The influence of medium composition on the microbial secretory production of hydroxyalkanoate oligomers.
J Gen Appl Microbiol
; 67(4): 134-141, 2021 Oct 22.
Article
en En
| MEDLINE
| ID: mdl-33952784
ABSTRACT
With the aid of a chain transfer (CT) reaction, hydroxyalkanoate (HA) oligomers can be secreted by recombinant Escherichia coli carrying the gene encoding a lactate-polymerizing enzyme (PhaC1PsSTQK) in Luria-Bertani (LB) medium supplemented with a carbon source and CT agent. In this study, HA oligomers were produced through microbial secretion using a mineral-based medium instead of LB medium, and the impact of medium composition on HA oligomer secretion was investigated. The focused targets were medium composition and NaCl concentration related to osmotic conditions. It was observed that 4.21 g/L HA oligomer was secreted by recombinant E. coli in LB medium, but the amount secreted in the mineral-based modified R (MR) medium was negligible. However, when the MR medium was supplemented with 5 g/L yeast extract, 3.75 g/L HA oligomer was secreted. This can be accounted for by the enhanced expression and activity of PhaC1PsSTQK upon supplementation with growth-activated nutrients as supplementation with yeast extract also promoted cell growth and intracellular growth-associated polymer accumulation. Furthermore, upon adding 10 g/L NaCl to the yeast extract-supplemented MR medium, HA oligomer secretion increased to 6.86 g/L, implying that NaCl-induced osmotic pressure promotes HA oligomer secretion. These findings may facilitate the secretory production of HA oligomers using an inexpensive medium.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Medios de Cultivo
/
Escherichia coli
/
Polihidroxialcanoatos
/
Polimerizacion
Idioma:
En
Revista:
J Gen Appl Microbiol
Año:
2021
Tipo del documento:
Article