Corynebacterium ammoniagenes ATCC 6871 has shown potential for industrial coenzyme A (CoA) production. However, improving CoA yield is crucial, given the limited constitutive promoters available in this strain. In a recent study, 20 putative DNA promoters from genes with high transcription levels and 6 promoters from molecular chaperone genes were identified. Through the use of red fluorescence protein (RFP) as a reporter, a range of promoters with varying activity levels were successfully isolated. Notably, the promoter derived from the upstream sequence of the 50S ribosomal protein L21 (Prpl21) demonstrated the strongest activity among the 26 identified promoters. Overexpressing type III pantothenate kinase from Pseudomonas putida under the control of Prpl21 led to a 4.4-fold increase in CoA yield.
This research presents a method for the rational isolation of promoters with diverse activities and their application in metabolic engineering. By enriching the available promoter toolkit for Corynebacterium ammoniagenes, these findings hold value in metabolic engineering and synthetic biology applications. The study’s outcomes offer the potential to optimize pathways, expand product ranges, and enhance productivity in Corynebacterium ammoniagenes ATCC 6871 for industrial purposes.
Corynebacterium ammoniagenes, a Gram-positive soil bacterium, has strains like ATCC 6871 known for their CoA synthesis capacity. While genomic sequencing has identified key enzymes for redirecting carbon flow, precise regulation of biosynthetic gene expression remains a challenge. The development of transformation protocols and vectors based on cryptic plasmids from related species like C. glutamicum has facilitated genetic manipulation in C. ammoniagenes. Despite progress, available promoters for foreign protein expression in C. ammoniagenes remain limited, with activities often suboptimal.
Efficiently engineering C. ammoniagenes necessitates the screening of endogenous promoters. Previous studies isolated promoters from C. ammoniagenes ATCC 6872, but their universal application in strains like ATCC 6871 has been limited. This underscores the importance of finding effective promoters tailored to specific strains like ATCC 6871, emphasizing the need for new promoter sources.
The study’s approach of isolating promoters from genes with high transcription levels and molecular chaperones provides a promising avenue for enhancing CoA production in C. ammoniagenes. By rationally selecting promoters based on transcription data and activity assessments using RFP as a reporter, the research successfully identified potent promoters like Prpl21. Leveraging such promoters for overexpressing key CoA biosynthetic genes led to significant improvements in CoA yield, underscoring the potential of this strategy for metabolic engineering applications.
Key Takeaways:
– Isolating promoters from C. ammoniagenes ATCC 6871 offers a promising route to enhance CoA synthesis for industrial applications.
– Rational selection of promoters from genes with high transcription levels and molecular chaperones can significantly boost metabolic engineering efforts in C. ammoniagenes.
– The identified Prpl21 promoter stands out for its robust activity, showcasing its potential for driving the overexpression of key genes in CoA biosynthesis pathways.
– By expanding the repertoire of available promoters in C. ammoniagenes, this study paves the way for optimizing metabolic pathways and elevating productivity levels in industrial settings.
Tags: synthetic biology, yeast, upstream, transcriptomics, centrifugation, metabolic engineering, chaperones
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