Pseudomonas shiyinii ST4 inhibits sexual mating of Sporisorium scitamineum through the GacS/GacA two-component system and the mib1 gene cluster.

Pseudomonas shiyinii ST4 inhibits sexual mating of Sporisorium scitamineum through the GacS/GacA system and the mib1 gene cluster, with mib1 deletion mutants showing reduced activity.

• Why it matters: Sugarcane smut caused by S. scitamineum leads to significant economic losses, and disrupting fungal sexual mating offers a promising biocontrol strategy. Understanding the genetic basis of bacterial inhibition can improve biocontrol approaches.
• What they did: Researchers used transposon mutagenesis, genetic, and bioinformatics analyses to identify the GacS/GacA two-component system, the mib1 gene cluster, and two transcription factors, MibR1 and MibR2, as key regulators of mating inhibitor biosynthesis in strain ST4.
• The result: The study uncovers a genetic regulatory network controlling biocontrol potency, providing clues for identifying anti-mating compounds and advancing biological control methods against sugarcane smut.