Structural genes of glutamate 1-semialdehyde aminotransferase for porphyrin synthesis in a cyanobacterium and Escherichia coli

Mol Gen Genet. 1991 Jan;225(1):1-10. doi: 10.1007/BF00282635.

Abstract

In bacteria 5-aminolevulinate, the universal precursor in the biosynthesis of the porphyrin nucleus of hemes, chlorophylls and bilins is synthesised by two different pathways: in non-sulphur purple bacteria (Rhodobacter) or Rhizobium 5-aminolevulinate synthase condenses glycine and succinyl-CoA into 5-aminolevulinate as is the case in mammalian cells and yeast. In cyanobacteria, green and purple sulphur bacteria, as in chloroplasts of higher plants and algae a three step pathway converts glutamate into 5-aminolevulinate. The last step is the conversion of glutamate 1-semialdehyde into 5-aminolevulinate. Using a cDNA clone encoding glutamate 1-semialdehyde aminotransferase from barley, genes for this enzyme were cloned from Synechococcus PCC6301 and Escherichia coli and sequenced. The popC gene of E. coli, previously considered to encode 5-aminolevulinate synthase, appears to be a structural gene for glutamate 1-semialdehyde aminotransferase. Domains with identical amino acid sequences comprise 48% of the primary structure of the barley, cyanobacterial and putative E. coli glutamate 1-semialdehyde aminotransferases. The cyanobacterial and barley enzymes share 72% identical residues. The peptide containing a likely pyridoxamine phosphate binding lysine is conserved in all three protein sequences.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Blotting, Southern
  • Cyanobacteria / enzymology
  • Cyanobacteria / genetics*
  • Escherichia coli / enzymology
  • Escherichia coli / genetics*
  • Genes, Bacterial*
  • Hordeum / enzymology
  • Hordeum / genetics
  • Intramolecular Transferases*
  • Isomerases / genetics*
  • Isomerases / metabolism
  • Molecular Sequence Data
  • Open Reading Frames
  • Porphyrins / biosynthesis*
  • Sequence Homology, Nucleic Acid

Substances

  • Porphyrins
  • Isomerases
  • Intramolecular Transferases
  • glutamate-1-semialdehyde 2,1-aminomutase

Associated data

  • GENBANK/M64566
  • GENBANK/S63796
  • GENBANK/S63798
  • GENBANK/S79268
  • GENBANK/S79270
  • GENBANK/S79277
  • GENBANK/S85222
  • GENBANK/S85224
  • GENBANK/X53695
  • GENBANK/X53696