Differential protein expression by L. sakei CRL1862 during biofilm formationand planktonic culture

PÉREZ IBARRECHE, MARIANA; FADDA S; 1.VIGNOLO G

MAR DEL PLATA

Congreso; SAIB; 2015

Bacteria are able to grow in planktonic (free) or biofilm form.Biofilms are cells bound together by extracellular polymeric substances attached to a surface. In order to characterize the biofilmogenic Lactobacillus sakei CRL1862, was studied the differential pattern of proteins expressed in planktonic and biofilm growth using two-dimensional electrophoresis.Biofilm proteome was obtained by incubation in MRS at 10 °C during 6 days on stainless steel chips and were compared with planktonic proteome obtained under the same conditions.The cells were harvested and 340 µg of proteins were seededin isoelectrofocusingstrips (pH 4-7).Twenty-nine proteins were identified by MALDITOF MS/MS.Tenof them were overexpressed during growth in biofilm while 19 proteins corresponded to planktonic conditions. Proteins involved in the hydrolysis of peptide bonds (acquisition of nutrients), purine synthesis (extracellular matrix compounds), glutamate (peptidoglycan synthesis) and pentoses (present in sessile cells)were overexpressed under biofilm growth. Whereas, in planktonic conditions,enzymes related to energetic pathwayswere mostly expressed. The proteomic approach here applied allowed understand some of the mechanisms and molecular basis used by L. sakei CRL1862 for its adaption to biofilm growth conditions.