Uncovering the potential of Bacillus amyloliquefaciens 14C2 against plant- parasitic nematodes

Abstract

Plant-parasitic nematodes (PPN) are major constraints to agriculture worldwide, affecting nearly all cultivated crops. The sustainable control of these PPN is currently focused on biological strategies with low impact on the environmental and human health, such as biological control. The genus Bacillus is one of the most studied bacterial genera expressing antagonistic potential against several important PPN. Their nematicidal effect is usually linked to the production of several toxic molecules (e.g., shingosine produced by B. cereus S2 or secreted proteases of endophytic B. cereus BCM2, both against the PPN Meloidogyne incognita; or other proteases of B. cereus i.24 and Lysobacter capsica i.17 against the root-lesion nematode Pratylenchus penetrans). Previously, we have evaluated the nematicidal potential of endophytic and soil-inhabiting PGPR from genus Bacillus against P. penetrans. In this work, we analysed the complete genome sequence of B. amyloliquefaciens (= B. velezensis) 14C2 in search of potential proteases to be explored as natural nematicides. The genome size of B. amyloliquefaciens 14C2 is 3,528,213 bp with an average of GC content of 46.5% and consists of one chromosome of 3.9 Mbp encoding for 3935 protein-coding and 131 RNA genes. Several serine proteases (C2_GM001392, C2_GM001840, C2_GM001358, C2_GM003264 and C2_GM004060), known to be related with nematicidal effect in other bacteria, have been identified and validated. Moreover, 247 proteins involved in biosynthesis of secondary metabolites pathways, also a source of nematoxic molecules, were identified. The B. amyloliquefaciens 14C2 genome has shown to be a potential source for the development of new biotechnological nematicides.