Cell-free amino acid-incorporating system from Pseudomonas indigofera.

Shiio, Tsuru (Washington State University, Pullman), and Bruce A. McFadden. Cell-free amino acid-incorporating system from Pseudomonas indigofera. J. Bacteriol. 90:978-983. 1965.-A cell-free preparation from Pseudomonas indigofera incorporated C(14)-phenylalanine and C(14)-leucine into a product which was insoluble in hot trichloroacetic acid. The phenylalanine incorporation process, which had a temperature optimum of 30 C and a pH optimum of 7.6, had many characteristics of protein synthesis. The process depended upon both "ribosomes" and supernatant fraction from centrifugation at 105,000 x g. Incorporation required adenosine triphosphate, apparently depended upon guanosine triphosphate, and was inhibited by chloramphenicol, puromycin, actinomycin, ribonuclease, and deoxyribonuclease. Leucine incorporation was also studied and had many similar characteristics. C(14)-phenylalanine uptake was stimulated by sRNA or polyuridylic acid, and together these substances had a synergistic effect upon stimulation. The incorporation of C(14)-phenylalanine into a product which was precipitated by antiserum to crystalline isocitrate lyase was also observed.