Glycine betaine is a compatible solute, which is able to restore and maintain osmotic balance of living cells. It is synthesized and accumulated in response to abiotic stress. Betaine acts also as a methyl group donor and has a number of important applications including its use as a feed additive. The known biosynthetic pathways of betaine are universal and very well characterized. A number of ...

Antisera were raised in rabbits against ribosomal proteins of Methanobacterium bryantii and used to analyze immunological relationships to ribosomes from other archaebacteria, from eubacteria, and from yeasts. Cross-reaction could be detected within the methanogens and with a member of the extreme halophiles; the degree of immunological similarity reflected the relationship delineated by 16S ri...

Bacteria classified as extreme halophiles, in the genera Halobacterium and Halococcus, contain deoxyribonucleic acid (DNA) which displays two components in a CsCl equilibrium density gradient. The base composition of the major DNA component ranges from 66 to 68% guanine plus cytosine (GC), whereas that of the satellite DNA comprising some 11 to 36% of the total, is between 57 and 60% GC. Purifi...

Information is meager concering the influence of salts on the metabolic processe of halophiles. In fact, reports of the work of Robinson et al. (1952) are the only recent studies in this field. Robinson (1952) showed that there was an optimum concentration of sodium chloride for maximum activity of lactic acid dehydrogenase. While studying the effect of salt on Micrococcwu halodenifns, Robinson...

This section provides an overview of the genetic systems developed in the Archaea. Genetic manipulation is possible in many members of the halophiles, methanogens, Sulfolobus, and Thermococcales. We describe the selection/counterselection principles utilized in each of these groups, which consist of antibiotics and their resistance markers, and auxotrophic host strains and complementary markers...

PERSPECTIVE ................................................................ 222 A Fruitless Search and Its Consequences ................................................................ 222 Three Ideas That Shape Our Concept of Bacterial Evolution .......................................................224 Procaryote-eucaryote dichotomy ..............................................................

The capacity of halophiles to thrive in extreme hypersaline habitats derives partly from the tight regulation of ion homeostasis, the salt-dependent adjustment of plasma membrane fluidity, and the increased capability to manage oxidative stress. Halophilic bacteria, and archaea have been intensively studied, and substantial research has been conducted on halophilic fungi, and the green alga Dun...

Adding acid to brines or mixing acid phosphate with the salt used in preserving fish was recommended by Gibbons (Progr. Rep. Atlantic Fish. Exp. Sta., no. 14, p. 13, 1935), because it was observed that under acid conditions the halophilic bacteria that spoil salted fish cannot grow. The red halophile, Halobacterium cutirubrum, was found to be extremely sensitive to pH changes (Kushner and Bayle...