<i>Bacillus subtilis</i> Biosensor Engineered To Assess Meat Spoilage

Abstract

Here, we developed a cell-based biosensor that can assess meat freshness using the Gram-positive model bacterium <i>Bacillus subtilis</i> as a chassis. Using transcriptome analysis, we identified promoters that are specifically activated by volatiles released from spoiled meat. The most strongly activated promoter was P<i>_sboA</i>, which drives expression of the genes required for the bacteriocin subtilosin. Next, we created a novel BioBrick compatible integration plasmid for <i>B. subtilis</i> and cloned P<i>_sboA</i> as a BioBrick in front of the gene encoding the chromoprotein amilGFP inside this vector. We show that the newly identified promoter could efficiently drive fluorescent protein production in <i>B. subtilis</i> in response to spoiled meat and thus can be used as a biosensor to detect meat spoilage