Literature summary for 4.1.2.48 extracted from

Remesh, S.G.; Ghatge, M.S.; Ahmed, M.H.; Musayev, F.N.; Gandhi, A.; Chowdhury, N.; di Salvo, M.L.; Kellogg, G.E.; Contestabile, R.; Schirch, V.; Safo, M.K.
Molecular basis of E. coli L-threonine aldolase catalytic inactivation at low pH (2015), Biochim. Biophys. Acta, 1854, 278-283 .

Application

Application	Comment	Organism
pharmacology	biotechnological potential for the syntheses of pharmaceutically relevant drug molecules because of the stereospecificity	Escherichia coli

Crystallization (Commentary)

Crystallization (Comment)	Organism
hanging drop vapor diffusion, low-pH crystal structure of the enzyme at 2.1 A resolution, with a noncovalently bound uncleaved L-serine substrate, and a pyridoxal 5'-phosphate cofactor bound as an internal aldimine. This structure contrasts with other Escherichia coli L-threonine aldolase structures obtained at physiological pH that show products or substrates bound as pyridoxal 5'-phosphate-external aldimines. The non-productive binding at low-pH is due to an unusual substrate serine binding orientation in which the alpha-amino group and carboxylate group are in the wrong positions (relative to the active site residues) as a result of protonation of the alpha-amino group of the serine, as well as the active site histidines, His83 and His126. Protonation of these residues prevent the characteristic nucleophilic attack of the alpha-amino group of substrate serine on C4' of pyridoxal 5'-phosphate to form the external aldimine. At low pH the change in charge distribution at the active site can result in substrates binding in a non-productive orientation	Escherichia coli

Crystallization (Comment)

Organism

hanging drop vapor diffusion, low-pH crystal structure of the enzyme at 2.1 A resolution, with a noncovalently bound uncleaved L-serine substrate, and a pyridoxal 5'-phosphate cofactor bound as an internal aldimine. This structure contrasts with other Escherichia coli L-threonine aldolase structures obtained at physiological pH that show products or substrates bound as pyridoxal 5'-phosphate-external aldimines. The non-productive binding at low-pH is due to an unusual substrate serine binding orientation in which the alpha-amino group and carboxylate group are in the wrong positions (relative to the active site residues) as a result of protonation of the alpha-amino group of the serine, as well as the active site histidines, His83 and His126. Protonation of these residues prevent the characteristic nucleophilic attack of the alpha-amino group of substrate serine on C4' of pyridoxal 5'-phosphate to form the external aldimine. At low pH the change in charge distribution at the active site can result in substrates binding in a non-productive orientation

Escherichia coli

Organism

Organism	UniProt	Comment	Textmining
Escherichia coli	-	-	-

Purification (Commentary)

Purification (Comment)	Organism
-	Escherichia coli

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
glycine + acetaldehyde	-	Escherichia coli	L-threonine	-	r
L-threonine	-	Escherichia coli	glycine + acetaldehyde	-	r

Cofactor

Cofactor	Comment	Organism	Structure
pyridoxal 5'-phosphate	dependent on	Escherichia coli

General Information

General Information	Comment	Organism
metabolism	reversible cleavage of L-3-hydroxy-alpha-amino acids to glycine and the corresponding aldehydes	Escherichia coli