Enzymes du métabolisme des polyphosphates dans la levure

Felter, S.; Stahl, A

doi:10.1016/s0300-9084(73)80122-1

Cited by 35 publications

(3 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…ATP + polyP(s) -ADP + polyP(n + 1) where polyP is polyphosphate and n is the degree of polymerization. The activity was first demonstrated in yeast cell extracts by Yoshida and Yamataka (38), and the enzyme has subsequently been purified to a greater or lesser extent from a number of microorganisms, namely; Escherichia coli (1,18,22), Corynebacterium xerosis (25), Salmonella minnesota (26), Saccharomyces cerevisiae (8), Propionibacterium shermanii (31,32), and Sulfolobus acidocaldarius (33).…”

mentioning

confidence: 99%

Purification and characterization of polyphosphate kinase from Neisseria meningitidis

1993

View full text Add to dashboard Cite

The important human pathogens Neisseria meningitidis and Neisseria gonorrhoeae accumulate phosphate in the form of polyphosphate (A. Noegel and E. C. Gotschlich, J. Exp. Med. 157:2049-2060, 1983), and the localization of more than half of this long-chain polymer on the exterior of the cells suggests a function as a protective, capsule-like coating. To enable further genetic investigation of the role of polyphosphate in Neisseria spp., the enzyme polyphosphate kinase (PPK), which catalyzes the synthesis of polyphosphate from ATP, was purified from N. meningitidis BNCV. The activity is dependent on Mg2+ and phosphate or polyphosphate and is inhibited by ADP. The Km for ATP is 1.5 mM, and the turnover number is 47 phosphate residues per polypeptide per s. Analysis of PPK labelled with [gamma-32P]ATP indicates that the enzyme is phosphorylated during the reaction, probably at an arginine residue. N-terminal and two internal amino acid sequences were derived from the purified protein and will allow the design of synthetic oligonucleotides for cloning and genetic manipulation of the ppk gene.

show abstract

mentioning

confidence: 99%

Purification and characterization of polyphosphate kinase from Neisseria meningitidis

1993

View full text Add to dashboard Cite

show abstract

“…The fact that the phosphate bonds are high energy has prompted many researchers to suggest that polyphosphate acts as a phosphogen or energy store (23). Other groups have suggested that polyphosphate is the preferred substrate for the hexokinase reaction (24); some indicate that polyphosphate is most importantly a phosphate store to be used during phosphate deprivation (25).…”

mentioning

confidence: 99%

31P NMR studies of intracellular pH and phosphate metabolism during cell division cycle of Saccharomyces cerevisiae.

Gillies¹,

Uğurbil²,

Hollander³

et al. 1981

Proc. Natl. Acad. Sci. U.S.A.

118

View full text Add to dashboard Cite

We have analyzed changes in intracellular pH and phosphate metabolism during the cell cycle of Saccharomyces cerevisiae (NCYC 239) by using high-resolution 31P NMR spectroscopy. High-density yeast cultures (2 x 108 cells per ml) were arrested prior to "start" by sequential glucose deprivation, after which they synchronously replicated DNA and divided after a final glucose feeding. Oxygenation of arrested cultures in the absence ofglucose led to increased levels ofsugar phosphates and ATP and an increase in intracellular pH. However, these conditions did not initiate cell cycle progression, indicating that energization is not used as an intracellular signal for initiation ofthe cell division cycle and that the cells need exogenous carbon sources for growth. Glucose refeeding initiated an alkaline intracellular pH transient only in the synchronous cultures, showing that increased intracellular pH accompanies the traversal of start. Changes in phosphate flow and utilization also were observed in the synchronous cultures. In particular, there was increased consumption of external phosphate during DNA synthesis. When external phosphate levels were low, the cells consumed their internal polyphosphate stores. This shows that, under these conditions, polyphosphate acts as a phosphate supply. 31P NMR spectroscopy is rapidly gaining in importance as a technique for the noninvasive analysis ofphosphorus-containing metabolites and intracellular pH in vivo. Since the first 31p NMR spectra ofyeast were published in 1975 (1), sensitivity and resolution have been improved to allow for the investigation of glycolytic mutants (2), the control of glycolysis (3), and compartmentation of pH in ascospores (4). In this communication, we present the results of a 31P NMR analysis of synchronous suspensions of yeast cells in which we have investigated intracellular pH and phosphorus metabolism during the cell division cycle.Yeast are an ideal system for investigating the cell division cycle. We have found that they can be maintained for long periods at the high densities (2 x 108 cells per ml) necessary to obtain good signal-to-noise in the NMR experiments. In addition, many temperature-sensitive cell division cycle mutants of Saccharomyces cerevisiae are available, allowing for more detailed analyses in the future.Concepts of the cell division cycle in yeast have changed in recent years. Using the cell division cycle mutant system, Hartwell and his colleagues (5-10) have identified the presence of two loosely coupled subcycles, each comprising a series of discrete, interdependent steps. One subcycle involves the nuclear events of DNA replication and nuclear division; the other consists of the cytoplasmic events governing bud emergence and growth. The subcycles converge prior to mitosis and diverge again after a point called "start"; this point bears some similarity to the R point ofmammalian cells (11). Although much is known with regard to the morphologic and genetic aspects of "start," its biochemistry is relatively unknown. ...

show abstract

“…Their physiological function, however, remains ill-defined. Besides the possibility that polyphosphates might reFresent a form of energy storage [2], they are more often believed to participate in the regulation of the intracellular [Pi] by constituting a phosphorus reserve [3]. Their metabolism appears rather complex and has been more extensively studied in bacterial species such asAerobacteraerogenes [4,5] or Corynebacterium xerosis [6], in which these compounds substantially accumulate.…”

Section: Introductionmentioning

confidence: 99%

Is the acid phosphatase of Escherichia coli with pH optimum of 2.5 a polyphosphate depolymerase?

Dassa

Boquet

1981

FEBS Letters

View full text Add to dashboard Cite

Enzymes du métabolisme des polyphosphates dans la levure

Cited by 35 publications

References 6 publications

Purification and characterization of polyphosphate kinase from Neisseria meningitidis

Purification and characterization of polyphosphate kinase from Neisseria meningitidis

31P NMR studies of intracellular pH and phosphate metabolism during cell division cycle of Saccharomyces cerevisiae.

Is the acid phosphatase of Escherichia coli with pH optimum of 2.5 a polyphosphate depolymerase?

Contact Info

Product

Resources

About