PATTERNS OF OXIDATIVE ASSIMILATION IN STRAINS OF PSEUDOMONAS AND ACHROMOBACTER

Cytological Distribution of the Products of Oxidative Assimilation in Pseudomonas aeruginosa

Tomlinson, Geraldine A. (University of British Columbia, Vancouver, B.C., Canada), and J. J. R. Campbell. Cytological distribution of the products of oxidative assimilation in Pseudomonas aeruginosa. J. Bacteriol. 90:599-603. 1965.-Washed-cell suspensions of Pseudomonas aeruginosa incorporated C(14) largely into the membrane fractions and cytoplasm during oxidative assimilation of uniformly labeled glucose. The ribonucleic acid (RNA) associated with the membranes and the cytoplasm had very high specific activity in contrast to that of the ribosomes. The protein of each fraction comprised the major portion of the radioactivity of that cytological fraction. The proteins of the cytoplasm constituted the predominant product of assimilation. The low level of activity in the ribosomal RNA and protein suggests that oxidative assimilation is not the replenishment of endogenous reserves. The ribosomal fraction, which contained 19.6% of the protein and 65% of the RNA of the extract, incorporated only 2 to 3% of the radioactivity. In contrast, the membrane fraction contained 15.3% of the protein and 6.6% of the RNA, but incorporated 13 to 14% of the radioactivity.

PATTERNS OF OXIDATIVE ASSIMILATION IN STRAINS OF ACETOBACTER AND AZOTOBACTER

Tomlinson, Geraldine A. (The University of British Columbia, Vancouver, B.C., Canada), and J. J. R. Campbell. Patterns of oxidative assimilation in strains of Acetobacter and Azotobacter. J. Bacteriol. 86:1165-1172. 1963.-Oxidative assimilation of glucose-U-C(14) was studied with washed-cell suspensions of Acetobacter aceti, A. xylinum, Azotobacter vinelandii, and A. agilis. The suggestion that oxidative assimilation is largely the incorporation of endogenously produced ammonia is tenable. A. aceti did not exhibit oxidative assimilation and it did not incorporate ammonia in the presence of glucose, alpha-ketoglutarate, or pyruvate. A. xylinum, A. vinelandii, and A. agilis incorporated C(14) into the nitrogenous fractions of the cell. The level of assimilation into A. xylinum was low due to the accumulation of extracellular cellulose, and the level of assimilation into the Azotobacter was low presumably because of the requirement of energy for nitrogen fixation. The Azotobacter were characterized by the presence of a high level of radioactivity in the cold trichloroacetic acid-soluble pool. None of the organisms accumulated compounds in the supernatant fluid that might be considered pacemakers in glucose oxidation, and this could be a contributing factor in the low level of assimilation.