Escherichia coli K-12 substr. MG1655 Enzyme: biosynthetic peptidoglycan transglycosylase

Gene: mtgA Accession Numbers: G7668 (EcoCyc), b3208, ECK3197

Synonyms: mgt, yrbM

Regulation Summary Diagram: ?

Regulation summary diagram for mtgA

MtgA is a monofunctional peptidoglycan transglycosylase involved in polymerization of lipid II molecules into glycan strands of peptidoglycan.

GFP-MtgA fusions localize to the division site in mrcA(ts) mrcB mutants [Derouaux08]. Bacterial two-hybrid experiments reveal MtgA interacts with PBP3, FtsW, and FtsN [Derouaux08].

Assays for peptidoglycan synthesis activity revealed that MtgA has glycosyltransferase activity and polymerizes glycan strands with lipid II as substrate at an optimum pH of 6.0 to 6.5 [Hara84, Di96, Derouaux08]. This differs from the optimum of 7.5 to 8.0 for PBP1B, which is the major bifunctional glycosyltransferase for peptidoglycan synthesis in E. coli [Hara84, Di96]. The glycan strands were then shown to act as substrate for lysozyme [Hara84, Di96, Derouaux08]. Inhibition assays show that Flavomycin does not inhibit this activity as it does with the high-molecular-weight penicillin-binding proteins that have glycosyltransferase activity [Di96].

Induction of this gene from an expression vector in wild-type W3110 caused cells to immediately stop growing, but not to lyse [Di96]. mtgA mutants and mtgA pbpC double mutants have elevated levels of tetrapenta muropeptides [Schiffer99].

Ofloxacin downregulates mtgA expression [Kaldalu04].

Citations: [Faure04, Spratt96]

Locations: cell wall, inner membrane

Map Position: [3,347,103 <- 3,347,831] (72.14 centisomes, 260°)
Length: 729 bp / 242 aa

Molecular Weight of Polypeptide: 27.342 kD (from nucleotide sequence), 27 kD (experimental) [Di96 ]

Unification Links: ASAP:ABE-0010530 , DIP:DIP-10266N , EchoBASE:EB2659 , EcoGene:EG12808 , EcoliWiki:b3208 , Mint:MINT-1226871 , ModBase:P46022 , OU-Microarray:b3208 , PortEco:mtgA , PR:PRO_000023302 , Protein Model Portal:P46022 , RefSeq:NP_417675 , RegulonDB:G7668 , SMR:P46022 , String:511145.b3208 , UniProt:P46022

Relationship Links: CAZy:IN-FAMILY:GT51 , InterPro:IN-FAMILY:IPR001264 , InterPro:IN-FAMILY:IPR011812 , InterPro:IN-FAMILY:IPR023346 , Pfam:IN-FAMILY:PF00912

In Paralogous Gene Group: 50 (4 members)

Gene-Reaction Schematic: ?

Gene-Reaction Schematic

GO Terms:

Biological Process: GO:0009252 - peptidoglycan biosynthetic process Inferred from experiment Inferred by computational analysis [UniProtGOA12, UniProtGOA11, GOA06, GOA01, Derouaux08, Di96, Hara84]
GO:0043164 - Gram-negative-bacterium-type cell wall biogenesis Inferred from experiment [Derouaux08, Di96, Hara84]
GO:0008360 - regulation of cell shape Inferred by computational analysis [UniProtGOA11]
GO:0071555 - cell wall organization Inferred by computational analysis [UniProtGOA11]
Molecular Function: GO:0005515 - protein binding Inferred from experiment [Rajagopala14, Derouaux08]
GO:0008955 - peptidoglycan glycosyltransferase activity Inferred from experiment [Derouaux08, Di96, Hara84]
GO:0016740 - transferase activity Inferred by computational analysis [UniProtGOA11]
GO:0016763 - transferase activity, transferring pentosyl groups Inferred by computational analysis [GOA06, GOA01]
Cellular Component: GO:0005886 - plasma membrane Inferred from experiment Inferred by computational analysis [UniProtGOA11a, UniProtGOA11, GOA06, DiazMejia09, Di96]
GO:0009274 - peptidoglycan-based cell wall Inferred by computational analysis [GOA01]
GO:0016020 - membrane Inferred by computational analysis [UniProtGOA11]
GO:0016021 - integral component of membrane Inferred by computational analysis [UniProtGOA11, GOA01]

MultiFun Terms: cell structure murein
metabolism biosynthesis of macromolecules (cellular constituents) murein (peptidoglycan)

Essentiality data for mtgA 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]

Last-Curated ? 07-Jan-2009 by Johnson A , JCVI

Enzymatic reaction of: peptidoglycan glycosyltransferase (biosynthetic peptidoglycan transglycosylase)

EC Number:

a nascent [peptidoglycan]n with (L-alanyl-γ-D-glutamyl-meso-2,6-diaminopimeloyl-D-alanyl-D-alanine) pentapeptide[periplasmic space] + ditrans,octacis-undecaprenyldiphospho-N-acetyl-(N-acetylglucosaminyl)muramoyl-L-alanyl-γ-D-glutamyl-meso-2,6-diaminopimeloyl-D-alanyl-D-alanine[periplasmic space] <=> a nascent [peptidoglycan]n+1 with (L-alanyl-γ-D-glutamyl-meso-2,6-diaminopimeloyl-D-alanyl-D-alanine) pentapeptide[periplasmic space] + di-trans,octa-cis-undecaprenyl diphosphate[periplasmic space]

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.

The reaction is physiologically favored in the direction shown.

In Pathways: peptidoglycan maturation (meso-diaminopimelate containing)

Cofactors or Prosthetic Groups: Ca2+ [Hara84], Mn2+ [Hara84], Co2+ [Hara84]

Inhibitors (Unknown Mechanism): vancomycin [Hara84] , EDTA [Hara84]

Sequence Features

Protein sequence of biosynthetic peptidoglycan transglycosylase with features indicated

Feature Class Location Common Name Citations Comment
Transmembrane-Region 19 -> 39  
UniProt: Helical;; Non-Experimental Qualifier: potential;
Transmembrane-Region 19 -> 46 MtgA transmembrane segment

Gene Local Context (not to scale): ?

Gene local context diagram

Transcription Unit:

Transcription-unit diagram


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

Derouaux08: Derouaux A, Wolf B, Fraipont C, Breukink E, Nguyen-Disteche M, Terrak M (2008). "The monofunctional glycosyltransferase of Escherichia coli localizes to the cell division site and interacts with penicillin-binding protein 3, FtsW, and FtsN." J Bacteriol 190(5);1831-4. PMID: 18165305

Di96: Di Berardino M, Dijkstra A, Stuber D, Keck W, Gubler M (1996). "The monofunctional glycosyltransferase of Escherichia coli is a member of a new class of peptidoglycan-synthesising enzymes." FEBS Lett 392(2);184-8. PMID: 8772200

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

Faure04: Faure D, Frederick R, Wloch D, Portier P, Blot M, Adams J (2004). "Genomic changes arising in long-term stab cultures of Escherichia coli." J Bacteriol 186(19);6437-42. PMID: 15375124

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."

GOA06: GOA, SIB (2006). "Electronic Gene Ontology annotations created by transferring manual GO annotations between orthologous microbial proteins."

Hara84: Hara H, Suzuki H (1984). "A novel glycan polymerase that synthesizes uncross-linked peptidoglycan in Escherichia coli." FEBS Lett 168(1);155-60. PMID: 6368264

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

Kaldalu04: Kaldalu N, Mei R, Lewis K (2004). "Killing by ampicillin and ofloxacin induces overlapping changes in Escherichia coli transcription profile." Antimicrob Agents Chemother 48(3);890-6. PMID: 14982780

Rajagopala14: Rajagopala SV, Sikorski P, Kumar A, Mosca R, Vlasblom J, Arnold R, Franca-Koh J, Pakala SB, Phanse S, Ceol A, Hauser R, Siszler G, Wuchty S, Emili A, Babu M, Aloy P, Pieper R, Uetz P (2014). "The binary protein-protein interaction landscape of Escherichia coli." Nat Biotechnol 32(3);285-90. PMID: 24561554

Schiffer99: Schiffer G, Holtje JV (1999). "Cloning and characterization of PBP 1C, a third member of the multimodular class A penicillin-binding proteins of Escherichia coli." J Biol Chem 274(45);32031-9. PMID: 10542235

Spratt96: Spratt BG, Zhou J, Taylor M, Merrick MJ (1996). "Monofunctional biosynthetic peptidoglycan transglycosylases." Mol Microbiol 19(3);639-40. PMID: 8830253

UniProt10: 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."

UniProtGOA12: UniProt-GOA (2012). "Gene Ontology annotation based on UniPathway vocabulary mapping."

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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 19.0 on Mon Oct 5, 2015, biocyc13.