A method for the identification of proteins secreted by lactic acid bacteria grown in complex media.
Lactic acid bacteria (LAB) are known for their special nutritional requirements, being usually cultured in complex media to achieve optimal growth. In this paper, a protocol based on trichloroacetic acid precipitation of peptides and proteins is presented. The method has been tested on four probiotic LAB strains grown in De Man Rogosa Sharpe (MRS) broth, a complex medium that is often used for the culture of such bacteria. This protocol allowed the detection of 19 proteins after sodium dodecyl sulfate-polyacrylamide gel electrophoresis, 10 of them being successfully identified by tandem MS. Thereafter, the 10 were found to be secreted or surface associated by bioinformatic means. In conclusion, this work supplies a method for the identification of proteins secreted by LAB, allowing discrimination between the proteins present in the MRS and those produced by probiotic LAB.
Laboratoire de Microbiologie et Biochimie Appliquée, Université de Bordeaux, UMR 5248 CBMN, UBX1-ENITAB, ENITAB, Gradignan, France. b-sanchez@enitab.fr
Borja
B
Sánchez
Sthéphane
S
Chaignepain
Jean-Marie
JM
Schmitter
María C
MC
Urdaci
D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D001431:Bacteriological Techniques / Q000379:methods*; D002611:Cheese / Q000382:microbiology; D011232:Chemical Precipitation; D003470:Culture Media / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D007778:Lactobacillus / Q000145:classification / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D052200:Limosilactobacillus reuteri / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D052201:Lacticaseibacillus rhamnosus / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D013294:Lactococcus lactis / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D019936:Probiotics; D015203:Reproducibility of Results; D012756:Sheep; D014238:Trichloroacetic Acid
D001426:Bacterial Proteins; D003470:Culture Media; D014238:Trichloroacetic Acid