The intracellular Na+ and K+ composition of the moderately halophilic bacterium, Paracoccus halodenitrificans

1980 ◽  
Vol 26 (4) ◽  
pp. 496-502 ◽  
Author(s):  
M. Sadler ◽  
M. McAninch ◽  
R. Alico ◽  
L. I. Hochstein
Keyword(s):  
Stationary Phase ◽  
Growth Medium ◽  
Nadh Oxidase ◽  
Halophilic Bacterium ◽  
Oxidase System ◽  
Final Value ◽  
Moderately Halophilic Bacterium ◽  
Nacl Concentration ◽  
Atp Pool ◽  
Membrane Bound

The intracellular concentrations of Na+ and K+ in exponentially growing Paracoccus halodenitrificans were independent of the NaCl concentration of the growth medium. The observed values were approximately 100 and 300 mM for Na+ and K+, respectively. In stationary phase cells, the ultimate values for Na+ depended on the NaCl concentration of the growth medium. With cells grown in the presence of 1 M NaCl, the value was about 500 mM; for cells grown in the presence of 3 M NaCl, the value was about 1.1 M. The K+ concentration in stationary phase cells was unaffected by the NaCl concentration in the growth medium. The final value was about 100 mM. Associated with these changes were changes in the ATP pool and decreases in the activities of the NADH oxidase system and the membrane-bound ATPase. It is proposed that the decrease in the activities of these enzymes may account for the ion flows observed in stationary phase cells.

scholarly journals Synthesis of Glycine Betaine from Exogenous Choline in the Moderately Halophilic Bacterium Halomonas elongata

1998 ◽  
Vol 64 (10) ◽  
pp. 4095-4097 ◽  
Author(s):  
David Cánovas ◽  
Carmen Vargas ◽  
Laszlo N. Csonka ◽  
Antonio Ventosa ◽  
Joaquín J. Nieto
Keyword(s):  
Growth Medium ◽  
Glycine Betaine ◽  
Halophilic Bacterium ◽  
Intracellular Accumulation ◽  
Moderate Halophile ◽  
Moderately Halophilic ◽  
Moderately Halophilic Bacterium ◽  
Halomonas Elongata ◽  
Nacl Concentration

ABSTRACT The role of choline in osmoprotection in the moderate halophileHalomonas elongata has been examined. Transport and conversion of choline to betaine began immediately after addition of choline to the growth medium. Intracellular accumulation of betaine synthesized from choline was salt dependent up to 2.5 M NaCl. Oxidation of choline was enhanced at 2.0 M NaCl in the presence or absence of externally provided betaine. This indicates that the NaCl concentration in the growth medium has major effects on the choline-betaine pathway of H. elongata.

Protein turnover in a moderately halophilic bacterium

1980 ◽  
Vol 26 (2) ◽  
pp. 196-203 ◽  
Author(s):  
A. R. Hipkiss ◽  
D. W. Armstrong ◽  
D. J. Kushner
Keyword(s):  
Protein Turnover ◽  
Critical Factor ◽  
Optimal Growth ◽  
Halophilic Bacterium ◽  
High Rate ◽  
Breakdown Rate ◽  
Intact Cells ◽  
Moderately Halophilic ◽  
Moderately Halophilic Bacterium ◽  
Nacl Concentration

Protein turnover was investigated in exponentially growing Vibrio costicola, a moderately halophilic bacterium that can grow in the NaCl concentration range 0.5–3.5 M (with optimal growth at about 1.0 M). In 1.0 or 1.5 M NaCl the breakdown rate of pulse-labelled proteins was about 5%/h whereas in 0.5 M NaCl breakdown was about 9%/h. These results are in contrast to those reported and observed in Escherichia coli which has a turnover rate of 1–2%/h in exponential growth. Growing E. coli in the highest possible NaCl concentration (1.0 M) did not significantly increase protein turnover. Shifting V. costicola from a higher to a lower NaCl concentration increased the rate of turnover of pulse-labelled proteins, whereas shifting it from a lower to a higher NaCl concentration decreased the rate of turnover. The critical factor in these experiments was not the NaCl concentration at which proteins were labelled but that at which the cells were subsequently incubated. The level of breakdown of long-labelled proteins was low (about 2%/h) and was not affected by shifts in NaCl concentration. Breakdown of pulse-labelled protein was inhibited by cyanide and tetracycline but not by iodoacetate, azide. or chloramphenicol. Treatment with streptomycin increased the rate of turnover. Turnover in cell-free systems was lower than in intact cells and was not inhibited by cyanide or tetracycline. It is suggested that the high rate of turnover, even at optimal NaCl concentrations, may reflect errors in protein synthesis, and that the effect of lower NaCl concentrations may be to alter "native" conformation and thus to increase the susceptibility of some of the properly made proteins to proteolysis.

scholarly journals Streptohalobacillus salinus gen. nov., sp. nov., a moderately halophilic, Gram-positive, facultative anaerobe isolated from subsurface saline soil

2011 ◽  
Vol 61 (5) ◽  
pp. 1127-1132 ◽  
Author(s):  
Xiaowei Wang ◽  
Yanfen Xue ◽  
Yanhe Ma
Keyword(s):  
Saline Soil ◽  
Qaidam Basin ◽  
Halophilic Bacterium ◽  
Diaminopimelic Acid ◽  
Rrna Gene ◽  
16S Rrna Gene Sequences ◽  
Moderately Halophilic ◽  
Moderately Halophilic Bacterium ◽  
The Family ◽  
Diamino Acid

A Gram-stain-positive, rod-shaped, non-sporulating, motile and moderately halophilic bacterium, designated strain H96B60T, was isolated from a saline soil sample of the Qaidam basin, China. The strain was facultatively anaerobic. Major end products formed from glucose fermentation were acetate, ethanol and lactic acid. The cell-wall peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. The isoprenoid quinone component was menaquinone-6 (MK-6). The predominant cellular fatty acids were C16 : 0, anteiso-C13 : 0 and anteiso-C15 : 0. The genomic DNA G+C content of strain H96B60T was 36.2 mol%. Phylogenetic analysis based on comparative 16S rRNA gene sequences indicated that strain H96B60T represented a novel phyletic lineage within the family Bacillaceae and was related most closely to Halolactibacillus species (96.1–96.4 % similarity). Based on the phenotypic, chemotaxonomic and phylogenetic data presented, strain H96B60T is considered to represent a novel species of a new genus, for which the name Streptohalobacillus salinus gen. nov., sp. nov. is proposed. The type strain of Streptohalobacillus salinus is H96B60T ( = DSM 22440T  = CGMCC 1.7733T).

NADH oxidase system of Agrobacterium tumefaciens

1966 ◽  
Vol 113 (3) ◽  
pp. 548-553 ◽  
Author(s):  
C.K.Ramakrishna Kurup ◽  
C.S. Vaidyanathan ◽  
T. Ramasarma
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Nadh Oxidase ◽  
Oxidase System
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