Translational system of the hydrogen-oxidizing bacterium Alcaligenes eutrophus

Some structural and functional properties of ribosomes from the hydrogen-oxidizing bacterium Alcaligenes eutrophus were studied in order to investigate the background of expression of genetic information at the translational level. Ribosomal proteins from 30S subunits of A. eutrophus H16 were separated by two-dimensional gel electrophoresis into 21 spots, those from 50S subunits into 32 spots. While electrophoretic mobilities of several ribosomal proteins differed markedly from those of Escherichia coli, proteins sharing common immunological determinants with E. coli ribosomal proteins S1 and L7/L12 were found in A. eutrophus. Shifting from heterotrophic to autotrophic conditions of growth had no influence on the ribosomal protein pattern. Ribosomes of A. eutrophus had similar requirements for Mg²⁺ and poly(U) concentrations for optimum polyphenylalanine synthesis as those of E. coli. Protein synthesis elongation factors Tu from A. eutrophus and E. coli were immunologically similar. Efficiency of the A. eutrophus polyphenylalanine-synthesizing system was comparable to that of an analogous system derived from E. coli. This suggests that A. eutrophus could be employed for efficient expression of recombinant DNA.