Structural highlights
Function
MAAL_CITAM Involved in the methylaspartate cycle. Catalyzes the formation of the alpha,beta-unsaturated bond by the reversible anti elimination of ammonia from L-threo-beta-methylaspartate (L-threo-(2S,3S)-3-methylaspartate) to give mesaconate (By similarity).
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Methylaspartate ammonia lyase (MAL) catalyzes the magnesium-dependent reversible alpha,beta-elimination of ammonia from L-threo-(2S,3S)-3-methylaspartic acid to mesaconic acid. The 1.3 A MAD crystal structure of the dimeric Citrobacter amalonaticus MAL shows that each subunit comprises two domains, one of which adopts the classical TIM barrel fold, with the active site at the C-terminal end of the barrel. Despite very low sequence similarity, the structure of MAL is closely related to those of representative members of the enolase superfamily, indicating that the mechanism of MAL involves the initial abstraction of a proton alpha to the 3-carboxyl of (2S,3S)-3-methylasparic acid to yield an enolic intermediate. This analysis resolves the conflict that had linked MAL to the histidine and phenylalanine ammonia lyase family of enzymes.
Insights into enzyme evolution revealed by the structure of methylaspartate ammonia lyase.,Levy CW, Buckley PA, Sedelnikova S, Kato Y, Asano Y, Rice DW, Baker PJ Structure. 2002 Jan;10(1):105-13. PMID:11796115[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Levy CW, Buckley PA, Sedelnikova S, Kato Y, Asano Y, Rice DW, Baker PJ. Insights into enzyme evolution revealed by the structure of methylaspartate ammonia lyase. Structure. 2002 Jan;10(1):105-13. PMID:11796115
