EurekaMag.com logo
+ Site Statistics
References:
48,253,228
Abstracts:
22,798,842
+ Resolve Accession
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
EurekaMag PDF Full Text Supply ServicePDF Full Text Supply Service
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
Submit PDF Full TextSubmit PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn
Follow on LinkedInFollow on Tumblr

+ Translate

Regulation of glutamine synthetase, aspartokinase, and total protein turnover in Klebsiella aerogenes


, : Regulation of glutamine synthetase, aspartokinase, and total protein turnover in Klebsiella aerogenes. Biochimica et Biophysica Acta 843(3): 214-229

When suspensions of Klebsiella aerogenes are incubated in a nitrogen-free medium there is a gradual decrease in the levels of acid-precipitable protein and of aspartokinase III (lysine-sensitive) and aspartokinase I (threonine-sensitive) activities. In contrast, the level of glutamine synthetase increases slightly and then remains constant. Under these conditions, the glutamine synthetase and other proteins continue to be synthesized as judged by the incorporation of [14C]leucine into the acid-precipitable protein fraction and into protein precipitated by anti-glutamine synthetase antibodies, by the fact that growth-inhibiting concentrations of chloramphenicol also inhibit the incorporation of [14C]leucine into protein and into protein precipitated by anti-glutamine synthetase antibody, and by the fact that chloramphenicol leads to acceleration in the loss of aspartokinases I and III and promotes a net decrease in the level of glutamine synthetase and its cross-reactive protein. The loss of aspartokinases I and III in cell suspensions is stimulated by glucose and is inhibited by 2,4-dinitrophenol. Glucose also stimulates the loss of aspartokinases and glutamine synthetase in the presence of chloramphenicol. Cell-free extracts of K. aerogenes catalyze rapid inactivation of endogenous glutamine synthetase as well as exogenously added pure glutamine synthetase. This loss of glutamine synthetase is not associated with a loss of protein that cross-reacts with anti-glutamine synthetase antibodies. The inactivation of glutamine synthetase in extracts is not due to adenylylation. It is partially prevented by sulfhydryl reagents, Mn2+, antimycin A, 2,4-dinitrophenol, EDTA, anaerobiosis and by dialysis. Following 18 h dialysis, the capacity of extracts to catalyze inactivation of glutamine synthetase is lost but can be restored by the addition of Fe2+ (or Ni2+) together with ATP (or other nucleoside di- and triphosphates. After 40-60 h dialysis Fe3+ together with NADH (but not ATP) are required for glutamine synthetase inactivation. The results suggest that accelerated protein degradation in cells exposed to nitrogen-limited conditions reflects the differential destruction of some proteins, including aspartokinases I and III, in order to sustain the biosynthesis of others such as glutamine synthetase. The loss of glutamine synthetase activity in cell-free extracts is likely mediated in part by mixed-function oxidation systems and could represent a 'marking' step in protein turnover.

(PDF 0-2 workdays service)

Order PDF Full Text

Close
Close

Click here to order any other PDF Full Text


Accession: 041210765

PMID: 2865982

PDF Full Text: Submit


Submit PDF Full Text

No spam - Every submission is manually reviewed

Due to poor quality, we do not accept files from Researchgate

Submitted PDF Full Texts will always be free for everyone
(We only charge for PDFs that we need to acquire)

Select a PDF file:
Close
Close

Other references

De Raeve, H.; Schoonooghe, P.; Wibowo, R.; Van Marck, E.; Goossens, A., 2003: Malignant large cell calcifying Sertoli cell tumor of the testis. A 45-year old man presented with a slow-growing, unilateral beige testicular mass, with a diameter of 4 cm. The testosterone, FSH, LH, estradiol and betahCG serum levels were within normal limits, and there were no associated hormonal syndromes. T...

Samant, S. S.; Joshi, H. C., 2005: Plant diversity and conservation status of Nanda Devi National Park and comparison with highland National Parks of the Indian Himalayan Region. This paper addresses the plant diversity and conservation status of Nanda Devi National Park (NDNP) and compares these with the Valley of Flowers National Park (VOFNP) and Great Himalayan National Park (GHNP), India. In the NDNP, 490 species belon...

Copeland, P.M.; Martin, J.B.; Ridgway, E.C., 1986: Cysteamine decreases prolactin responsiveness to thyrotropin-releasing hormone in normal men. Cysteamine depletes pituitary and plasma prolactin in rats. It acts through a nondopaminergic mechanism to alter both immunoactive and bioactive prolactin. The effect of cysteamine on prolactin secretion is reported in normal men. Six normal subje...

Lukashevich, N. P., 1986: Producing new initial material from crosses of ecologically and geographically distant forms in the breeding of spring triticale. A study of hybrids from crosses of ecologically diverse forms in the Byelorussian SSR revealed the nature of the inheritance of the basic quantitative traits. The best lines, which exceeded the spring wheat Leningradka in yield, were selected and...

Walsh, David J., 2000: Intubation of lacrimal ducts. The invention provides a probe set having at least one probe of a light wire which can be resiliently deflected to pass from the nasolacrimal duct to the nasal inferior meatus. The probe has an enlarged and rounded distal end portion to limit the...

Hackman, R.M.; Ellis, B.K.; Brown, R.L., 1994: Phosphorus magnetic resonance spectra and changes in body composition during weight loss. Objective: The use of magnetic resonance spectroscopy (MRS) to monitor cellular bioenergetics during weight loss may provide novel insights regarding metabolic functioning. Methods: Changes were noted in 18 sedentary, moderately overweight women f...

Niedzielska, B., 1989: Analysis of macroscopic structure and wood density of silver fir (Abies alba Mill.) originating from the natural distributional range in Poland. Data are reported from 35 sample areas in typical silver fir associations and habitat types. Clear differentiation of wood characteristics was observed from east to west.

McIntosh, A. J., 1999: Into the tourist's mind: understanding the value of the heritage experience. The individual consumer of heritage has, up until recently, been neglected in much heritage management. The heritage visitor is nevertheless, an important evaluator of the service experience being provided at cultural heritage attractions. A surve...

Nicholson K.G.; Ali S.; Burney M.I.; Perkins F.T., 1983: Stability of human di ploid cell strain rabies vaccine at high ambient temperatures. A batch of lyophilized human diploid-cell-strain rabies vaccine was divided into 3 batches, which were exposed to different temperatures during their distribution to and storage at 3 centers in Pakistan. Vaccine potency after exposure to these tem...

Cammarano Fabio; Goes Saskia; Vacher Pierre; Giardini Domenico, 2003: Inferring upper-mantle temperatures from seismic velocities. Constraints on mantle temperatures are fundamental for a better understanding of the dynamics of the Earth. We evaluate how well upper-mantle thermal structure can be inferred from seismic velocities. Our forward calculation of seismic velocities...