View Ontology Report


Homocysteine (Hcy) metabolism is at the cross-roads of several pathways and is itself a byproduct of the de novo pathway of the methionine metabolic cycle. Hcy can be methylated to methionine via the cobalamin-dependent and independent pathways. The first is the predominant reaction in most tissues and is carried out by methionine synthase (Mtr). The requirement for the 1 carbon (1C) donor 5-methyl tetrahydrofolate and the generation of tetrahydrofolate (THF) in the reaction, engages folate meta

Pathway Diagram:

Ariadne Genomics Inc. 3-sulfinyl pyruvate ---> pyruvate sulfide to sulfate oxidation sulfur dioxide ---> sulfate sulfur dioxide sulfate 3-sulfinyl pyruvate ---> sulfur dioxide pyruvate cysteinesulfinate ---> hypotaurine serine ---> cystathione cystathione ---> alpha-ketobutyrate cystathione ---> ammonium cystathione ---> cysteine Cbs, Cth non-specific reactions 3-sulfinyl pyruvate taurine hypotaurine cysteinesulfinate O2 cysteine hydrogen sulfide alpha-ketobutyrate ammonium cystathione PLP/B6 S-adenosylmethionine serine homocysteine glutathione biosynthesis O2 ---> cysteinesulfinate Cth hypotaurine ---> taurine Csad Cdo1 cysteine ---> hydrogen sulfide cysteine ---> glutathione biosynthesis hydrogen sulfide ---> sulfate cysteinesulfinate ---> 3-sulfinyl pyruvate homocysteine metabolic pathway methionine cycle/metabolic pathway S-adenosylmethionine --+> Cbs Cbs cysteine ---> cysteinesulfinate homocysteine ---> cystathione

Genes in Pathway:

  • Rat
  • Mouse
  • Human
  • All
  • show annotations for term's descendants
  •     Sort by:
  • view all columns
transsulfuration pathway of homocysteine metabolism term browser
Symbol Object Name JBrowse Chr Start Stop Reference
G Cbs cystathionine beta synthase JBrowse link 20 10,361,987 10,386,663 RGD:1359024
G Cdo1 cysteine dioxygenase type 1 JBrowse link 18 40,702,027 40,716,901 RGD:7242427
G Csad cysteine sulfinic acid decarboxylase JBrowse link 7 143,781,520 143,810,880 RGD:7242427
G Cth cystathionine gamma-lyase JBrowse link 2 264,266,959 264,293,040 RGD:1359024

Pathway Gene Annotations

Disease Annotations Associated with Genes in the transsulfuration pathway of homocysteine metabolism
Pathway Annotations Associated with Genes in the transsulfuration pathway of homocysteine metabolism

References Associated with the transsulfuration pathway of homocysteine metabolism:

Ontology Path Diagram:

paths to the root

Import into Pathway Studio: