Transcriptional analysis of metabolic and virulence genes associated with biofilm formation in Piscirickettsia salmonis strains. Issue 21 (31st October 2020)

• Record Type: Journal Article
• Authors: Zúñiga, A; Solis, C; Cartes, C; Nourdin, G; Yañez, A; Romero, A; Haussmann, D; Figueroa, J
• Is Part Of: FEMS microbiology letters. Volume 367:Issue 21(2020)
• Publication Date: 2020-10-31
• Subjects: piscirickettsiosis -- biofilm -- biofilm genes -- Piscirickettsia salmonis; Microbiology -- Periodicals; 579
• DOI: 10.1093/femsle/fnaa180
• Languages: English
• ISSNs: 0378-1097

Abstract

ABSTRACT: Piscirickettsia salmonis is a facultative intracellular bacterium that generates piscirickettsiosis affecting salmonids in Chile. The bacterium has the adaptability to survive in the marine environment under multiple stressful conditions. In this sense, this work focused on the analysis of a gene battery associated with biofilm formation under different culture conditions and on the adaptability of this biofilm to different media. The results indicated that the strains LF-89, IBM-034 and IBM-040 were strong biofilm producers, evidencing adaptability to the media by increasing the amount of biofilm through successive growths. Transcript levels of six genes described in various bacteria and P. salmonis, considered to have metabolic functions, and playing a relevant role in biofilm formation, were analyzed to evaluate bacterial functionality in the biofilm. The genes mazE-mazF, implicated in biofilm and stress, were markedly overexpressed in the biofilm condition in the three strains. For its part, gene gltA, an indicator of metabolic activity and related to virulence inhibition in Salmonella typhimurium, also seems to restrain the pathogenesis process in P. salmonis by inhibiting the expression of the virulence-associated genes liso and tcf . Finally, the expression of the glnA gene suggests the use of glutamine as an essential element for the growth of the biofilm. Abstract : This study determined the association between biofilm formation of Piscirickettsia salmonis strains on liquid or solid culture media and examined the expression of genes of the toxin-antitoxin system, metabolism and virulence.