Directed evolution of biosynthetic pathways. Recruitment of cysteine thioethers for constructing the cell wall of Escherichia coli.
We report that expansion of thioether biosynthesis in Escherichia coli generates sulfur-containing amino acids that can replace meso-diaminopimelate, the essential amino acid used for cross-linking the cell wall. This was accomplished by jointly overexpressing the metB gene coding for L-cystathionine gamma-synthase and disrupting the metC gene, whose product, L-cystathionine beta-lyase, is responsible for the destruction of L-cystathionine and other L-cysteine thioethers. As a result, meso-lanthionine and L-allo-cystathionine were produced endogenously and incorporated in the peptidoglycan, thereby enabling E. coli strains auxotrophic for diaminopimelate to grow in its absence. Thus, current techniques of metabolic engineering can be applied to evolving the chemical constitution of living cells beyond its present state.
Richaud
C
C
Unité de Physiologie Cellulaire, Centre National de la Recherche Scientifique (CNRS URA 1300), Paris, France.
Mengin-Lecreulx
D
D
Pochet
S
S
Johnson
E J
EJ
Cohen
G N
GN
Marlière
P
P
D000409:Alanine / Q000031:analogs & derivatives / Q000096:biosynthesis / Q000378:metabolism; D000591:Amino Acid Isomerases; D005075:Biological Evolution; D019757:Carbon-Oxygen Lyases; D002473:Cell Wall / Q000378:metabolism*; D003540:Cystathionine / Q000096:biosynthesis / Q000378:metabolism; D003960:Diaminopimelic Acid / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism*; D008190:Lyases / Q000235:genetics; D010457:Peptidoglycan / Q000096:biosynthesis / Q000378:metabolism; D019998:Racemases and Epimerases / Q000378:metabolism; D013440:Sulfides / Q000378:metabolism*
D010457:Peptidoglycan; D013440:Sulfides; D003540:Cystathionine; D003960:Diaminopimelic Acid; C022696:O-succinylhomoserine (thiol)-lyase; D008190:Lyases; D019757:Carbon-Oxygen Lyases; C019965:cystathionine beta-lyase; D019998:Racemases and Epimerases; D000591:Amino Acid Isomerases; C042032:diaminopimelate epimerase; C001520:lanthionine; D000409:Alanine