Bacterial growth efficiency on natural dissolved organic matter

Quenching of excited triplet states by dissolved natural organic matter.

Excited triplet states of aromatic ketones and quinones are used as proxies to assess the reactivity of excited triplet states of the dissolved organic matter ((3)DOM*) in natural waters. (3)DOM* are crucial transients in environmental photochemistry responsible for contaminant transformation, production of reactive oxygen species, and potentially photobleaching of DOM. In recent photochemical ...

Modeling bacterial utilization of dissolved organic matter : Optimization replaces Monod growth kinetics

A bioenergetic model has been developed to examine growth kinetics associated with bacterial utilization of dissolved organic matter (DOM), NH4+, and N03-. A set of 11 metabolic reactions are used to govern the incorporation, oxidation, and N remineralization of DOM and dissolved inorganic N associated with bacterial growth. For each reaction, free energies and electron transfer requirements ar...

Limitation of bacterial growth by dissolved organic matter and iron in the Southern ocean.

The importance of resource limitation in controlling bacterial growth in the high-nutrient, low-chlorophyll (HNLC) region of the Southern Ocean was experimentally determined during February and March 1998. Organic- and inorganic-nutrient enrichment experiments were performed between 42 degrees S and 55 degrees S along 141 degrees E. Bacterial abundance, mean cell volume, and [(3)H]thymidine and...

Bacterial release of dissolved organic matter during cell growth and decline: Molecular origin and composition

Heterotrophic bacterial growth and the chemical composition of dissolved organic matter (DOM) produced by bacteria from freshwater and marine environments were monitored during experiments with artificial media containing glucose as the sole carbon source. Glucose was quickly consumed, and DOM was released during bacterial growth. Percentages of extracellular release of DOM from bacteria ranged...

Betaproteobacteria growth and nitrification rates during long-term natural dissolved organic matter decomposition experiments