Proposed title: Life in High-Salinity Environments Chapter no.: ____
Author(s): Aharon Oren (PhD)
Department
of Plant and Environmental SciencesThe
91904
Phone: 972 (2) 6584951
Fax: 972 (2) 6584425
E-mail: aharon.oren@mail.huji.ac.il
Proposed topics
1)
Diversity of hypersaline environments; thalassohaline and athalassohaline
brines.
2) Diversity
of extremely and moderately halophilic microorganisms: Archaea, Bacteria, and
Eukarya.
3)
Polyextremophilic halophiles, combining life at high salt concentrations with
life at high or low pH and high or low temperatures.
4) Modes
of adaptation of microorganisms to life at high salt concentrations:
intracellular concentrations of inorganic ions and organic solutes and
adaptation of cellular macromolecules to high intracellular solute
concentrations.
5)
Functional diversity of microorganisms in high-salt environments: the upper
salt concentration at which different physiological processes occur.
6) Assessment
of the contribution of archaeal and bacterial halophiles to the microbial
activities in hypersaline environments.
7) Culture-dependent
studies of the microbial communities inhabiting high-salinity environments:
growth media and incubation conditions to optimize recovery of culturable
microorganisms.
8) Polar
lipids and carotenoid pigments of extremely halophilic Archaea (family Halobacteriaceae)
and Bacteria (Salinibacter) and their use as biomarkers.
9) Culture-independent,
DNA-based analyses of microbial communities in hypersaline environments.
Chapter
Highlights
The
following concepts will be conveyed in this chapter:
1.
Hypersaline environments are inhabited by diverse communities of halophilic and
halophilic microorganisms belonging to all thee domains of life: Archaea,
Bacteria, and Eukarya.
2.
Adaptation of halophilic microorganisms to life at high salt is based either on
the biosynthesis and/or accumulation of organic osmotic solutes, or on the maintenance
of high intracellular KCl concentrations.
3. Not
all physiological types of microorganisms known from low-salt ecosystems are
known to function at the highest salt concentrations.
4.
Culture-dependent and culture-independent methods developed for conventional
ecosystems can be adapted for use in high salinity environments.
5.
Specific pigments and lipids produced by different groups of halophilic
microorganisms can be used as biomarkers for the characterization of high-salt
ecosystems.
