Bio-based succinate from sucrose: High-resolution 13C metabolic flux analysis and metabolic engineering of the rumen bacterium Basfia succiniciproducens.
Metab Eng
; 44: 198-212, 2017 11.
Article
em En
| MEDLINE
| ID: mdl-29037780
ABSTRACT
Succinic acid is a platform chemical of recognized industrial value and accordingly faces a continuous challenge to enable manufacturing from most attractive raw materials. It is mainly produced from glucose, using microbial fermentation. Here, we explore and optimize succinate production from sucrose, a globally applied substrate in biotechnology, using the rumen bacterium Basfia succiniciproducens DD1. As basis of the strain optimization, the yet unknown sucrose metabolism of the microbe was studied, using 13C metabolic flux analyses. When grown in batch culture on sucrose, the bacterium exhibited a high succinate yield of 1molmol-1 and a by-product spectrum, which did not match the expected PTS-mediated sucrose catabolism. This led to the discovery of a fructokinase, involved in sucrose catabolism. The flux approach unraveled that the fructokinase and the fructose PTS both contribute to phosphorylation of the fructose part of sucrose. The contribution of the fructokinase reduces the undesired loss of the succinate precursor PEP into pyruvate and into pyruvate-derived by-products and enables increased succinate production, exclusively via the reductive TCA cycle branch. These findings were used to design superior producers. Mutants, which (i) overexpress the beneficial fructokinase, (II) lack the competing fructose PTS, and (iii) combine both traits, produce significantly more succinate. In a fed-batch process, B. succiniciproducens ΔfruA achieved a titer of 71gL-1 succinate and a yield of 2.5molmol-1 from sucrose.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Rúmen
/
Sacarose
/
Isótopos de Carbono
/
Pasteurellaceae
/
Ácido Succínico
/
Engenharia Metabólica
/
Modelos Biológicos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Metab Eng
Assunto da revista:
ENGENHARIA BIOMEDICA
/
METABOLISMO
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Alemanha