Aminopyrimidine aminohydrolase explained

Aminopyrimidine aminohydrolase
Ec Number:	3.5.99.2
Cas Number:	9024-80-0

Aminopyrimidine aminohydrolase (thiaminase, thiaminase II, tenA (gene)) is an enzyme with systematic name 4-amino-5-aminomethyl-2-methylpyrimidine aminohydrolase.^{[1] [2] [3] [4] [5] [6] [7]} This enzyme catalyses the following chemical reaction

(1) 4-amino-5-aminomethyl-2-methylpyrimidine + H₂O

\rightleftharpoons 4-amino-5-hydroxymethyl-2-methylpyrimidine + ammonia

(2) thiamine + H₂O

\rightleftharpoons 4-amino-5-hydroxymethyl-2-methylpyrimidine + 5-(2-hydroxyethyl)-4-methylthiazole

This enzyme was previously known as thiaminase II.

Notes and References

1. Fujita A, Nose Y . The second type of bacterial thiaminase . The Journal of Vitaminology . 1 . 1 . 1–7 . July 1954 . 13243520 . 10.5925/jnsv1954.1.1 . free .
2. Purification of thiaminase II . Ikehata H . J. Gen. Appl. Microbiol. . 1960 . 6 . 30–39 . 10.2323/jgam.6.30. free .
3. Toms AV, Haas AL, Park JH, Begley TP, Ealick SE . Structural characterization of the regulatory proteins TenA and TenI from Bacillus subtilis and identification of TenA as a thiaminase II . Biochemistry . 44 . 7 . 2319–29 . February 2005 . 15709744 . 10.1021/bi0478648 .
4. Benach J, Edstrom WC, Lee I, Das K, Cooper B, Xiao R, Liu J, Rost B, Acton TB, Montelione GT, Hunt JF . The 2.35 A structure of the TenA homolog from Pyrococcus furiosus supports an enzymatic function in thiamine metabolism . Acta Crystallographica Section D . 61 . Pt 5 . 589–98 . May 2005 . 15858269 . 10.1107/S0907444905005147 .
5. Jenkins AH, Schyns G, Potot S, Sun G, Begley TP . A new thiamin salvage pathway . Nature Chemical Biology . 3 . 8 . 492–7 . August 2007 . 17618314 . 10.1038/nchembio.2007.13 .
6. Jenkins AL, Zhang Y, Ealick SE, Begley TP . Mutagenesis studies on TenA: a thiamin salvage enzyme from Bacillus subtilis . Bioorganic Chemistry . 36 . 1 . 29–32 . February 2008 . 18054064 . 2293645 . 10.1016/j.bioorg.2007.10.005 .
7. French JB, Begley TP, Ealick SE . Structure of trifunctional THI20 from yeast . Acta Crystallographica Section D . 67 . Pt 9 . 784–91 . September 2011 . 21904031 . 3169313 . 10.1107/S0907444911024814 .