|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions|
|Reactions Classified By Substrate → Macromolecule Reactions → Polynucleotide-Reactions → RNA-Reactions → tRNA-Reactions → tRNA-Charging-Reactions|
EC Number: 22.214.171.124
In Pathway: L-cysteine biosynthesis II (RNA-dependent)
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.
Most BioCyc compounds have been protonated to a reference pH value of 7.3, and some reactions have been computationally balanced for hydrogen by adding free protons. Please see the PGDB Concepts Guide for more information.
Mass balance status: Balanced.
Enzyme Commission Primary Name: O-phospho-L-serine—tRNA ligase
Enzyme Commission Synonyms: O-phosphoseryl-tRNA ligase, non-canonical O-phosphoseryl-tRNA synθse, SepRS
Standard Gibbs Free Energy (ΔrG'° in kcal/mol): -61.770264 [Latendresse13]
Enzyme Commission Summary:
In organisms like Archaeoglobus fulgidus lacking EC 126.96.36.199 (canonical cysteinyl-tRNA synthetase) for the direct Cys-tRNACys formation, Cys-tRNACys is produced by an indirect pathway, in which O-phosphoseryl-tRNA ligase ligates the noncanonical amino acid O-phosphoserine to tRNACys, and the Sep-tRNA:Cys-tRNA synthase converts the produced Sep-tRNACys to Cys-tRNACys, the SepRS/SepCysS pathway is the sole route for cysteine biosynthesis in the organism [Fukunaga07]. Methanosarcina mazei can use both pathways, the canonical route using EC 188.8.131.52 and the indirect pathway [Hauenstein08].
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