(2R)-phospho-3-sulpholactate synthase, ComA (IPR003830)

Short name: ComA_synth

Overlapping homologous superfamilies

Family relationships


Methanogenic archaea produce methane via the anaerobic reduction of acetate or single carbon compounds [PMID: 12440773]. Coenzyme M (CoM; 2-mercaptoethanesulphonic acid) serves as the terminal methyl carrier for this process. Previously thought to be unique to methanogenic archaea, CoM has also been found in methylotrophic bacteria.

Biosynthesis of CoM begins with the Michael addition of sulphite to phosphoenolpyruvate, forming 2-phospho-3-sulpholactate (PSL). This reaction is catalyzed by members of this family, PSL synthase (ComA) [PMID: 11830598]. Subsequently, PSL is dephosphorylated by phosphosulpholactate phosphatase (ComB) to form 3-sulpholactate [PMID: 11589710], which is then converted to 3-sulphopyruvate by L-sulpholactate dehydrogenase (ComC; EC: [PMID: 10850983]. Sulphopyruvate decarboxylase (ComDE; EC: converts 3-sulphopyruvate to sulphoacetaldehyde [PMID: 10940029]. Reductive thiolation of sulphoacetaldehyde is the final step.

This entry also includes some proteins from plants and fungi, such as HEAT-STRESS-ASSOCIATED 32 from Arabidopsis [PMID: 23439916].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.