Salinity effects on glucose uptake and catabolism in the obligately psychrophilic marine bacterium Vibrio marinus

Studies on the effects of various salinities on the uptake and catabolism of glucose in Vibrio marinus MP-1 revealed several significant shifts in total uptake and respiration as the cells were subjected to increasingly greater concentrations of NaCl. As the salinity increased from 0.30 to 1.0 M NaCl, there was a decrease in the C₆/C₁ (CO₂) ratio. The resulting patterns suggests that the relative participation of the hexose monophosphate pathway in glucose catabolism was altered. This pathway is apparently shut down in the region of the minimum-growth salinity, and may be related to growth limitation at rower salinities. The shift in C₆/C₁ ratio was not affected by changing the incubation temperature, nor was it dependent specifically on the presence of Na⁺ or Cl^-. As the salinity increased from 0.15 to 0.30 M NaCl, there was a shift in the total uptake patterns which suggests the formation and loss of metabolic by-products derived from the first, second, sixth, and presumably fifth carbons of glucose.This paper was taken in part from a dissertation by the senior author, submitted in partial fulfillment of the requirement for the Ph.D. degree, Oregon State University, Corvallis. Published as technical paper No. 3647, Oregon Agricultural Experiment Station.