Open AccessOrganization and regulation of genes for amino acid biosynthesis in lactic acid bacteria
Author(s) -
Chopin Alain
Publication year - 1993
Publication title -
fems microbiology reviews
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.91
H-Index - 212
eISSN - 1574-6976
pISSN - 0168-6445
DOI - 10.1111/j.1574-6976.1993.tb00011.x
Subject(s) - operon , biology , gene , lactococcus lactis , amino acid synthesis , genetics , amino acid , biosynthesis , regulation of gene expression , regulator gene , bacteria , ribosome , structural gene , biochemistry , rna , lactic acid , escherichia coli , lysine
The recent description of large clusters of biosynthetic genes in the chromosome of Lactococcus lactis and, to a lesser extent, of Lactobacillus , has brought some information on gene organization and control of gene expression in these organisms. The genes involved in a given amino acid biosynthetic pathway are clustered at a single chromosomal location and form an operon. Additional genes which are not required for the biosynthesis are present within some operons. Genetic signals are, in general, similar to those found in other prokaryotes. Several systems controlling gene expression have been identified and transcription attenuation seems frequent. Among the attenuation mechanisms identified, one resembles that controlling amino acid biosynthesis in many bacteria by ribosome stalling at codons corresponding to limiting amino acid. The others are different and might be related to a new class of attenuation mechanism. Preliminary evidence for a new type of regulatory mechanism, involving a metabolic shunt, is also reviewed.