title: Effects of magnesium sulfate on the luminescence of Vibrio fischeri under nutrient-starved conditions.
abstract: In this study, we investigated the relationship between MgSO(4) and luminescence in Vibrio fischeri under nutrient-starved conditions. When V. fischeri was cultured in an artificial seawater medium, the luminescence intensity was low relative to that observed under normal growth conditions. It decreased during the initial 14 h, and then increased slightly at 24 h. This regulation of luminescence was not dependent on the quorum-sensing mechanism, because the cell densities had not reached a critical threshold concentration. Under MgSO(4)-starved conditions, luminescence was not fully induced at 14 h, and decreased at 24 h. In contrast, induction of luminescence occurred under MgSO(4)-supplemented conditions, but MgSO(4) alone was insufficient to induce luminescence, and required NaHCO(3) or KCl. These results suggest that the luminescence of V. fischeri is controlled by an exogenous sulfur source under nutrient-starved conditions. In addition, they indicate that the induction of sulfur-dependent luminescence is regulated by the NaHCO(3) or KCl concentration.
authors.affiliation: Faculty of Environment Engineering, The University of Kitakyushu, Fukuoka, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Tabei
authors.forename: Mariko
authors.initials: M
authors.lastname: Era
authors.forename: Akane
authors.initials: A
authors.lastname: Ogawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Morita
mesh_terms: D048908:Aliivibrio fischeri / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D001426:Bacterial Proteins / Q000378:metabolism; D003470:Culture Media; D008027:Light; D049449:Luminescence; D008163:Luminescent Measurements / Q000379:methods; D008278:Magnesium Sulfate / Q000494:pharmacology*; D011189:Potassium Chloride / Q000494:pharmacology; D053038:Quorum Sensing; D015398:Signal Transduction / Q000187:drug effects / Q000528:radiation effects; D017693:Sodium Bicarbonate / Q000494:pharmacology; D013217:Starvation
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D011189:Potassium Chloride; D008278:Magnesium Sulfate; D017693:Sodium Bicarbonate