Photoinhibition of marine nitrifying bacteria. I. Wavelength-dependent response

作者：MA Guerrero, RD Jones · 发表于：Marine Ecology Progress Series · 年份：1996 · DOI：10.3354/meps141183 · 被引用次数：179 · 研究领域：Wastewater Treatment and Nitrogen Removal、Microbial Community Ecology and Physiology、Marine and coastal ecosystems

Axenic cultures of chemolithotrophic nitrifying bacteria (NH,' and NOz-oxidizers) respond to light in distinct manners.After short-term (2 to 4 h ) monochromatic irradiations both types of nitrifying bacteria demonstrated a widespread photosensitivity in the near-UV region (300 to 375 nm) and a differential photosensitivity in the blue region of the spectrum (400 to 475 nm).Nitrite oxidizers were less sensitive overall to blue llght inhibition than were ammonium oxidizers.Character-~stically, the extent of the photoinhibition was species-specific and light response was dose-and wavelength-dependent. Photoprotection by higher substrate concentrations was only observed with ammonium oxidizers.Increased cell densities altered the phototolerance of nitrite oxidizers and made these organisms light-susceptible.Similarly, treatment wlth a low light dose for extended periods was more damaging to nitrite oxidizers, when high cell densities were used.Polychromatic irradiations served to confirm the monochromatic results.Cool-white fluorescent light inhibited NH,' oxidizing activity but not NO2oxidizing activity.Exposure to sunlight resulted in inhibition of activity in both types of nitrif ~e r s .These data demonstrate that the effect of light on autotrophic nitrification depends not only on the type of nitrifier (NH,' or N O 2 oxidizer), but also on the conditions of their environment.