>TIGR03351 PhnX-like phosphonatase-like hydrolase. This clade of sequences are the closest homologs to the PhnX enzyme, phosphonoacetaldehyde (Pald) hydrolase (phosphonatase, TIGR01422). This phosphonatase-like enzyme and PhnX itself are members of the haloacid dehalogenase (HAD) superfamily (pfam00702) having a a number of distinctive features that set them apart from typical HAD enzymes. The typical HAD N-terminal motif DxDx(T/V) here is DxAGT and the usual conserved lysine prior to the C-terminal motif is instead an arginine. Also distinctive of phosphonatase, and particular to its bi-catalytic mechanism is a conserved lysine in the variable "cap" domain. This lysine forms a Schiff base with the aldehyde of phosphonoacetaldehyde, providing, through the resulting positive charge, a polarization of the C-P bond necesary for cleavage as well as a route to the initial product of cleavage, an ene-amine. The conservation of these elements in this phosphonatase-like enzyme suggests that the

Probab=95.63  E-value=0.022  Score=35.98  Aligned_cols=34  Identities=12%  Similarity=0.241  Sum_probs=23.3

Q ss_pred             CCEEEEECCCEEEECCCCCCCHHHHHHHHHHCCCCE
Q ss_conf             799999274432318814862799999999879819
Q gi|254780847|r   15 YDVILCDVWGVLHNGQKFLPGTIPALKEARENGLKV   50 (282)
Q Consensus        15 yd~~lfD~DGvL~~g~~~ipgA~e~l~~L~~~g~~~   50 (282)
T Consensus         1 ikaViFD~DGTLvDs~~~~~~a~~--~~~~~~G~~~   34 (220)
T TIGR03351         1 ISLVVLDMAGTTVDEDGLVYRALR--QAVTAAGLSP   34 (220)
T ss_pred             CEEEEEECCCCHHHCHHHHHHHHH--HHHHHCCCCC
T ss_conf             979999387767758999999999--9999878898