title: Evaluating Light-Induced Promoters for the Control of Heterologous Gene Expression in Synechocystis sp. PCC 6803.
abstract: Cyanobacteria are enticing microbial factories, but little is understood how their gene control elements respond to the periodic availability to light. This research tested the capability of PpsbAIIto control gene expression during light/dark conditions when moved to a neutral location within the Synechocystis sp. PCC 6803 genome. When the eYFP reporter gene was run by PpsbAIIin the promoter's native genomic location, mutants exposed to 12-hour light conditions experienced a 15.8× increase in transcript abundance over that observed from the same construct exposed to 12-hour dark conditions. When this same construct was moved to the hypothetical coding region slr0168 in the genome, transcripts generated during 12 hour light conditions accumulated to 1.67X of the levels of transcripts generated by the same construct during 12 hour dark conditions. Three additional promoter constructs, PpsbAIII, PgroEL2, and PsigDwere also tested for differential expression in light and dark conditions within the neutral region slr0168. While low amounts of transcript accumulation were observed from PgroEL2and PsigD, the PpsbAIIIconstruct accumulated 5.79× more transcripts when compared to transcript abundance during dark conditions, which highlights the potential of this promoter to control gene expression during diel-cycle light conditions. Additionally, nucleotide mutations were made to regions within PpsbAII. Mutations to the cis-acting hexo-nucleotide region increased expression 3.71× over that of the native promoter, while the addition of the "HLR" nucleotide region to the PpsbAII::ΔHexconstruct increased expression 2.76× over that of the native promoter. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:45-53, 2017.
authors: Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO, 80523.
authors: Stevan C
authors: SC
authors: Albers
authors: Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO, 80523.|Dept. of Chemical and Biological Engineering, Colorado State University, Fort Collins, CO, 80523.
authors: Christie A M
authors: CA
authors: Peebles
mesh_terms: D015964:Gene Expression Regulation, Bacterial / Q000528:radiation effects; D017930:Genes, Reporter; D008027:Light; D009154:Mutation; D017440:Photoperiod; D010788:Photosynthesis / Q000528:radiation effects; D011401:Promoter Regions, Genetic; D046939:Synechocystis / Q000235:genetics* / Q000254:growth & development / Q000528:radiation effects; D014158:Transcription, Genetic / Q000528:radiation effects*
keywords: cyanobacteria; diel-cycle; heterologous gene expression; light-induced control elements; metabolic engineering