Screening and metabolic analysis of high-efficiency molluscicidal bacteria based on atmospheric and room temperature plasma mutagenesis

Abstract

Oncomelania hupensis is the only intermediate host of Schistosoma japonicum, highlighting the need for developing low-toxicity, efficient, and economical molluscicides to control schistosomiasis transmission and prevalence. This study screened for effective molluscicides using O. hupensis in an immersion-based biological assay. Bsp dustable powder (DP) emerged as the most effective molluscicide among seven microbial pesticide samples tested. The dominant strain, designated 3–4, was isolated and identified as Bacillus subtilis using 16S rDNA gene sequencing. Following atmospheric and room temperature plasma (ARTP) mutagenesis, a mutant strain library containing 214 strains of bacteria was obtained. Most of the 139 mutant strains showed no significant difference compared with parental strain and 60 strains showed a decrease. Meanwhile, 15 mutant strains with higher molluscicidal effects were obtained. ARTP-129 and ARTP-154, exhibiting the highest positive mutation rates, demonstrated a 64.51 % increase in mortality compared to the parental strain 3–4. Metabolomic analysis revealed that the mutant strains may alter molluscicidal toxicity by regulating the synthesis pathways of metabolites such as l-pyroglutamic acid (PGA). These findings suggest the potential of ARTP mutagenesis for developing novel and effective molluscicides for schistosomiasis control.