Genetics and predicted enzymology of amino acid biosynthesis in L. helveticus CNRZ 32

Amino acid(s)Gene(s) presentaPredicted productPathwayEssentialb
Ala araT Aromatic aminotransferase (EC
bcaT Branched-chain aminotransferase (EC
ataA-CAminotransferase (EC 2.6.1.-)
Arg argF d*Ornithine carbamoyltransferase (EC
arcC d*Carbamate kinase (EC
arcA d Arginine deiminase (EC
carA Carbamoyl-phosphate synthase A (EC
carB Carbamoyl-phosphate synthase B (EC
odcI Ornithine decarboxylase (EC
odiC Ornithine decarboxylase (EC
Asn, Asp asnA Aspartate-ammonia ligase (EC or Asp
asnB Asparagine synthase (EC
ans Asparaginase (EC
aspC*Aspartic aminotransferase (EC
asd*Aspartate-semialdehyde dehydrogenase (EC
ppc d Phosphoenolpyruvate carboxylase (EC
Glu glnA Glutamate-ammonia ligase (EC
aspC Aspartic aminotransferase (EC
Gln glnA Glutamate-ammonia ligase (EC GluNo
Cys cysK* O-Acetylserine (thiol) lyase (EC
cbl*Cystathionine-beta-lyase (EC
cysE*Serine acetyl-transferase (EC
Met metA*Homoserine-O-succinyl transferase (EC
cysK2 d* O-Acetylserine (thiol) lyase (EC
metE 5-Methyltetrahydropteroyl(Glu3)-homocysteine
    methyltransferase (EC
patC d Cystathionine-gamma-lyase (EC
Lys lysA*Diaminopimelate decarboxylase (EC
dapD*2,3,4,5-Tetrahydropyridine-2,6-dicarboxylate N-succinyltransferase (EC
dapE*Succinyl-diaminopimelate desuccinylase (EC
dapA*Dihydrodipicolinate synthase (EC
dapB*Dihydrodipicolinate reductase (EC
aspC*Aspartic aminotransferase (EC
asd*Aspartate-semialdehyde dehydrogenase (EC
lysC Aspartate kinase (EC
dapF Diaminopimelate epimerase (EC
ataA-CAminotransferase (EC 2.6.1.-)
Ile, Leu, Val bcaT Branched-chain aminotransferase (EC
ilvB Acetolactate synthase (EC
Phe, Tyr, Pro araT Aromatic aminotransferase (EC
aspC Aspartic aminotransferase (EC
Ser glyA Glycine hydroxymethyltransferase (EC
glyK Glycerate kinase (EC
serC*Phosphoserine transaminase (EC
serA*Phosphoglycerate dehydrogenase (EC
ycsE Phosphoserine phosphatase (EC
sdaB d l-Serine ammonia-lyase B (EC
sdaA l-Serine ammonia-lyase A (EC
Gly glyA Glycine hydroxymethyltransferase (EC SerNo
  • a Genes for the same amino acid with a shared symbol (* or †) are adjacent to one another in an operon-like structure in the genome and are listed in predicted order of sequential transcription.

  • b As determined by Christensen and Steele (4).

  • c Pathway completion assumes activity for one or more transamination reactions is provided by the aromatic-chain (araT), aspartic (aspC), or branched-chain (bcaT) aminotransferase or by one of three other predicted amino acid aminotransferases (ataA-C) whose genes were identified in the L. helveticus CNRZ 32 genome.

  • d Probable pseudogene; the product is predicted to lack biological activity.