EC Number   |
General Information |
Reference |
|---|
    2.6.1.45 | evolution |
phylogenetic analysis and tree |
-, 758661 |
| 2.6.1.45 | malfunction |
elevated SGAT activity through transgenic overexpression of Flaveria pringlei SGAT causes clear changes in metabolism and interferes with photosynthetic CO2 uptake and biomass accumulation of Arabidopsis. The faster serine turnover during photorespiration progressively lowers day-time leaf serine contents and in turn induces the phosphoserine pathway. Transcriptional upregulation of this additional route of serine biosynthesis occurs already during the day but particularly at night, efficiently counteracting night-time serine depletion. Additionally, higher SGAT activity results in an increased use of asparagine as the external donor of amino groups to the photorespiratory pathway but does not alter leaf asparagine content at night. These results suggest leaf SGAT activity needs to be dynamically adjusted to ensure (i) variable flux through the photorespiratory pathway at a minimal consumption of asparagine and (ii) adequate serine levels for other cellular metabolism, phenotype analysis. Impact of excess SGAT activity on the photorespiratory pathway and photorespiratory nitrogen cycling, schematic overview |
-, 759565 |
| 2.6.1.45 | malfunction |
the disruption of the sga gene in Methylomicrobium alcaliphilum results in retardation of growth rate of the mutant cells and in a prolonged lag-phase after passaging from methane to methanol. In addition, the growth of the mutant strain is accompanied by formaldehyde accumulation in the culture liquid |
-, 758661 |
| 2.6.1.45 | metabolism |
enzymic activity within the cell gradually decreases with the increase of cell density. Activity is significantly affected by light intensity and growth in presence of acetate as sole carbon source. Activity increases in presence of high oxygen concentrations and high carbon dioxide concentrations. An increase in oxygen concentration additionally results in a raise of cellular Gly/Ser ratio from 0.79 to 1.49 |
723450 |
| 2.6.1.45 | metabolism |
serine-glyoxylate aminotransferase (Sga) is the indicator enzyme of the serine pathway of assimilation of reduced C1 compounds |
-, 758661 |
| 2.6.1.45 | metabolism |
serine:glyoxylate aminotransferase (SGAT) converts glyoxylate and serine to glycine and hydroxypyruvate during photorespiration. Besides this, SGAT operates with several other substrates including asparagine, impact of this enzymatic promiscuity on plant metabolism, particularly photorespiration and serine biosynthesis, overview |
-, 759565 |
| 2.6.1.45 | more |
in the enzyme crystal, another dimer related by noncrystallographic symmetry makes close interactions to form a tetramer mediated in part by an extra carboxyl-terminal helix conserved in plant homologues of AGT1. Residues Tyr35' and Arg36', entering the active site from the other subunits in the dimer, mediate interactions between AGT and L-serine when used as a substrate. Structural model of AGT1 and structure-function analysis, structure comparisons, detailed overview |
759257 |
| 2.6.1.45 | more |
influence of metabolites on the activity of recombinant serineglyoxylate aminotransferase, overview |
-, 758661 |
| 2.6.1.45 | physiological function |
Arabidopsis thaliana serine:glyoxylate aminotransferase (AGT1) is a multifunctional class IV aminotransferase protein that catalyzes transamination reactions using L-serine, L-alanine, and L-asparagine as amino donors and glyoxylate, pyruvate, and hydroxypyruvate as amino acceptors. AGT1 is a peroxisomal aminotransferase with a central role in photorespiration. This enzyme catalyzes various aminotransferase reactions, including serine:glyoxylate, alanine:glyoxylate, and asparagine:glyoxylate transaminations |
759257 |
| 2.6.1.45 | physiological function |
overexpression in Lemna minor results in increased enzymic activity and decreased endogenous serine levels under salt stress, leading to enhanced protection against root abscission, higher maximum quantum yield of photosystem II, increased defense from cell damage as a result of improved cell membrane integrity, a decrease of reactive oxygen species accumulation, and a strengthened antioxidant system |
723401 |
