Genetic manipulation of native Bacillus cereus : a biotechnological tool for aquaculture

Abstract

This work aimed to perform the genetic manipulation of the native B. cereus #25 strain and to evaluate the colonization in the intestinal tract of Litopenaeus vannamei. The expression of the GFPmut1, absence of amylase activity, and growth in spectinomycin plates confirmed the transformation of the strain (BC25GM). In the shrimp bioassay, its addiction in the feed showed non-difference for water quality, growth performance, and toxic effects for L. vannamei (survival 100%). The presence of cells expressing GFPmut1 in the midgut of the animals was observed, suggesting that the genetically engineered strain colonized the shrimp intestines. The relative fluorescence was 35% higher in the midgut of the shrimps feed with BC25GM. In conclusion, the present work showed that it is possible to manipulate a native B. cereus strain with the nonspecific pSG1154 plasmid. We reported the possibility to implement native strains as a biotechnology tool applied in aquaculture, especially to deliver beneficial molecules for shrimps.