Osmotic control of luminescence and growth in Photobacterium leiognathi from ponyfish light organs.
Osmolarity was found to control the luminescence and growth of Photobacterium leiognathi strain LN-1a isolated from the light organ of the ponyfish Leiognathus nuchalis (family Leiognathidae). Low osmolarity (ca. 400 mOsm) stimulated luminescence per cell 80 to 100-fold to a level (ca. 2.0 X 10(4) quanta . s-1 . cell-1) equal to that of bacteria taken directly from the light organ and increased the level of luciferase per cell 8 to 10-fold compared to high osmolarity (ca. 800 mOsm). Conversely, high osmolarity stimulated oxygen uptake and growth rate 2 to 4-fold compared to low osmolarity. Of 21 additional tested strains of P. leiognathi from light organs of 9 other ponyfish species, all responded similarly. Low osmolarity may be a host control factor that functions to stimulate the luminescence and restrict the growth of ponyfish light organ bacteria in situ.
D000818:Animals; D005399:Fishes / Q000382:microbiology*; D008156:Luciferases / Q000378:metabolism; D008163:Luminescent Measurements; D010776:Photobacterium / Q000201:enzymology / Q000254:growth & development / Q000502:physiology*; D013559:Symbiosis; D014882:Water-Electrolyte Balance
D008156:Luciferases