Adaptation of anammox bacteria to low temperature via gradual acclimation and cold shocks

Adaptation of anammox bacteria to low temperature via gradual acclimation and cold shocks: Distinctions in protein expression, membrane composition and activities

Kouba, V. (TU Delft BT/Environmental Biotechnology; University of Chemistry and Technology Prague)
D, Vejmelkova (University of Chemistry and Technology Prague)
E, Zwolsman (Student TU Delft)
K, Hurkova (University of Chemistry and Technology Prague)
K, Navratilova (University of Chemistry and Technology Prague)
M, Laureni (Student TU Delft)
Pabst, Martin (TU Delft BT/Environmental Biotechnology)
van Loosdrecht, Mark C.M. (TU Delft BT/Environmental Biotechnology)
Weissbrodt, D.G. (TU Delft BT/Environmental Biotechnology)

2022

Anammox bacteria enable efficient removal of nitrogen from sewage in processes involving partial nitritation and anammox (PN/A) or nitrification, partial denitrification, and anammox (N-PdN/A). In mild climates, anammox bacteria must be adapted to ≤15 °C, typically by gradual temperature decrease; however, this takes months or years. To reduce the time necessary for the adaptation, an unconventional method of ‘cold shocks’ is promising, involving hours-long exposure of anammox biomass to extremely low temperatures. We compared the efficacies of gradual temperature decrease and cold shocks to increase the metabolic activity of anammox (fed batch reactor, planktonic “Ca. Kuenenia”). We assessed the cold shock mechanism on the level of protein expression (quantitative shot-gun proteomics, LC–HRMS/MS) and the structure of membrane lipids (UPLC–HRMS/MS). The shocked culture was more active (0.66±0.06 vs 0.48±0.06 kg-N/kg-VSS/d) and maintained the relative content of N-respiration proteins at levels consistent levels with the initial state, whereas the content of these proteins decreased in gradually acclimated culture. Cold shocks also induced a more efficient expression of potential cold shock proteins (e.g. ppiD, UspA, pqqC), while putative cold shock proteins CspB and TypA were upregulated in both cultures. Ladderane lipids characteristic for anammox evolved to a similar end-point in both cultures; this confirms their role in anammox bacteria adaptation to cold and indicates a three-pronged adaptation mechanism (ladderane alkyl length, introduction of shorter non-ladderane alkyls, polar headgroup). Overall, we show the outstanding potential of cold shocks for low-temperature adaptation of anammox bacteria and provide yet unreported detailed mechanisms of anammox adaptation to low temperatures.

Adaptation
Anammox
Cold shock
Gradually decreasing temperature
Kuenenia
Main stream of municipal sewage

http://resolver.tudelft.nl/uuid:c0a9bd67-a505-440a-9a61-7c98ce931bcd

https://doi.org/10.1016/j.watres.2021.117822

0043-1354

Water Research, 209

Institutional Repository

journal article

© 2022 V. Kouba, Vejmelkova D, Zwolsman E, Hurkova K, Navratilova K, Laureni M, Martin Pabst, Mark C.M. van Loosdrecht, D.G. Weissbrodt