H2020Индивидуална стипендия2021–2023

DMC-ReaDy · Dormant Microbial Communities Reactivation Dynamics in Lake Sediments

„Хоризонт 2020“ — Действия „Мария Склодовска-Кюри“

Период: 2021-04-01 → 2023-04-28
Финансиране от ЕС: 191 149 €
Участници: 1
Схема: MSCA-IF

Линиите свързват координатора с партньорите.

Накратко на български

Микробите в дълбоките езерни утайки се изследват, за да се види дали могат да се „събудят“ и да растат отново при добавяне на храна. Това помага да се разберат механизмите за оцеляване на микроорганизмите в състояние на дълбок покой.

Този кратък обзор е генериран от изкуствен интелект

Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.

Резултати накратко

Dormant Microbial Communities Reactivation Dynamics in Lake Sediments

In aquatic sediments microorganisms are gradually buried by newly deposited layers and cut off from their main energy source, organic matter from overlying water or adjacent land. Yet, large populations of microorganisms are found in buried sediments, living in a state of strongly reduced metabolic activity. The evolutionary advantages of survival in this dormancy-like state remain unclear and may be related to rare events where buried microorganisms are returned to energy-replete conditions after centuries or millennia of starvation. The aim of this project was to observe if and how fast different sediment-inhabiting microbes are able to reactivate their metabolism and resume growth, and to determine the physiological changes and molecular mechanisms associated with the process. To initiate reactivation of starved microorganisms in a natural setting, deep layers of lake sediment were transplanted to energy-rich surface sediments in diffusion chambers allowing nutrients to enter the chamber while preventing invasion of other microbes. During the six months of experiment no change in cell numbers, size or shape, and gene transcription were detected indicating no return of buried microbes to surface layer activity levels. This result contradicts previous findings from experiments performed in more artificial conditions where the detected reactivation might have stemmed from growth of contaminating surface organisms. It is thus a valuable contribution to the debate about microbial ‘dormancy’ in aquatic sediments and limits and nature of microbial survival in general. Apart from the new insights into microbial ‘dormancy’ in sediments, the project also generated valuable data on changes of microbial metabolism with the progression of burial: from sediment surface to deeper layers and knowledge on metabolic capabilities of many abundant yet uncultured groups of sediment bacteria. This new knowledge further helped to understand how lake trophic status shapes the composition of microbial communities in the deposited sediments.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз

Цел на проекта

In aquatic sediments microorganisms are gradually buried by newly deposited layers and cut off from their main energy source, organic matter from overlying water or adjacent land. Yet, large populations of microorganisms are found in buried sediments, living in a state of strongly reduced metabolic activity. The evolutionary advantages of survival in this dormancy-like state remain unclear and may be related to rare events where buried microorganisms are returned to energy-replete conditions after centuries or millennia of starvation.The aim of this project is to observe how fast different sediment-inhabiting microbes are able to reactivate their metabolism and resume growth, and to determine the physiological changes and molecular mechanisms associated with the process. To initiate reactivation of starved microorganisms in a natural setting, deep layers of lake sediment will be transplanted to energy-rich surface sediments in diffusion chambers allowing nutrients to enter the chamber while preventing invasion of other microbes. Changes in gene expression of individual populations, combined with monitoring of cell size, shape, and biomass production will reveal molecular, physiological, and morphological responses involved in exiting starvation. The hypotheses on preferential substrate utilization and interdependencies between different populations derived from results of this in-situ experiment will be tested in controlled laboratory experiments, where targeted reactivation of selected community members will be triggered by addition of predicted preferred substrate.The uncovered mechanisms of microbial starvation survival and reactivation will have implications for the carbon cycling performed by sediment microbial communities, an essential part of the global cycle of carbon sequestration and remineralization. With dormancy being wide-spread in the microbial world, the results will also be relevant for other areas of microbiology and environmental sciences.

Оригинален текст от CORDIS (на английски).

Участници

EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH · ZuerichКоординаторШвейцария