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 of d-galactose and for the transport of d-fucose-H(3) into the cells. The same organism required 150 to 200 mm Na(+) for the oxidation of l-alanine and for the transport of phi-aminoisobutyric acid-C(14) (AIB-C(14)) into the cells. Competition studies indicated that d-galactose and d-fucose on the one hand and l-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 when l-alanine was the sole carbon source in the medium. When d-galactose was the sole carbon source, an amount of Na(+) equal to that with l-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.