Nutrition and Metabolism of Marine Bacteria XV. Relation of Na + -Activated Transport to the Na + Requirement of a Marine Pseudomonad for Growth

Drapeau, Gabriel R., (McGill University, Montreal, Quebec, Canada),Tibor I. Matula, and Robert A. MacLeod . Nutrition and metabolism of marine bacteria. XV. Relation of Na+ -activated transport to the Na+ requirement of a marine pseudomonad for growth. J. Bacteriol.92: 63–71. 1966.—A marine pseudomonad was found to require 50 to 100 mm Na+ for maximal rate of oxidation ofd -galactose and for the transport ofd -fucose-H 3 into the cells. The same organism required 150 to 200 mm Na+ for the oxidation ofl -alanine and for the transport of φ-aminoisobutyric acid-C 14 (AIB-C 14 ) into the cells. Competition studies indicated thatd -galactose andd -fucose on the one hand andl -alanine and AIB on the other shared common carriers for transporting the compounds into the cells. This parallelism in Na+ response for oxidation and transport extended to growth whenl -alanine was the sole carbon source in the medium. Whend -galactose was the sole carbon source, an amount of Na+ equal to that withl -alanine was needed. KCN and dinitrophenol but not ouabain inhibited the uptake of AIB-C 14 by the cells. K+ in addition to Na+ was required for transport, and both Mg++ and either Cl− or Br− were stimulatory.Photobacterium fischeri was also found to require Na+ specifically for the uptake of AIB-C 14 by the cells.