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B6db families:
Description Threonine ammonia-lyase.
Notes Rather compact family, built around the validated sequences from bacteria and plants.
Bacteria often possess two isozymes, one biosynthetic (relatively long sequence) and the other biodegradative (shorter sequence).
The validated archaeal enzyme (from Pyrobaculum) has been termed a racemase, but is in fact a promiscuous catalyst, carrying out both the deamination of L-Ser and L-Thr and, less efficiently, the racemization of the same amino acids.

Animals can degrade threonine using serine deaminases (EC, which are phylogenetically close to threonine deaminases.

PDB 2GN1;2GN2;
PLP Fold Type II
PLP-dependent Domain
Domain alignment
Domain hmm
Fold type II

Number of sequences
Sequences in seed alignment
ArchaeaYP_920018 (Thermofilum pendens); YP_001540767 (Caldivirga maquilingensis); YP_001736957 (Candidatus Korarchaeum cryptofilum OPF8); YP_930546 (Pyrobaculum islandicum);
BacteriaTHD1_CORGL (Corynebacterium glutamicum); ZP_00117909 (Cytophaga hutchinsonii); NP_939921 (Corynebacterium diphtheriae); THD2_SALTY (Salmonella typhimurium); ZP_00102817 (Desulfitobacterium hafniense); THD1_MYCTU (Mycobacterium tuberculosis); THD1_HAEIN (Haemophilus influenzae); NP_720699 (Streptococcus mutans); THD2_ECOLI (Escherichia coli); THD1_BACSU (Bacillus subtilis); CAD78318 (Pirellula sp.); THD1_BURCE (Burkholderia cepacia); AAD35443 (Thermotoga maritima); NP_951545 (Geobacter sulfurreducens); CAE09296 (Wolinella succinogenes); THD1_ECOLI (Escherichia coli); AAQ60761 (Chromobacterium violaceum); NP_273919 (Neisseria meningitidis); NP_832162 (Bacillus cereus); THD1_LACLA (Lactococcus lactis (subsp. lactis)); NP_372585 (Staphylococcus aureus); THD1_SALTY (Salmonella typhimurium);
FungiTHDH_ARXAD (Arxula adeninivorans); AAS51458 (Eremothecium gossypii); EAK92244 (Candida albicans); EAA59095 (Aspergillus nidulans); THDH_YEAST (Saccharomyces cerevisiae);
Other_EukaryaXP_004184395 (Entamoeba invadens IP1); BAH84766 (Entamoeba histolytica);
ViridiplantaeTHD1_LYCES (Lycopersicon esculentum); AAG59585 (Nicotiana attenuata); AC090882 (Oryza sativa); THD1_ARATH (Arabidopsis thaliana);

DISPLAY: Fasta format, alignment, hmm, hmm_local

Reference sequence THD2_ECOLI
Domain interval 21-312
Catalytic site 58 K
 Ohnishi M, Saito M, Wakabayashi S, Ishizuka M, Nishimura K, Nagata Y, Kasai S. (2008) Purification and characterization of serine racemase from a hyperthermophilic archaeon, Pyrobaculum islandicum. J Bacteriol 190 1359-65.

 Risso C1, Van Dien SJ, Orloff A, Lovley DR, Coppi MV. (2008) Elucidation of an alternate isoleucine biosynthesis pathway in Geobacter sulfurreducens J Bacteriol 190 2266-74.

 Simanshu DK, Savithri HS, Murthy MR. (2006) Crystal structures of Salmonella typhimurium biodegradative threonine deaminase and its complex with CMP provide structural insights into ligand-induced oligomerization and enzyme activation J Biol Chem 281 39630-41.

 Wessel PM, Graciet E, Douce R, Dumas R. (2000) Evidence for two distinct effector-binding sites in threonine deaminase by site-directed mutagenesis, kinetic, and binding experiments Biochemistry 39 15136-43.

 Wartmann, T.; Rosel, H.; Kunze, I.; Bode, R.; Kunze, G. (1998) AILV1 gene from the yeast Arxula adeninivorans LS3--a new selective transformation marker Yeast 14 1017-25.

 Bornaes, C.; Petersen, J.G.; Holmberg, S. (1992) Serine and threonine catabolism in Saccharomyces cerevisiae: the CHA1 polypeptide is homologous with other serine and threonine dehydratases Genetics 131 531-9.

 Mockel, B.; Eggeling, L.; Sahm, H. (1992) Functional and structural analyses of threonine dehydratase from Corynebacterium glutamicum J Bacteriol 174 8065-72.

 Samach, A.; Hareven, D.; Gutfinger, T.; Ken-Dror, S.; Lifschitz, E. (1991) Biosynthetic threonine deaminase gene of tomato: isolation, structure, and upregulation in floral organs Proc Natl Acad Sci U S A 88 2678-82.

 Datta, P.;Goss, T.J.; Omnaas J.R.; Patil, R.V. (1987) Covalent structure of biodegradative threonine dehydratase of Escherichia coli: homology with other dehydratases Proc Natl Acad Sci U S A 84 393-7.

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last changed 2009/07/15 13:32

B6db families