Asparagine synthase (glutamine-hydrolysing) explained

Asparagine synthase (glutamine-hydrolysing)
Ec Number:	6.3.5.4
Cas Number:	37318-72-2
Width:	270

Asparagine synthase (glutamine-hydrolysing) (asparagine synthetase (glutamine-hydrolysing), glutamine-dependent asparagine synthetase, asparagine synthetase B, AS, AS-B) is an enzyme with systematic name L-aspartate:L-glutamine amido-ligase (AMP-forming).^{[1] [2] [3] [4] [5] [6]} This enzyme catalyses the following chemical reaction

ATP + L-aspartate + L-glutamine + H₂O

\rightleftharpoons AMP + diphosphate + L-asparagine + L-glutamate (overall reaction)

(1a) L-glutamine + H₂O

\rightleftharpoons L-glutamate + NH₃

(1b) ATP + L-aspartate + NH₃

\rightleftharpoons AMP + diphosphate + L-asparagine

The enzyme from Escherichia coli has two active sites.

Notes and References

1. Patterson MK, Orr GR . Asparagine biosynthesis by the Novikoff Hepatoma isolation, purification, property, and mechanism studies of the enzyme system . The Journal of Biological Chemistry . 243 . 2 . 376–80 . January 1968 . 4295091 .
2. Boehlein SK, Richards NG, Schuster SM . Glutamine-dependent nitrogen transfer in Escherichia coli asparagine synthetase B. Searching for the catalytic triad . The Journal of Biological Chemistry . 269 . 10 . 7450–7 . March 1994 . 7907328 .
3. Richards NG, Schuster SM . Mechanistic issues in asparagine synthetase catalysis . Advances in Enzymology and Related Areas of Molecular Biology . 72 . 145–98 . 1998 . 9559053 .
4. Larsen TM, Boehlein SK, Schuster SM, Richards NG, Thoden JB, Holden HM, Rayment I . Three-dimensional structure of Escherichia coli asparagine synthetase B: a short journey from substrate to product . Biochemistry . 38 . 49 . 16146–57 . December 1999 . 10587437 . 10.1021/bi9915768 . 10.1.1.453.5998 .
5. Huang X, Holden HM, Raushel FM . Channeling of substrates and intermediates in enzyme-catalyzed reactions . Annual Review of Biochemistry . 70 . 149–80 . 2001 . 11395405 . 10.1146/annurev.biochem.70.1.149 .
6. Tesson AR, Soper TS, Ciustea M, Richards NG . Revisiting the steady state kinetic mechanism of glutamine-dependent asparagine synthetase from Escherichia coli . Archives of Biochemistry and Biophysics . 413 . 1 . 23–31 . May 2003 . 12706338 . 10.1016/s0003-9861(03)00118-8 .