Submitted to: Society of Industrial Microbiology Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: July 31, 2000
Publication Date: N/A
Technical Abstract: Ruminococcus albus and Ruminococcus flavefaciens are competitors for cellulose in the ruminal fermentation. Inhibition of growth of R. flavefaciens strains FD-1 and B34b by R. albus 7 was observed in both liquid media and on solid media. The inhibitory agent was shown to be heat labile (100C, 15 min) and sensitive to proteases, suggesting that the agent is a bacteriocin. Culture supernatants of R. albus 7 were subjected to ammonium sulfate precipitation (60% saturation) and the pellet was dissolved in buffer, concentrated by ultrafiltration through a 10 kDa membrane, and purified by sequential chormatography through gel filtration (Toyoperal HW55F and HW50F) and anion exchange (DEAE 650M) columns. SDS-PAGE revealed that the active fraction from the final column contained two bands (MW appx. 36 kDa and 45 kDa). The inhibitory activity was contained in the 36 kDa component. The active agent was electroblotted onto a PVDF membrane for N-terminal internal sequencing.