Gene expression and characterization of Linocin M18 gene in Burkholderia seminalis TC3.4.2R3

Abstract

Burkholderia seminalis TC3.4.2R3 was previously isolated from interior of sugarcane roots and belongs to the complex Burkholderia cepacia (Bcc). Bacteria belonging to this group are being increasingly studied and has gained various biotechnological applications in medicine, industry and agriculture. Genus Burkholderia have great nutritional versatility and great ecological importance not only to promote plant growth and contribute to nitrogen fixation, but also for its ability to protect the plant from diseases caused by other micro-organisms such as fungi and other bacteria. It is possible that the beneficial interaction of Burkholderia seminalis with plants can be explained, among other factors, from the synthesis of bacteriocins such as Linocina M18. This bacteriocin was first isolated from Brevibacterium linens M18 and inhibits the growth of Listeria spp. and other Gram-positive bacteria. In the genome of B. seminalis TC3.4.2R3 was observed a gene that encode a linocin that is linked to a peroxidase (dyp-type). Subsequently, it was reported that peptides of Linocin family might be combined in concatamers forming a structure named encapsulin that can encapsulate other proteins. Therefore, the objective of the present project is to evaluate the expression of these Linocin M18 and peroxidase gene in different conditions (with and without the plant), to observe if the expression of these genes is regulated by the plant or by the source of carbohydrate. For this, the mRNA of B. seminalis TC3.4.2R3 grown under different conditions will be extracted in order to assess the environmental conditions that regulate expression of these genes. Moreover, these two genes will be cloned and expressed in Escherichia coli in order to assess the antimicrobial activity of Linocin as well as its ability to encapsulate the peroxidase.