Accepted name: protein-lysine 6-oxidase
Reaction: [protein]-L-lysine + O2 + H2O = [protein]-(S)-2-amino-6-oxohexanoate + NH3 + H2O2
Glossary: (S)-2-amino-6-oxohexanoate = L-allysine
Other name(s): lysyl oxidase
Systematic name: protein-L-lysine:oxygen 6-oxidoreductase (deaminating)
Comments: Also acts on protein 5-hydroxylysine. This enzyme catalyses the final known enzymic step required for collagen and elastin cross-linking in the biosynthesis of normal mature extracellular matrices [4]. These reactions play an important role for the development, elasticity and extensibility of connective tissue. The enzyme is also active on free amines, such as cadaverine or benzylamine [4,5]. Some isoforms can also use [protein]-N(6)-acetyl-L-lysine as substrate deacetamidating the substrate [6].
1.  Harris, E.D., Gonnerman, W.A., Savage, J.E. and O'Dell, B.L. Connective tissue amine oxidase. II. Purification and partial characterization of lysyl oxidase from chick aorta. Biochim. Biophys. Acta 341 (1974) 332–344. [PMID: 4838158]
2.  Rayton, J.K. and Harris, E.D. Induction of lysyl oxidase with copper. Properties of an in vitro system. J. Biol. Chem. 254 (1979) 621–626. [PMID: 33171]
3.  Stassen, F.L.H. Properties of highly purified lysyl oxidase from embryonic chick cartilage. Biochim. Biophys. Acta 438 (1976) 49–60. [PMID: 7318]
4.  Palamakumbura, A.H. and Trackman, P.C. A fluorometric assay for detection of lysyl oxidase enzyme activity in biological samples. Anal. Biochem. 300 (2002) 245–251. [PMID: 11779117]
5.  Kagan, H.M., Williams, M.A., Williamson, P.R. and Anderson, J.M. Influence of sequence and charge on the specificity of lysyl oxidase toward protein and synthetic peptide substrates. J. Biol. Chem. 259 (1984) 11203–11207. [PMID: 6147351]
6.  Rodriguez, H.M., Vaysberg, M., Mikels, A., McCauley, S., Velayo, A.C., Garcia, C. and Smith, V. Modulation of lysyl oxidase-like 2 enzymatic activity by an allosteric antibody inhibitor. J. Biol. Chem. 285 (2010) 20964–20974. [PMID: 20439985]
7.  Kim, Y.M., Kim, E.C. and Kim, Y. The human lysyl oxidase-like 2 protein functions as an amine oxidase toward collagen and elastin. Mol. Biol. Rep. 38 (2011) 145–149. [PMID: 20306300]
8.  Xu, L., Go, E.P., Finney, J., Moon, H., Lantz, M., Rebecchi, K., Desaire, H. and Mure, M. Post-translational modifications of recombinant human lysyl oxidase-like 2 (rhLOXL2) secreted from Drosophila S2 cells. J. Biol. Chem. 288 (2013) 5357–5363. [PMID: 23319596]
9.  Ma, L., Huang, C., Wang, X.J., Xin, D.E., Wang, L.S., Zou, Q.C., Zhang, Y.S., Tan, M.D., Wang, Y.M., Zhao, T.C., Chatterjee, D., Altura, R.A., Wang, C., Xu, Y.S., Yang, J.H., Fan, Y.S., Han, B.H., Si, J., Zhang, X., Cheng, J., Chang, Z. and Chin, Y.E. Lysyl oxidase 3 is a dual-specificity enzyme involved in STAT3 deacetylation and deacetylimination modulation. Mol. Cell 65 (2017) 296–309. [PMID: 28065600]
[EC created 1980, modified 1983]
Accepted name: L-lysine 6-oxidase
Reaction: L-lysine + O2 + H2O = (S)-2-amino-6-oxohexanoate + H2O2 + NH3
Glossary: (S)-2-amino-6-oxohexanoate = L-2-aminoadipate 6-semialdehyde = L-allysine
Other name(s): L-lysine-ε-oxidase; Lod; LodA; marinocine
Systematic name: L-lysine:oxygen 6-oxidoreductase (deaminating)
Comments: Differs from EC, protein-lysine 6-oxidase, by using free L-lysine rather than the protein-bound form. N2-Acetyl-L-lysine is also a substrate, but N6-acetyl-L-lysine, which has an acetyl group at position 6, is not a substrate. Also acts on L-ornithine, D-lysine and 4-hydroxy-L-lysine, but more slowly. The amines cadaverine and putrescine are not substrates [2].
1.  Lucas-Elío, P., Gómez, D., Solano, F. and Sanchez-Amat, A. The antimicrobial activity of marinocine, synthesized by Marinomonas mediterranea, is due to hydrogen peroxide generated by its lysine oxidase activity. J. Bacteriol. 188 (2006) 2493–2501. [PMID: 16547036]
2.  Gómez, D., Lucas-Elío, P., Sanchez-Amat, A. and Solano, F. A novel type of lysine oxidase: L-lysine-ε-oxidase. Biochim. Biophys. Acta 1764 (2006) 1577–1585. [PMID: 17030025]
[EC created 2006, modified 2011]
Accepted name: N8-acetylspermidine oxidase (propane-1,3-diamine-forming)
Reaction: N8-acetylspermidine + O2 + H2O = propane-1,3-diamine + 4-acetamidobutanal + H2O2
Systematic name: N8-acetylspermidine:oxygen oxidoreductase (propane-1,3-diamine-forming)
Comments: Also active with N1-acetylspermine, weak activity with N1,N12-diacetylspermine. No activity with diaminopropane, putrescine, cadaverine, diaminohexane, norspermidine, spermine and spermidine. Absence of monoamine oxidase (EC activity. Differs in specificity from EC (N1-acetylpolyamine oxidase), EC (polyamine oxidase (propane-1,3-diamine-forming)), EC (spermine oxidase) and EC (non-specific polyamine oxidase).
1.  Shukla, O.P., Muller, S. and Walter, R.D. Polyamine oxidase from Acanthamoeba culbertsoni specific for N8-acetylspermidine. Mol. Biochem. Parasitol. 51 (1992) 91–98. [PMID: 1565141]
[EC created 2009]
Accepted name: spermidine synthase
Reaction: S-adenosyl 3-(methylsulfanyl)propylamine + putrescine = S-methyl-5′-thioadenosine + spermidine
Glossary: spermidine = N-(3-aminopropyl)butane-1,4-diamine
spermine = N,N′-bis(3-aminopropyl)butane-1,4-diamine
putrescine = butane-1,4-diamine
S-adenosyl 3-(methylsulfanyl)propylamine = (3-aminopropyl){[(2S,3S,4R,5R)-5-(6-amino-9H-purin-9-yl)-3,4-dihydroxytetrahydrofuran-2-yl]methyl}methylsulfonium
Other name(s): aminopropyltransferase; putrescine aminopropyltransferase; spermidine synthetase; SpeE (ambiguous); S-adenosylmethioninamine:putrescine 3-aminopropyltransferase; S-adenosyl 3-(methylthio)propylamine:putrescine 3-aminopropyltransferase
Systematic name: S-adenosyl 3-(methylsulfanyl)propylamine:putrescine 3-aminopropyltransferase
Comments: The enzymes from the plant Glycine max and from mammalia are highly specific for putrescine as the amine acceptor [2,7]. The enzymes from the bacteria Escherichia coli and Thermotoga maritima prefer putrescine but are more tolerant towards other amine acceptors, such as spermidine and cadaverine [5,6]. cf. EC (spermine synthase) and EC (sym-norspermidine synthase).
1.  Hannonen, P., Janne, J. and Raina, A. Partial purification and characterization of spermine synthase from rat brain. Biochim. Biophys. Acta 289 (1972) 225–231. [PMID: 4564056]
2.  Pegg, A.E., Shuttleworth, K. and Hibasami, H. Specificity of mammalian spermidine synthase and spermine synthase. Biochem. J. 197 (1981) 315–320. [PMID: 6798961]
3.  Tabor, C.W. Propylamine transferase (spermidine synthesis). Methods Enzymol. 5 (1962) 761–765.
4.  Tabor, H. and Tabor, C.W. Biosynthesis and metabolism of 1,4-diaminobutane, spermidine, spermine, and related amines. Adv. Enzymol. Relat. Areas Mol. Biol. 36 (1972) 203–268. [PMID: 4628436]
5.  Bowman, W.H., Tabor, C.W. and Tabor, H. Spermidine biosynthesis. Purification and properties of propylamine transferase from Escherichia coli. J. Biol. Chem. 248 (1973) 2480–2486. [PMID: 4572733]
6.  Korolev, S., Ikeguchi, Y., Skarina, T., Beasley, S., Arrowsmith, C., Edwards, A., Joachimiak, A., Pegg, A.E. and Savchenko, A. The crystal structure of spermidine synthase with a multisubstrate adduct inhibitor. Nat. Struct. Biol. 9 (2002) 27–31. [PMID: 11731804]
7.  Yoon, S.O., Lee, Y.S., Lee, S.H. and Cho, Y.D. Polyamine synthesis in plants: isolation and characterization of spermidine synthase from soybean (Glycine max) axes. Biochim. Biophys. Acta 1475 (2000) 17–26. [PMID: 10806333]
[EC created 1972, modified 1982, modified 2013]
Accepted name: N1-aminopropylagmatine synthase
Reaction: S-adenosyl 3-(methylsulfanyl)propylamine + agmatine = S-methyl-5′-thioadenosine + N1-(3-aminopropyl)agmatine
Glossary: S-adenosyl 3-(methylsulfanyl)propylamine = (3-aminopropyl){[(2S,3S,4R,5R)-5-(6-amino-9H-purin-9-yl)-3,4-dihydroxytetrahydrofuran-2-yl]methyl}methylsulfonium
Other name(s): agmatine/cadaverine aminopropyl transferase; ACAPT; PF0127 (gene name); triamine/agmatine aminopropyltransferase; SpeE (ambiguous); agmatine aminopropyltransferase; S-adenosyl 3-(methylthio)propylamine:agmatine 3-aminopropyltransferase
Systematic name: S-adenosyl 3-(methylsulfanyl)propylamine:agmatine 3-aminopropyltransferase
Comments: The enzyme is involved in the biosynthesis of spermidine from agmatine in some archaea and bacteria. The enzyme from the Gram-negative bacterium Thermus thermophilus accepts agmatine, spermidine and norspermidine with similar catalytic efficiency. The enzymes from the archaea Pyrococcus furiosus and Thermococcus kodakarensis prefer agmatine, but can utilize cadaverine, putrescine and propane-1,3-diamine with much lower catalytic efficiency. cf. EC, spermidine synthase, and EC, sym-norspermidine synthase.
1.  Ohnuma, M., Terui, Y., Tamakoshi, M., Mitome, H., Niitsu, M., Samejima, K., Kawashima, E. and Oshima, T. N1-aminopropylagmatine, a new polyamine produced as a key intermediate in polyamine biosynthesis of an extreme thermophile, Thermus thermophilus. J. Biol. Chem. 280 (2005) 30073–30082. [PMID: 15983049]
2.  Cacciapuoti, G., Porcelli, M., Moretti, M.A., Sorrentino, F., Concilio, L., Zappia, V., Liu, Z.J., Tempel, W., Schubot, F., Rose, J.P., Wang, B.C., Brereton, P.S., Jenney, F.E. and Adams, M.W. The first agmatine/cadaverine aminopropyl transferase: biochemical and structural characterization of an enzyme involved in polyamine biosynthesis in the hyperthermophilic archaeon Pyrococcus furiosus. J. Bacteriol. 189 (2007) 6057–6067. [PMID: 17545282]
3.  Morimoto, N., Fukuda, W., Nakajima, N., Masuda, T., Terui, Y., Kanai, T., Oshima, T., Imanaka, T. and Fujiwara, S. Dual biosynthesis pathway for longer-chain polyamines in the hyperthermophilic archaeon Thermococcus kodakarensis. J. Bacteriol. 192 (2010) 4991–5001. [PMID: 20675472]
4.  Ohnuma, M., Ganbe, T., Terui, Y., Niitsu, M., Sato, T., Tanaka, N., Tamakoshi, M., Samejima, K., Kumasaka, T. and Oshima, T. Crystal structures and enzymatic properties of a triamine/agmatine aminopropyltransferase from Thermus thermophilus. J. Mol. Biol. 408 (2011) 971–986. [PMID: 21458463]
[EC created 2013]
Accepted name: putrescine—2-oxoglutarate transaminase
Reaction: putrescine + 2-oxoglutarate = 4-aminobutanal + L-glutamate
Glossary: putrescine = butane-1,4-diamine
1-pyrroline = 3,4-dihydro-2H-pyrrole
Other name(s): putrescine-α-ketoglutarate transaminase; YgjG; putrescine:α-ketoglutarate aminotransferase; PAT (ambiguous); putrescine transaminase (ambiguous); putrescine aminotransferase (ambiguous); butane-1,4-diamine:2-oxoglutarate aminotransferase
Systematic name: putrescine:2-oxoglutarate aminotransferase
Comments: A pyridoxal 5′-phosphate protein [3]. The product, 4-aminobutanal, spontaneously cyclizes to form 1-pyrroline, which may be the actual substrate for EC, aminobutyraldehyde dehydrogenase. Cadaverine and spermidine can also act as substrates [3]. Forms part of the arginine-catabolism pathway [2]. cf. EC, putrescine—pyruvate transaminase.
1.  Prieto-Santos, M.I., Martin-Checa, J., Balaña-Fouce, R. and Garrido-Pertierra, A. A pathway for putrescine catabolism in Escherichia coli. Biochim. Biophys. Acta 880 (1986) 242–244. [PMID: 3510672]
2.  Samsonova, N.N., Smirnov, S.V., Novikova, A.E. and Ptitsyn, L.R. Identification of Escherichia coli K12 YdcW protein as a γ-aminobutyraldehyde dehydrogenase. FEBS Lett. 579 (2005) 4107–4112. [PMID: 16023116]
3.  Samsonova, N.N., Smirnov, S.V., Altman, I.B. and Ptitsyn, L.R. Molecular cloning and characterization of Escherichia coli K12 ygjG gene. BMC Microbiol. 3 (2003) 2. [PMID: 12617754]
[EC created 2006, modified 2017, modified 2021]
Accepted name: acetylputrescine deacetylase
Reaction: N-acetylputrescine + H2O = acetate + putrescine
Glossary: putrescine = butane-1,4-diamine
spermidine = N-(3-aminopropyl)butane-1,4-diamine
Systematic name: N-acetylputrescine acetylhydrolase
Comments: The enzyme from Micrococcus luteus also acts on N8-acetylspermidine and acetylcadaverine, but more slowly.
1.  Suzuki, O., Ishikawa, Y., Miyazaki, K., Izu, K. and Matsumoto, T. Acetylputrescine deacetylase from Micrococcus luteus K-11. Biochim. Biophys. Acta 882 (1986) 140–142.
[EC created 1989]
Accepted name: lysine decarboxylase
Reaction: L-lysine = cadaverine + CO2
Other name(s): L-lysine carboxy-lyase
Systematic name: L-lysine carboxy-lyase (cadaverine-forming)
Comments: A pyridoxal-phosphate protein. Also acts on 5-hydroxy-L-lysine.
1.  Gale, E.F. and Epps, H.M.R. Studies on bacterial amino-acid decarboxylases. 1. l(+)-lysine decarboxylase. Biochem. J. 38 (1944) 232–242. [PMID: 16747785]
2.  Soda, K. and Moriguchi, M. Crystalline lysine decarboxylase. Biochem. Biophys. Res. Commun. 34 (1969) 34–39. [PMID: 5762458]
[EC created 1961]
Accepted name: D-ornithine/D-lysine decarboxylase
Reaction: (1) D-ornithine = putrescine + CO2
(2) D-lysine = cadaverine + CO2
Glossary: cadaverine = pentane-1,5-diamine
putrescine = butane-1,4-diamine
Other name(s): dokD (gene name); DOKDC
Systematic name: D-ornithine/D-lysine carboxy-lyase
Comments: The enzyme, characterized from the bacterium Salmonella typhimurium LT2, is specific for D-ornithine and D-lysine. Requires pyridoxal 5′-phosphate.
1.  Phillips, R.S., Poteh, P., Miller, K.A. and Hoover, T.R. STM2360 encodes a D-ornithine/D-lysine decarboxylase in Salmonella enterica serovar typhimurium. Arch. Biochem. Biophys. 634 (2017) 83–87. [PMID: 29024617]
[EC created 2019]