In vitro screening and in silico prediction of antifungal metabolites from rhizobacteriumAchromobacter kerstersiiJKP9

The main objective of this study was to identify the antifungal metabolites fromAchromobacter kerstersiiJKP9, a rhizosphere bacterium isolated from tomato cultivations, inhibiting the melanin biosynthetic pathways in vascular wilt pathogenFusarium oxysporumf. sp.lycopersici(Fol).To achieve this objective, all the rhizobacterial morphotypes were screened for plant-growth-promoting and antagonistic activities. Ethyl acetate extract ofAchromobacter kerstersiiJKP9 was purified in HPLC and predicted for antifungals in GC-MS equipped with Wiley library. After identification, molecular docking of useful ligands with modeled Short-chain Dehydrogenase/ Reductase (SDR) of Fol (Locus: FOXG_00472). Results were indicated that the potential strainAchromobacter kerstersiiJKP9 exclusively secreted five pyrrole analogs notable for their antifungal role with no extracellular antifungal enzyme production as seen in other rhizobacterial isolates. In silico docking studies identified, Pyrrolo[1, 2-a]pyrazine-1,4-dione, hexahydro- as effective for SDR in Fol. From these results, we conclude that bacterial pyrroles can be used as an effective fungicide to controlFusariumwilt in tomatoes. In the future, these pyrrole derivatives can directly be employed as eco-friendly fungicides or may be used as antifungal supplements in agrochemical products for the sustainable production of tomatoes.