A Highly Efficient 5S rRNA-CRISPR/Cas9 Genome Editing Toolkit in .

is an important industrial producer of cephalosporin C (CPC), and efficient genome editing tools are critical for its exploitation and metabolic engineering. Currently, CRISPR/Cas9 systems for employ heterologous promoters, including P or AfU6p, to drive sgRNA expression. These systems often required additional sgRNA processing elements such as ribozymes or tRNAs, which increased cloning complexity and experimental workload.

Establishing a one-step marker-free CRISPR/Cas9 system for industrial Aspergillus niger using counter-selectable marker Ang-ace2.

Objectives: To develop a one-step, marker-free CRISPR/Cas9 system for highly efficient genome editing in industrial Aspergillus niger, with a short genetic operation cycle.

Results: Firstly, evaluation of different promoters for sgRNA expression revealed tRNA as the most efficient, achieving a remarkable 100% gene editing efficiency. Furthermore, a counter-selectable marker, Ang-ace2, was identified for A.

Effective production of kojic acid in engineered Aspergillus niger.

Background: Kojic acid (KA) is a widely used compound in the cosmetic, medical, and food industries, and is typically produced by Aspergillus oryzae. To meet increasing market demand, it is important to optimize KA production through seeking alternatives that are more economic than current A. oryzae-based methods.