathways: glycogen degradation I

Summary:
Hydrolyzable substrates range from maltoheptaose to maltotriose. The Kms for the various substrates are as follows: maltotriose, 25 mM; maltotetraose, 5.6 mM; maltopentaose, 2.9 mM; maltohexaose, 1.9 mM; maltoheptaose, 3.4 mM. The Vmax is highest with maltotriose (65.6 mmol min-1 mg-1) [Tapio91].

T(opt): 37 °C [Song10a]

pH(opt): 7 [Tapio91]


Sequence Features

Feature Class Location Citations Comment
Sequence-Conflict 301
[Tapio91, UniProt10]
Alternate sequence: L → M; UniProt: (in Ref. 1; CAA42498);
Active-Site 336
[UniProt10a]
UniProt: Nucleophile; Non-Experimental Qualifier: by similarity;
Active-Site 373
[UniProt10a]
UniProt: Proton donor; Non-Experimental Qualifier: by similarity;
Sequence-Conflict 445
[Tapio91, UniProt10]
Alternate sequence: D → E; UniProt: (in Ref. 1; CAA42498);
Active-Site 448
[UniProt10a]
UniProt: Non-Experimental Qualifier: by similarity;
Sequence-Conflict 546
[Tapio91, UniProt10]
Alternate sequence: R → S; UniProt: (in Ref. 1; CAA42498);


Gene Local Context (not to scale): ?

Transcription Unit:

Notes:

History:
Ingrid Keseler on Fri Oct 7, 2011:
Gene start position adjusted based on computational analysis by K. Rudd.
10/20/97 Gene b0403 from Blattner lab Genbank (v. M52) entry merged into EcoCyc gene EG10565; confirmed by SwissProt match.


References

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

DiazMejia09: Diaz-Mejia JJ, Babu M, Emili A (2009). "Computational and experimental approaches to chart the Escherichia coli cell-envelope-associated proteome and interactome." FEMS Microbiol Rev 33(1);66-97. PMID: 19054114

Dippel05: Dippel R, Boos W (2005). "The maltodextrin system of Escherichia coli: metabolism and transport." J Bacteriol 187(24);8322-31. PMID: 16321936

Dippel05a: Dippel R, Bergmiller T, Bohm A, Boos W (2005). "The maltodextrin system of Escherichia coli: glycogen-derived endogenous induction and osmoregulation." J Bacteriol 187(24);8332-9. PMID: 16321937

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

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

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

GOA01a: GOA, MGI (2001). "Gene Ontology annotation based on Enzyme Commission mapping." Genomics 74;121-128.

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

Park11a: Park JT, Shim JH, Tran PL, Hong IH, Yong HU, Oktavina EF, Nguyen HD, Kim JW, Lee TS, Park SH, Boos W, Park KH (2011). "Role of maltose enzymes in glycogen synthesis by Escherichia coli." J Bacteriol 193(10);2517-26. PMID: 21421758

Paul07a: Paul S, Singh C, Mishra S, Chaudhuri TK (2007). "The 69 kDa Escherichia coli maltodextrin glucosidase does not get encapsulated underneath GroES and folds through trans mechanism during GroEL/GroES-assisted folding." FASEB J 21(11);2874-85. PMID: 17494995

Paul07b: Paul S, Punam S, Chaudhuri TK (2007). "Chaperone-assisted refolding of Escherichia coli maltodextrin glucosidase." FEBS J 274(22);6000-10. PMID: 17983358

Paul08: Paul S, Chaudhuri TK (2008). "Chaperone mediated solubilization of 69-kDa recombinant maltodextrin glucosidase in Escherichia coli." J Appl Microbiol 104(1);35-41. PMID: 18171380

Paul08a: Paul S, Kundu M, Das KP, Mishra S, Chaudhuri TK (2008). "Unfolding studies of Escherichia coli maltodextrin glucosidase monitored by fluorescence spectroscopy." J Biol Phys 34(6);539-50. PMID: 19669512

Peist96: Peist R, Schneider-Fresenius C, Boos W (1996). "The MalT-dependent and malZ-encoded maltodextrin glucosidase of Escherichia coli can be converted into a dextrinyltransferase by a single mutation." J Biol Chem 271(18);10681-9. PMID: 8631875

Reyes86: Reyes M, Treptow NA, Shuman HA (1986). "Transport of p-nitrophenyl-alpha-maltoside by the maltose transport system of Escherichia coli and its subsequent hydrolysis by a cytoplasmic alpha-maltosidase." J Bacteriol 165(3);918-22. PMID: 3512530

Song10a: Song KM, Shim JH, Park JT, Kim SH, Kim YW, Boos W, Park KH (2010). "Transglycosylation properties of maltodextrin glucosidase (MalZ) from Escherichia coli and its application for synthesis of a nigerose-containing oligosaccharide." Biochem Biophys Res Commun 397(1);87-92. PMID: 20493171

Tapio91: Tapio S, Yeh F, Shuman HA, Boos W (1991). "The malZ gene of Escherichia coli, a member of the maltose regulon, encodes a maltodextrin glucosidase." J Biol Chem 1991;266(29);19450-8. PMID: 1918057

UniProt10: UniProt Consortium (2010). "UniProt version 2010-11 released on 2010-11-02 00:00:00." Database.

UniProt10a: UniProt Consortium (2010). "UniProt version 2010-07 released on 2010-06-15 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."


Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of EcoCyc: Nucleic Acids Research 41:D605-12 2013
Page generated by SRI International Pathway Tools version 18.5 on Wed Nov 26, 2014, BIOCYC13B.