Expanding the synthetic biology repertoire of a fast-growing
cyanobacterium Synechococcus elongatus PCC 11801
Abstract
Synechococcus elongatus PCC 11801 is a fast-growing
cyanobacterium, exhibiting high tolerance to environmental stresses. We
have earlier characterized its genome and analysed its transcriptome and
proteome. However, to deploy it as a potential cell factory, it is
necessary to expand its synthetic biology toolbox, including promoter
elements and ribosome binding sites (RBSs). Here, based on the global
transcriptome analysis, 48 native promoters of the genes with high
transcript count were characterized using a fluorescent reporter system.
P cpcB, P psbA1, P
11770 promoters exhibited consistently higher
fluorescence under all the cultivation conditions. Similarly, from the
genome data and proteome analysis, 534 operons were identified. Fifteen
intergenic regions exhibiting higher protein expression from the
downstream gene were systematically characterized for RBSs, using an
operon construct comprising of fluorescent protein genes eyfp and
mTurq under P cpcB (P
cpcB: eyfp:RBS: mTurq:T
rrnB). Overall, the work presents promoter and
RBS sequence libraries, with varying strengths, to expedite
bioengineering of PCC 11801.