Growth rate of a non-fermentative Escherichia coli strain is influenced by NAD+ regeneration.
By complementing a non-fermentative Escherichia coli (ldhA (-) pflB (-)) strain with the recombinant Zymomonas mobilis ethanol pathway (pdc, adhB), we evaluated the effect of different levels of enzymatic activity on growth rate demonstrating that there is a direct relationship between anaerobic growth rate and the total specific activity of pyruvate decarboxylase, which is the limiting enzyme of this specific fermentative NAD(+) regenerating pathway. This relationship was proved to be useful to establish a selection strategy based on growth rate for the analysis of lctE libraries, which encode lactate dehydrogenase from Bacillus subtilis.
Vázquez-Limón
Consuelo
C
Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apartado Postal 510-3, Cuernavaca, Morelos, 62250, Mexico, joel@ibt.unam.mx.
Vega-Badillo
Joel
J
Martínez
Alfredo
A
Espinosa-Molina
Gabriela
G
Gosset
Guillermo
G
Soberón
Xavier
X
López-Munguía
Agustín
A
Osuna
Joel
J
D000693:Anaerobiosis; D015169:Colony Count, Microbial; D019020:Directed Molecular Evolution; D004926:Escherichia coli / Q000166:cytology / Q000254:growth & development*; D005285:Fermentation; D007700:Kinetics; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D016296:Mutagenesis; D050505:Mutant Proteins / Q000378:metabolism; D009243:NAD / Q000378:metabolism*; D011767:Pyruvate Decarboxylase / Q000378:metabolism; D017355:Zymomonas / Q000201:enzymology
D050505:Mutant Proteins; D009243:NAD; D007770:L-Lactate Dehydrogenase; D011767:Pyruvate Decarboxylase