应用于工程渣土复垦的产γ-PGA菌株的筛选及生物信息学分析OA

Considering the application needs of engineering waste soil reclamation in Pinglu Canal,this study screened a Poly-γ-Glutamic Acid(γ-PGA)-producing strain from naturally fermented soybean paste and con-ducted genomic sequencing and bioinformatics analysis.A γ-PGA-producing strain DDJ22,was isolated and i-dentified as Bacillus sonorensis.Strain DDJ22 exhibited strong nitrogen-fixing and Indole-3-Acetic Acid(IAA)-producing capabilities but weak phosphorus solubilization.Strain DDJ22 produced 21.35 g/L of γ-PGA after 48 h of shake flask fermentation at 37℃and 220 r/min.The genome of strain DDJ22 had a full length of 4 572 542 bp,with the GC content of 45.54%.The genome was rich in carbohydrate metabolism pathways,along with abundant carbohydrate-active enzyme genes and NRPS gene clusters.Cluster1,Clus-ter5,Cluster10,and Cluster16 showed high similarity to known gene clusters of bacillopaline,bacitracin,ba-cillibactin,and amyloliquecidin GF610,respectively.Additionally,strain DDJ22 possessed resistance genes a-gainst livestock pathogens(e.g.,cattle,sheep,and pig pathogens)and heavy metals(e.g.,zinc,copper,mer-cury,cadmium,lead,chromium,and arsenic),effectively inhibiting the growth of Escherichia coli MG1655.It could tolerate copper with the concentrations below 1 000 mg/L,rapidly grow at copper concentrations below 400 mg/L,and withstand zinc concentrations below 500 mg/L.Strain DDJ22 demonstrated excellent plant growth-promoting functions,robust carbohydrate metabolic activity,and antagonistic effects against E.coli as well as copper and zinc,serving as a promising candidate for engineering waste soil reclamation in the Pinglu Canal.