TITLE:
Effect of cra gene mutation on the metabolism of Escherichia coli for a mixture of multiple carbon sources
AUTHORS:
Ruilian Yao, Hiroyuki Kurata, Kazuyuki Shimizu
KEYWORDS:
Escherichia coli; cra Mutant; Catabolite Regulation
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.4 No.3A,
March
29,
2013
ABSTRACT: The major player
for catabolite repression is the phosphotransferase systems (PTSs) and cAMP-Crp. Moreover, Cra controls
the carbon flow in the metabolic network. In the present research, the effect
of modulating cra gene (Δcra) on the consumption of multiple
carbon sources such as glucose and fructose (as well as xylose) was
investigated under both aerobic and anaerobic conditions. It was shown that glucose
and fructose could be co-metabolized with fructose consumed faster than glucose
in cra mutant under both aerobic and
anaerobic conditions. It was also implied that cra mutant consumed higher amount of total carbon sources, which
contributed to the highest metabolite production as compared to the wild type
strain. Thus, cra mutant can be a
good candidate for the efficient utilization
of multiple carbon sources such as glucose and fructose, where xylose
consumption was repressed by catabolite repression. The overall regulation
mechanisms were clarified based on fermentation data and gene transcript
analysis.