Helicase-AID: A novel molecular device for base editing at random genomic loci.

CRISPR-enabled deaminase base editing has become a powerful tool for precisely editing nucleotides on the chromosome. In this study DNA helicases, such as Escherichia coli DnaB, were fused to activation-induced cytidine deaminase (AID) to form enzyme complexes which randomly introduces edited bases throughout the chromosome. DnaB-AID was found to increase 2.

Glycosylase base editors enable C-to-A and C-to-G base changes.

Current base editors (BEs) catalyze only base transitions (C to T and A to G) and cannot produce base transversions. Here we present BEs that cause C-to-A transversions in Escherichia coli and C-to-G transversions in mammalian cells. These glycosylase base editors (GBEs) consist of a Cas9 nickase, a cytidine deaminase and a uracil-DNA glycosylase (Ung).

A programmable CRISPR/Cas9-based phage defense system for Escherichia coli BL21(DE3).

Escherichia coli BL21 is arguably the most popular host for industrial production of proteins, and industrial fermentations are often plagued by phage infections. The CRISPR/Cas system is guided by a gRNA to cleave a specific DNA cassette, which can be developed into a highly efficient programable phage defense system. In this work, we constructed a CRISPR/Cas system targeting multiple positions on the genome of T7 phage and found that the system increased the BL21's defense ability against phage infection.

A novel gene expression system for Ralstonia eutropha based on the T7 promoter.

Background: Ralstonia eutropha (syn. Cupriavidus necator) is a model microorganism for studying metabolism of polyhydroxyalkanoates (PHAs) and a potential chassis for protein expression due to various advantages. Although current plasmid systems of R.