HHsearch alignment for GI: 254780414 and conserved domain: cd03131

>cd03131 GATase1_HTS Type 1 glutamine amidotransferase (GATase1)-like domain found in homoserine trans-succinylase (HTS). Type 1 glutamine amidotransferase (GATase1)-like domain found in homoserine trans-succinylase (HTS). HTS, the first enzyme in methionine biosynthesis in Escherichia coli, transfers a succinyl group from succinyl-CoA to homoserine forming succinyl homoserine. It has been suggested that the succinyl group of succinyl-CoA is initially transferred to an enzyme nucleophile before subsequent transfer to homoserine. The catalytic triad typical of GATase1 domains is not conserved in this GATase1-like domain. However, in common with GATase1 domains a reactive cys residue is found in the sharp turn between a beta strand and an alpha helix termed the nucleophile elbow. It has been proposed that this cys is in the active site of the molecule. However, as succinyl has been found bound to a conserved lysine residue, this conserved cys may play a role in dimer formation. HTS acti
Probab=97.43  E-value=0.00076  Score=47.71  Aligned_cols=86  Identities=21%  Similarity=0.264  Sum_probs=60.0

Q ss_pred             CHHHHHHCCCCEEEECCCCCCCCC--CCCCCC-CHHHHH----CCCCEEEECHHHHHHHHHCCC-EEEECCCCCCCEEEE
Q ss_conf             988997239979999853889999--999753-768980----899889977899998997096-999869866103667
Q gi|254780414|r   42 ALDYFKEQNPQAIILSGSPASSLD--IDSPQI-PKEILE----SNIPLLGICYGQQIMCQSLGG-KTKNSQSREFGRAFI  113 (520)
Q Consensus        42 ~~e~i~~~~p~GIILSGGP~SV~d--~~ap~~-~~~I~~----~~iPILGICyG~QlLa~~~GG-~V~~~~~~EyG~~~I  113 (520)
T Consensus        54 ~~~~i~~~~~DglIITGAPve~l~fe~v~YW~El~~i~dwa~~~v~stl~iCWaA~Aal~~~ygI~k~~l~~K~fGVf~h  133 (175)
T cd03131          54 TFDDIRDAKFDGLIVTGAPVEHLPFEQVDYWEELTEILDWAKTHVTSTLFSCWAAMAALYYFYGIKKHQLPEKIFGVFPH  133 (175)
T ss_pred             HHHHHHHCCCCEEEEECCCCCCCCCCCCCCHHHHHHHHHHHHHHCCCEEEEHHHHHHHHHHHHCCCCEECCCCEEEEECC
T ss_conf             49987417776689718998878834387799999999999873663345649999999998399840068734886413


Q ss_pred             EECCCCCCCCCCCC
Q ss_conf             52388622278726
Q gi|254780414|r  114 EIKKNCSLLKGMWE  127 (520)
Q Consensus       114 ~i~~~~~lf~gl~~  127 (520)
T Consensus       134 ~~~~~~pLl~g~~d  147 (175)
T cd03131         134 TILEPHPLLRGLDD  147 (175)
T ss_pred             CCCCCCCCCCCCCC
T ss_conf             46899904067898