Relationship of the internal solute composition to the salt tolerance of Halomonas elongata

1983 ◽  
Vol 29 (4) ◽  
pp. 407-414 ◽  
Author(s):  
Russell H. Vreeland ◽  
Bradley D. Mierau ◽  
Carol D. Litchfield ◽  
Eugene L. Martin
Keyword(s):  
Salt Tolerance ◽  
Glutamic Acid ◽  
Osmotic Pressure ◽  
Growth Medium ◽  
Defined Medium ◽  
Pressure Increase ◽  
Chemically Defined Medium ◽  
Halomonas Elongata ◽  
Relationship Of ◽  
Solute Composition

The recently described genus Halomonas contains bacteria which are extremely tolerant to salt. The basis for this halotolerance was studied in cells grown in a chemically defined medium containing 0.05, 1.37, or 3.4 M NaCl. The organisms increase the intracellular concentration of sodium and calcium as well as glutamic acid and alanine as the concentration of NaCl in the growth medium increases. The data indicate that in high salt concentrations the osmotic pressure increase associated with those internal changes detected in this study does not balance the changes in the external osmotic pressure.

Growth characteristics, effects of temperature, and ion specificity of the halotolerant bacterium Halomonas elongata

1980 ◽  
Vol 26 (7) ◽  
pp. 746-752 ◽  
Author(s):  
R. H. Vreeland ◽  
E. L. Martin
Keyword(s):  
Salt Tolerance ◽  
Growth Medium ◽  
Defined Medium ◽  
Temperature Tolerance ◽  
Growth Characteristics ◽  
Effect Of Temperature ◽  
Defined Media ◽  
Absolute Requirement ◽  
Halomonas Elongata ◽  
Nacl Concentration

The genus Halomonas (type species H. elongata) is a new bacterial genus composed of salt tolerant bacteria. The growth characteristics and morphology of the type strain of this bacterial group were studied using both complex and defined media. The salt tolerance of the bacterium decreased significantly on defined medium, suggesting that the type of growth medium used has a great effect on bacterial salt tolerance. Experiments on the effect of temperature on salt tolerance indicate that a temperature of 30 °C permits the greatest salt tolerance. In all of these experiments 0.375 and 1.37 M NaCl yielded the most rapid growth rates while 1.37 and 2.5 M NaCl permitted the greatest temperature tolerance. The Halomonas strain was found to have an absolute requirement for the Na+ cation. While NaNO3 and NaBr would substitute for NaCl in the growth medium, when LiCl, NH4Cl, MgCl2∙6H2O, or KCl was substituted for NaCl, the medium would not support growth. The bacterium consistently retained its rod shape regardless of the NaCl concentration in both complex and defined media. The data indicate that even though this bacterium has been in culture for over 5 years it is still well adapted to life in its natural environment.

STEROL PRODUCTION BY SOME WOOD-ROTTING BASIDIOMYCETES

1965 ◽  
Vol 43 (11) ◽  
pp. 1347-1353 ◽  
Author(s):  
Francis H. Milazzo
Keyword(s):  
Growth Medium ◽  
Organic Nitrogen ◽  
Inorganic Nitrogen ◽  
Defined Medium ◽  
Chemically Defined Medium ◽  
Active Growth

Fourteen species (six genera) of wood-rotting basidiomycetes cultured in a chemically defined medium were examined for the presence of sterol material. These fungi were found to contain ergosterol in amounts that ranged in value from 0.017 to 0.42% of their mycelial dry weights. Such values are, in general, comparable to sterol values reported for other fungi.The synthesis of sterol by Fomes meliae was found to accompany active growth of the fungus and was quantitatively influenced by the composition of the growth medium. Hexose supported greater production of sterol than did pentose, and organic nitrogen was superior to inorganic nitrogen in respect to this synthesis. The combination of hexose and organic nitrogen supported the greatest synthesis of sterol.

scholarly journals Growth Medium-Dependent Regulation ofMyxococcus xanthus Fatty Acid Content Is Controlled by theesg Locus

1998 ◽  
Vol 180 (19) ◽  
pp. 5269-5272 ◽  
Author(s):  
Geoffrey Bartholomeusz ◽  
Yanglong Zhu ◽  
John Downard
Keyword(s):  
Fatty Acid ◽  
Growth Medium ◽  
Acid Content ◽  
Fatty Acid Biosynthesis ◽  
Fatty Acid Content ◽  
Defined Medium ◽  
Chain Fatty Acid ◽  
Complex Medium ◽  
Chemically Defined Medium ◽  
Branched Chain

ABSTRACT We compared the cellular fatty acid profiles of Myxococcus xanthus cells grown in either a Casitone-based complex medium or a chemically defined medium. The cells grown in the complex medium had a much higher content of the abundant branched-chain fatty acidiso-15:0 and several other branched-chain species. The higher branched-chain fatty acid content of the cells grown in the complex medium was dependent on the esg locus, which encodes the E1α and E1β components of a branched-chain keto acid dehydrogenase (BCKAD) multienzyme complex involved in branched-chain fatty acid biosynthesis. Cells grown in the complex medium were also found to have a higher level of esg transcription and more BCKAD enzyme activity than cells from the chemically defined medium. The level of esg transcription appears to be an important factor in the growth medium-dependent regulation of the M. xanthus branched-chain fatty acid content.

Some factors influencing vitamin B12 production by Pseudomonas denitrificans

1970 ◽  
Vol 16 (9) ◽  
pp. 809-815 ◽  
Author(s):  
Horace J. Daniels
Keyword(s):  
Oxalic Acid ◽  
Glutamic Acid ◽  
Aminolevulinic Acid ◽  
Defined Medium ◽  
Vitamin B ◽  
Chemically Defined Medium ◽  
Mineral Salts ◽  
Pseudomonas Denitrificans ◽  
Factors Influencing ◽  
Vitamin Production

The effect of known precursors and cofactors on vitamin B12 production has been studied in a basal, chemically defined medium composed of sucrose, glutamic acid, and mineral salts. Only a carbon source, betaine, and Co2+ were found to be essential for vitamin B12 production. Known precursors such as methionine, δ-aminolevulinic acid, succinic acid, and 1-amino-2-propanol had no effect. Glycine was inhibitory to growth. Oxalic acid, lactic acid, 5,6-dimethylbenzimidazole, and Mo2+ stimulated vitamin B12 biosynthesis. Of special interest is oxalic acid, which at a level of 0.04% w/v increased vitamin production about 20%, and with washed cells could replace glutamic acid, which had been demonstrated to be essential for both growth and vitamin B12 production. When use of oxalate was followed, it was found that this acid disappeared during the period of rapid growth and vitamin production and then reappeared during the final stages of the fermentation cycle.

Requirements for growth of Pasteurella ureae in a chemically defined medium

1972 ◽  
Vol 18 (1) ◽  
pp. 107-109
Author(s):  
G. E. Wessman ◽  
Geraldine Wessman
Keyword(s):  
Amino Acids ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Defined Medium ◽  
Nutritional Requirements ◽  
Chemically Defined Medium

The nutritional requirements for culture of Pasteurella ureae in a chemically defined medium were determined. The medium in which the species grew best contained 16 amino acids: L-arginine, L-glutamic acid, L-alanine, and L-threonine were nutritionally essential; L-aspartic acid, L-leucine, and L-tryptophane were markedly stimulatory. The species also required uracil plus two purines, and two vitamins, nicotinamide and pantothenate.

Regulation of ammonia-assimilating enzymes by various nitrogen sources in cultured Ipomoea spp.

1989 ◽  
Vol 67 (11) ◽  
pp. 3127-3133 ◽  
Author(s):  
M. W. Zink
Keyword(s):  
Glutamine Synthetase ◽  
Glutamate Dehydrogenase ◽  
Growth Medium ◽  
Glutamate Synthase ◽  
Nitrogen Sources ◽  
Defined Medium ◽  
Morning Glory ◽  
Synthetase Activity ◽  
Glutamine Synthetase Activity ◽  
Chemically Defined Medium

The levels of ammonia-assimilating enzymes of Ipomoea spp. (morning glory) grown in suspension culture on a chemically defined medium are affected by various nitrogen sources. An increase in nitrate or ammonium concentrations in the growth medium elevated the levels of glutamate dehydrogenase, glutamine synthetase, and glutamate synthase. The levels of the enzymes varied in a manner similar to the growth pattern of the cells. When the growth rate of Ipomoea was maximal, high levels of enzymes were obtained; when cell growth was poor, a low yield of enzymes was obtained. Glutamine, whether used as the sole nitrogen source or as a supplement in media containing ammonium plus nitrate, increased the level of glutamate dehydrogenase and decreased the level of the other two enzymes. The developmental pattern of glutamine synthetase activity with culture age in Ipomoea differed with different nitrogen sources in the growth medium.

Improved cryopreservation of domestic cat sperm in a chemically defined medium

2012 ◽  
Vol 78 (9) ◽  
pp. 2120-2128 ◽  
Author(s):  
M.M. Vick ◽  
H.L. Bateman ◽  
C.A. Lambo ◽  
W.F. Swanson
Keyword(s):  
Defined Medium ◽  
Domestic Cat ◽  
Chemically Defined Medium
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