Dataset Information

A versatile genetic engineering toolkit for E. coli based on CRISPR-prime editing.

ABSTRACT: CRISPR base editing is a powerful method to engineer bacterial genomes. However, it restricts editing to single-nucleotide substitutions. Here, to address this challenge, we adapt a CRISPR-Prime Editing-based, DSB-free, versatile, and single-nucleotide resolution genetic manipulation toolkit for prokaryotes. It can introduce substitutions, deletions, insertions, and the combination thereof, both in plasmids and the chromosome of E. coli with high fidelity. Notably, under optimal conditions, the efficiency of 1-bp deletions reach up to 40%. Moreover, deletions of up to 97 bp and insertions up to 33 bp were successful with the toolkit in E. coli, however, efficiencies dropped sharply with increased fragment sizes. With a second guide RNA, our toolkit can achieve multiplexed editing albeit with low efficiency. Here we report not only a useful addition to the genome engineering arsenal for E. coli, but also a potential basis for the development of similar toolkits for other bacteria.

SUBMITTER: Tong Y

PROVIDER: S-EPMC8410854 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A versatile genetic engineering toolkit for E. coli based on CRISPR-prime editing.

Tong Yaojun Y Jørgensen Tue S TS Whitford Christopher M CM Weber Tilmann T Lee Sang Yup SY

Nature communications 20210901 1

CRISPR base editing is a powerful method to engineer bacterial genomes. However, it restricts editing to single-nucleotide substitutions. Here, to address this challenge, we adapt a CRISPR-Prime Editing-based, DSB-free, versatile, and single-nucleotide resolution genetic manipulation toolkit for prokaryotes. It can introduce substitutions, deletions, insertions, and the combination thereof, both in plasmids and the chromosome of E. coli with high fidelity. Notably, under optimal conditions, the ...[more]

PMID: 34471126

Similar Datasets

Project description:Leptospirosis, caused by pathogenic bacteria from the genus Leptospira, is a global zoonosis responsible for more than one million human cases and 60,000 deaths annually. The disease also affects many domestic animal species. Historically, genetic manipulation of Leptospira has been difficult to perform, resulting in limited knowledge on pathogenic mechanisms of disease and the identification of virulence factors. The application of CRISPR/Cas9 and its variations have helped fill these gaps but the generation of knockout mutants remains challenging because double-strand breaks (DSBs) inflicted by Cas9 nuclease are lethal to Leptospira cells. The novel CRISPR prime editing (PE) strategy is the first precise genome-editing technology that allows deletions, insertions, and base substitutions without introducing DSBs. This revolutionary technique utilizes a nickase Cas9 that cleaves a single strand of DNA, coupled with an engineered reverse transcriptase and a modified single-guide RNA (termed prime editing guide RNA) containing an extended 3' end with the desired edits. We demonstrate the application of CRISPR-PE in both saprophytic and pathogenic Leptospira from multiple species and serovars by introducing deletions or insertions into target DNA with a remarkable precision of just one nucleotide. Additionally, we demonstrate the ability to genetically manipulate Leptospira borgpetersenii, a prevalent pathogenic species of humans, domestic cattle, and wildlife animals. Rapid plasmid loss by mutated strains in liquid culture allows for the generation of knockout strains without selective markers, which can be readily used to elucidate virulence factors and develop optimized bacterin and/or live vaccines against leptospirosis.IMPORTANCELeptospirosis is a geographically widespread bacterial zoonosis. Genetic manipulation of pathogenic Leptospira spp. has been laborious and difficult to perform, limiting our ability to understand how leptospires cause disease. The application of the CRISPR/Cas9 system to Leptospira enhanced our ability to generate knockdown and knockout mutants; however, the latter remains challenging. Here, we demonstrate the application of the CRISPR prime editing technique in Leptospira, allowing the generation of knockout mutants in several pathogenic species, with mutations comprising just a single nucleotide resolution. Notably, we generated a mutant in the Leptospira borgpetersenii background, a prevalent pathogenic species of humans and cattle. Our application of this method opens new avenues for studying pathogenic mechanisms of Leptospira and the identification of virulence factors across multiple species. These methods can also be used to facilitate the generation of marker-less knockout strains for updated and improved bacterin and/or live vaccines.

Project description:CRISPR-Cas systems are transforming precision medicine with engineered probiotics as next-generation diagnostics and therapeutics. To promote human health and treat disease, engineering probiotic bacteria demands maximal versatility to enable non-natural functionalities while minimizing undesired genomic interferences. Here, we present a streamlined prime editing approach tailored for probiotic Escherichia coli Nissle 1917 utilizing only essential genetic modules, including Cas9 nickase from Streptococcus pyogenes, a codon-optimized reverse transcriptase, and a prime editing guide RNA, and an optimized workflow with longer induction. As a result, we achieved all types of prime editing in every individual round of experiments with efficiencies of 25.0%, 52.0%, and 66.7% for DNA deletion, insertion, and substitution, respectively. A comprehensive evaluation of off-target effects revealed a significant reduction in unintended mutations, particularly in comparison to two different base editing methods. Leveraging the prime editing system, we inserted a unique DNA sequence to barcode the edited strain and established an antibiotic-resistance-gene-free platform to enable non-natural functionalities. Our prime editing strategy presents a CRISPR-Cas system that can be readily implemented in any laboratories with the basic CRISPR setups, paving the way for future innovations in engineered probiotics.IMPORTANCEOne ultimate goal of gene editing is to introduce designed DNA variations at specific loci in living organisms with minimal unintended interferences in the genome. Achieving this goal is especially critical for creating engineered probiotics as living diagnostics and therapeutics to promote human health and treat diseases. In this endeavor, we report a customized prime editing system for precision engineering of probiotic Escherichia coli Nissle 1917. With such a system, we developed a barcoding system for tracking engineered strains, and we built an antibiotic-resistance-gene-free platform to enable non-natural functionalities. We provide not only a powerful gene editing approach for probiotic bacteria but also new insights into the advancement of innovative CRISPR-Cas systems.

Dataset Information

A versatile genetic engineering toolkit for E. coli based on CRISPR-prime editing.

Publications

A versatile genetic engineering toolkit for E. coli based on CRISPR-prime editing.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets