Protein extraction from intact cells as a tool in the identification of bifidobadteria
Adam Waśko, Magdalena Polak-Berecka, Michał Kalita Pol J Microbiol 2012; 61 (4): ICID: 1031332 Article type: Original article IC™ Value: 10.00
Abstract provided by Publisher
This study is the first attempt to use proteins isolated from intact cells as markers for identification of bifidobacterial species, such as B. infanis ATCC1567, B. bifidum Bb-12, B. longum KN29, B. catenulatum KD14, and B. animalis BI30, which cannot be reliably distinguished using molecular methods based on nucleic acid analysis. Three protein extraction methods (with 2 M guanidine hydrochloride, with 8 M urea, and Mattarelli’s method) were markedly different as regards the yield of total protein extracts. Among the methods tested, the method by Mattarelli appeared to be the most suitable for the extraction of cell proteins. This method allowed differentiation among all of the examined bifidobacteria species based on sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) profiles, which was confirmed by a unweighted pair group method with arithmetic average (UPGMA) analysis. Two dimensional electrophoresis separation profiles were compared, and the most characteristic spots were characterized by liquid chromatography-tandem mass spectrometry (LC-MS/MS) as potential protein markers for B. infantis, B. bifidum, B. animalis, B. catenulatum, and B. longum. In this work we propose proteins extracted from intact cells as additional molecular markers for bifidobacteria, together with molecular techniques, which can be used to analyze bacterial protein polymorphism and to distinguish among species.