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Pathway Description
Spermidine Biosynthesis I
Escherichia coli O111:H- str. 11128
Category:
Metabolite Pathway
Sub-Category:
Metabolic
Created: 2025-02-09
Last Updated: 2025-06-17
Spermidine is formed from decarboxy-SAM and putrescine by catalyzing spermidine synthase (also knowns as polyamine aminopropyltransferase). The source of putrescine is transported from outside of cell by putrescine/spermidine ABC transporter. Decarboxy-SAM comes from S-Adenosylmethionine with catalyzation of adenosylmethionine decarboxylase and cofactors: pyruvic acid and magnesium. The other product of the aminopropyltransferase reaction is S-methyl-5'-thioadenosine (MTA), which can be recycled back to L-methionine in many organisms, but not in E. coli. Inhibition of E. coli adenosylmethionine decarboxylase by spermidine appears to be the most significant regulator of polyamine biosynthesis, probably limiting it when the intracellular spermidine concentration becomes excessive. In E. coli most intracellular spermidine is bound to nucleic acids and phospholipids. (EcoCyc)
References
Spermidine Biosynthesis I References
Tabor CW, Tabor H: The speEspeD operon of Escherichia coli. Formation and processing of a proenzyme form of S-adenosylmethionine decarboxylase. J Biol Chem. 1987 Nov 25;262(33):16037-40.
Pubmed: 3316212
Fujita N, Mori H, Yura T, Ishihama A: Systematic sequencing of the Escherichia coli genome: analysis of the 2.4-4.1 min (110,917-193,643 bp) region. Nucleic Acids Res. 1994 May 11;22(9):1637-9. doi: 10.1093/nar/22.9.1637.
Pubmed: 8202364
Blattner FR, Plunkett G 3rd, Bloch CA, Perna NT, Burland V, Riley M, Collado-Vides J, Glasner JD, Rode CK, Mayhew GF, Gregor J, Davis NW, Kirkpatrick HA, Goeden MA, Rose DJ, Mau B, Shao Y: The complete genome sequence of Escherichia coli K-12. Science. 1997 Sep 5;277(5331):1453-62. doi: 10.1126/science.277.5331.1453.
Pubmed: 9278503
Xie QW, Tabor CW, Tabor H: Spermidine biosynthesis in Escherichia coli: promoter and termination regions of the speED operon. J Bacteriol. 1989 Aug;171(8):4457-65. doi: 10.1128/jb.171.8.4457-4465.1989.
Pubmed: 2666401
Tabor CW, Tabor H, Xie QW: Spermidine synthase of Escherichia coli: localization of the speE gene. Proc Natl Acad Sci U S A. 1986 Aug;83(16):6040-4. doi: 10.1073/pnas.83.16.6040.
Pubmed: 3526348
Kashiwagi K, Miyamoto S, Nukui E, Kobayashi H, Igarashi K: Functions of potA and potD proteins in spermidine-preferential uptake system in Escherichia coli. J Biol Chem. 1993 Sep 15;268(26):19358-63.
Pubmed: 8366082
Furuchi T, Kashiwagi K, Kobayashi H, Igarashi K: Characteristics of the gene for a spermidine and putrescine transport system that maps at 15 min on the Escherichia coli chromosome. J Biol Chem. 1991 Nov 5;266(31):20928-33.
Pubmed: 1939142
Oshima T, Aiba H, Baba T, Fujita K, Hayashi K, Honjo A, Ikemoto K, Inada T, Itoh T, Kajihara M, Kanai K, Kashimoto K, Kimura S, Kitagawa M, Makino K, Masuda S, Miki T, Mizobuchi K, Mori H, Motomura K, Nakamura Y, Nashimoto H, Nishio Y, Saito N, Horiuchi T, et al.: A 718-kb DNA sequence of the Escherichia coli K-12 genome corresponding to the 12.7-28.0 min region on the linkage map. DNA Res. 1996 Jun 30;3(3):137-55. doi: 10.1093/dnares/3.3.137.
Pubmed: 8905232
This pathway was propagated using PathWhiz -
Pon, A. et al. Pathways with PathWhiz (2015) Nucleic Acids Res. 43(Web Server issue): W552–W559.
Propagated from SMP0002054
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