4.2.1.108 (2S)-4-acetamido-2-aminobutanoate - Sphingopyxis alaskensis L-ectoine + H2O - ? 444080 4.2.1.108 (2S)-4-acetamido-2-aminobutanoate - Sphingopyxis alaskensis DSM 13593 / LMG 18877 / RB2256 L-ectoine + H2O - ? 444080 4.2.1.108 D,L-4,5-dihydro-2-methylimidazole-4-carboxylate + H2O - Halomonas elongata ? - r 416809 4.2.1.108 D,L-4,5-dihydro-2-methylimidazole-4-carboxylate + H2O - Halomonas elongata DSM 2581 ? - r 416809 4.2.1.108 L-glutamine - Halomonas elongata 5-amino-3,4-dihydro-2H-pyrrole-2-carboxylate + H2O - r 417147 4.2.1.108 L-glutamine - Halomonas elongata DSM 2581 5-amino-3,4-dihydro-2H-pyrrole-2-carboxylate + H2O - r 417147 4.2.1.108 L-homoectoine + H2O - Halomonas elongata ? - r 417153 4.2.1.108 N-alpha-acetyl-L-2,4-diaminobutanoate - Sphingopyxis alaskensis L-ectoine + H2O - ? 445723 4.2.1.108 N-alpha-acetyl-L-2,4-diaminobutanoate - Sphingopyxis alaskensis DSM 13593 / LMG 18877 / RB2256 L-ectoine + H2O - ? 445723 4.2.1.108 N4-acetyl-L-2,4-diaminobutyrate - Halalkalibacterium halodurans 2-methyl-1,4,5,6-tetrahydropyrimidine-4-carboxylic acid + H2O - ? 398955 4.2.1.108 N4-acetyl-L-2,4-diaminobutyrate - Halalkalibacterium halodurans TCJAR021 2-methyl-1,4,5,6-tetrahydropyrimidine-4-carboxylic acid + H2O - ? 398955 4.2.1.108 N4-acetyl-L-2,4-diaminobutyrate - Halalkalibacterium halodurans L-ectoine + H2O - ? 398956 4.2.1.108 N4-acetyl-L-2,4-diaminobutyrate - Halalkalibacterium halodurans TCJAR021 L-ectoine + H2O - ? 398956 4.2.1.108 N4-acetyl-L-2,4-diaminobutanoate an intramolecular condensation reaction Halomonas elongata L-ectoine + H2O - r 415694 4.2.1.108 N4-acetyl-L-2,4-diaminobutanoate an intramolecular condensation reaction Halomonas elongata L-ectoine + H2O i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid, over 95% conversion by the recombinant ectoine synthase r 415694 4.2.1.108 N4-acetyl-L-2,4-diaminobutanoate an intramolecular condensation reaction Halomonas elongata DSM 2581 L-ectoine + H2O - r 415694 4.2.1.108 N4-acetyl-L-2,4-diaminobutanoate an intramolecular condensation reaction Halomonas elongata DSM 2581 L-ectoine + H2O i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid, over 95% conversion by the recombinant ectoine synthase r 415694 4.2.1.108 additional information EctC not only effectively converts its natural substrate N-gamma-acetyl-L-2,4-diaminobutyric acid into ectoine through a cyclocondensation reaction, but it can also use the isomer N-alpha-acetyl-L-2,4-diaminobutyric acid as its substrate, albeit with substantially reduced catalytic efficiency Sphingopyxis alaskensis ? - ? 89 4.2.1.108 additional information EctC not only effectively converts its natural substrate N-gamma-acetyl-L-2,4-diaminobutyric acid into ectoine through a cyclocondensation reaction, but it can also use the isomer N-alpha-acetyl-L-2,4-diaminobutyric acid as its substrate, albeit with substantially reduced catalytic efficiency Sphingopyxis alaskensis DSM 13593 / LMG 18877 / RB2256 ? - ? 89 4.2.1.108 additional information ectoine synthase accepts more than one substrate and is a reversible enzyme able to catalyze both the intramolecular condensation into and the hydrolytic cleavage of cyclic amino acid derivatives. It forms 5-amino-3,4-dihydro-2H-pyrrole-2-carboxylate, ADPC, by cyclic condensation of glutamine in a reversible reaction. A number of ectoine derivatives, in particular 4,5-dihydro-2-methylimidazole-4-carboxylate and L-homoectoine, are also cleaved by ectoine synthase. Proposed reaction mechanism leading to L-ectoine and 5-amino-3,4-dihydro-2H-pyrrole-2-carboxylate, respectively, catalyzed by ectoine synthase, overview Halomonas elongata ? - ? 89 4.2.1.108 additional information ectoine synthase accepts more than one substrate and is a reversible enzyme able to catalyze both the intramolecular condensation into and the hydrolytic cleavage of cyclic amino acid derivatives. It forms 5-amino-3,4-dihydro-2H-pyrrole-2-carboxylate, ADPC, by cyclic condensation of glutamine in a reversible reaction. A number of ectoine derivatives, in particular 4,5-dihydro-2-methylimidazole-4-carboxylate and L-homoectoine, are also cleaved by ectoine synthase. Proposed reaction mechanism leading to L-ectoine and 5-amino-3,4-dihydro-2H-pyrrole-2-carboxylate, respectively, catalyzed by ectoine synthase, overview Halomonas elongata DSM 2581 ? - ? 89 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, L-ectoine acts as an osmoprotectant Virgibacillus pantothenticus L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, L-ectoine acts as an osmoprotectant Alkalihalobacillus alcalophilus L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, L-ectoine acts as an osmoprotectant Sporosarcina psychrophila L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, L-ectoine acts as an osmoprotectant Sporosarcina pasteurii L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, L-ectoine acts as an osmoprotectant Virgibacillus salexigens L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, L-ectoine acts as an osmoprotectant Chromohalobacter salexigens L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, L-ectoine is the compatible solute in the cell Halomonas elongata L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, L-ectoine is the compatible solute in the cell Halomonas elongata OUT30018 L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, pathway overview Halorhodospira halochloris L-ectoine + H2O - r 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, pathway overview Halomonas elongata L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, pathway overview Marinococcus halophilus L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, pathway overview Methylotuvimicrobium alcaliphilum L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, pathway overview Halomonas elongata OUT300318 L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, pathway overview Halomonas elongata OUT30018 L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate final step in L-ectoine biosynthesis, pathway overview, L-ectoine is the main compatible solute in the organism with a cytoplasmic concentration of 1-2 M Halomonas elongata L-ectoine + H2O - r 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Halomonas elongata L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Marinococcus halophilus L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Halomonas elongata L-ectoine + H2O NMR and thin layer chromatography product identification r 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Halorhodospira halochloris L-ectoine + H2O NMR and TLC product identification r 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Sporosarcina psychrophila L-ectoine + H2O NMR identification ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Sporosarcina pasteurii L-ectoine + H2O NMR identification ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Virgibacillus pantothenticus L-ectoine + H2O NMR product identification ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Alkalihalobacillus alcalophilus L-ectoine + H2O NMR product identification ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Virgibacillus salexigens L-ectoine + H2O NMR product identification ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Methylotuvimicrobium alcaliphilum L-ectoine + H2O NMR product identification r 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Chromohalobacter salexigens L-ectoine + H2O NMR product identification ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid Halomonas elongata OUT30018 L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid, circularization, L-ectoine as an effective osmoprotectant, the enzyme shows absolute substrate specificity, reversibility of the reaction is not detected but might be below detection range Halomonas elongata L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid, circularization, L-ectoine as an effective osmoprotectant, the enzyme shows absolute substrate specificity, reversibility of the reaction is not detected but might be below detection range Halomonas elongata OUT300318 L-ectoine + H2O - ? 378394 4.2.1.108 4-N-acetyl-L-2,4-diaminobutanoate i.e. 1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid, circularization, L-ectoine as an effective osmoprotectant, the enzyme shows absolute substrate specificity, reversibility of the reaction is not detected but might be below detection range Halomonas elongata OUT30018 L-ectoine + H2O - ? 378394 4.2.1.108 (2S)-4-acetamido-2-aminobutanoate i.e. N-gamma-acetyl-L-2,4-diaminobutanoate Sphingopyxis alaskensis L-ectoine + H2O - ? 444080 4.2.1.108 (2S)-4-acetamido-2-aminobutanoate i.e. N-gamma-acetyl-L-2,4-diaminobutanoate Sphingopyxis alaskensis DSM 13593 / LMG 18877 / RB2256 L-ectoine + H2O - ? 444080 4.2.1.108 additional information phylogenetic analysis Virgibacillus pantothenticus ? - ? 89 4.2.1.108 additional information phylogenetic analysis Alkalihalobacillus alcalophilus ? - ? 89 4.2.1.108 additional information phylogenetic analysis Sporosarcina psychrophila ? - ? 89 4.2.1.108 additional information phylogenetic analysis Sporosarcina pasteurii ? - ? 89 4.2.1.108 additional information phylogenetic analysis Virgibacillus salexigens ? - ? 89 4.2.1.108 additional information phylogenetic analysis Chromohalobacter salexigens ? - ? 89 4.2.1.108 additional information the enzyme is osmoregulated in response to medium salinity allowing the organism to live in environments with high concentration of osmolytes Marinococcus halophilus ? - ? 89