ISSN:
1432-072X
Keywords:
Sulfate metabolism
;
Protein synthesis
;
Marine bacteria
;
Pseudomonas halodurans
;
Alteromonas luteo-violaceus
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Sulfate concentration in the growth medium exerted a strong influence on the sulfur content of protein in two marine bacteria, Pseudomonas halodurans and Alteromonasluteo-violaceus, but the distribution of sulfur in major biochemical fractions was not affected. 90% of the total cellular sulfur was contained in low molecular weight organic compounds and protein; inorganic sulfate was not an important component. The sulfur content of isolated protein and total cellular sulfur increased in proportion to the external sulfate concentration for both bacteria, reaching a maximum at about 100–250 μM. The growth rate of P. halodurans only was dependent on the sulfate concentration. Sulfur starvation of cells labeled to equilibrium with 35S-sulfate resulted in a rapid decrease in low molecular weight organic S with a concommitant increase in alcohol soluble (P. halodurans) or residue protein (A. luteo-violaceus). Although cell division was prevented, total protein increased in both bacteria, resulting in synthesis of sulfur-deficient protein. This effect was most pronounced in P. halodurans. Addition of 35S-sulfate to sulfur-starved A. luteo-violaceus further demonstrated that sulfur metabolism was restricted primarily to the synthesis and utilization of sulfurcontaining protein precursors. The low molecular weight organic S pool was replenished rapidly, and the pool size per cell reached twice the normal value before cell division resumed. Incorporation into protein was very rapid.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00527063
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