Rupture of nodule bacteria on drying and rehydration

Extraction of soil organic phosphorus

“…In particular, drying can increase the amount of organic phosphorus extracted in water [91] and bicarbonate [101]. Water-extractable organic phosphorus is markedly influenced by even mild drying [91], because rewetting releases compounds from microbial cells that lyse during rapid rehydration [107,108]. A similar mechanism probably occurs following freezing and thawing [109].…”

The Physiological Mechanisms of Desiccation Tolerance in Rhizobia

“…However, as reported in Chapter 4, growing rhizobia and in particular TA1, in peat extract was found to consistently increase desiccation tolerance. Salema et al (1982b) reported that the process of drying and rehydration resulted in the rupture of the TA1 cell envelope causing death. Hence, to be able to withstand the process of drying and rehydration, cells must have a healthy cell envelope in order to remain viable.…”

“…However, it is within the plasma membrane that structural components of the cell envelope are synthesised and assembled (Costerton et al, 1974). Salema et al (1982b) reported on the effects of dessication and rehydration on membrane integrity of Rhizobium trifolii WU1 (TA1). Electron micrographs of TA1 showed that cell membranes ruptured upon rehydration on the subpolar region of the cells where the flagellum emerges, suggesting that this may be a point of weakness in membranes of cells.…”

“…However, cells exposed to desiccation stress fluoresced once rehydrated, suggesting that leakage of intracellular contents occurs upon rehydration. Salema et al (1982b) also reported that the membrane rupture of R. trifolii (TA1) air-dried cells occurred upon rehydration and the loss of intracellular material was the cause of cell death. FIGURE 1.1: Schematic representation of the lipid bilayer as it transitions from a liquidcrystalline phase to a gel phase after the removal of water and from a gel phase to a liquidcrystalline phase upon rehydration.…”

Selenium speciation and bioavailability in Dutch agricultural soils: the role of soil organic matter

“…A large fraction of the increase of DOC concentrations after soil drying has been attributed to microbial cell lysis induced by osmotic shock upon rewetting the dried soils (Salema et al, 1982;Kieft et al, 1987;Zsolnay et al, 1999), which produces hydrophilic (Hy) or non-humic DOM (Zsolnay et al, 1999;Koopmans and Groenenberg, 2011). Koopmans and Groenenberg (2011) and Kieft et al (1987) reported that bacterial biomass may contribute 20 to 62% of the increase of DOC concentrations in their soil samples upon drying.…”