Establishment of CRISPR-Cpf1-assisted gene editing tool and engineering of 4-hydroxyisoleucine biosynthesis in Corynebacterium glutamicum.

Corynebacterium glutamicum, an important industrial producer, is a model microorganism. However, the limited gene editing methods and their defects limit the efficient genome editing of C. glutamicum.

Exploring L-isoleucine riboswitches for enhancing 4-hydroxyisoleucine production in Corynebacterium glutamicum.

Objectives: To explore an L-isoleucine (Ile)-induced biosensor for down-regulation of Ile synthesis pathway and enhancement of 4-hydroxyisoleucine (4-HIL) production in Corynebacterium glutamicum SN01.

Results: Four Ile-induced riboswitches (IleRSN) with different strength were screened from mutation library based on TPP riboswitch. Firstly, IleRSN were integrated into the chromosome of strain SN01 immediately upstream of ilvA gene.

Quorum sensing-mediated dynamic regulation of 4-hydroxyisoleucine biosynthesis in Corynebacterium glutamicum.

With the development of synthetic biology, some quorum sensing (QS) systems have been studied and applied to coordinate growth and production. Recently, a novel ComQXPA-P system with different response strengths was constructed in Corynebacterium glutamicum. However, the plasmid-harbored ComQXPA-P system lacks genetic stability, which restricts the application of this QS system.

Dynamic control of 4-hydroxyisoleucine biosynthesis by multi-biosensor in Corynebacterium glutamicum.

4-hydroxyisoleucine (4-HIL) has a potential value in treating diabetes. The α-ketoglutarate (α-KG)-dependent isoleucine dioxygenase (IDO) can catalyze the hydroxylation of L-isoleucine (Ile) to form 4-HIL by consuming O. In our previous study, the ido gene was overexpressed in an Ile-producing Corynebacterium glutamicum strain to synthesize 4-HIL from glucose.

An ultrasensitive biosensor for dual-specific DNA based on deposition of polyaniline on a self-assembled multi-functional DNA hexahedral-nanostructure.

Kras and Braf are major oncogenes. The mutation of Kras codon 12 or Braf V600E can lead to ovarian carcinoma. The detection of oncogene-related DNAs and their mutations offers solution for early diagnosis of ovarian cancer.