uncharacterized TenA_C proteins similar to Sulfolobus solfataricus TenA-1 (Sso2206)
This family of TenA proteins belongs to the TenA_C class as it has a conserved active site Cys residue; only one of the double Glu residues identified in the active site of TenA_E from the archaeon Pyrococcus furiosus is conserved in this family. TenA_C proteins (EC 3.5.99.2) catalyze the hydrolysis of the thiamin breakdown product 4-amino-5-amino-methyl-2-methylpyrimidine (amino-HMP) to 4-amino-5-hydroxymethyl-2-methylpyrimidine (HMP) in a thiamin salvage pathway. It has also been suggested that TenA proteins act as transcriptional regulators based on changes in gene-expression patterns when TenA is overexpressed in Bacillus subtilis, however this effect may be indirect. This family includes mostly uncharacterized TenA like proteins such as Sulfolobus solfataricus putative TenA-like thiaminase (Tena-1, Sso2206).
Feature 1: conserved active site residues [active site], 2 residue positions
Conserved feature residue pattern:C E
Evidence:
Comment:these proteins have a conserved active site Cys residue, and one of 2 conserved Glu residues in the active site; the Cys is thought to act as a nucleophile in the thiaminase reaction, the Glu is thought to interact with the substituent at the 5-position of the pyrimidine ring