The search for guanosine tetraphosphate (ppGpp) and other unusual nucleotides in eucaryotes.

Assay of adenosine 5′-P1-tetraphospho-P4-5′′′-adenosine and adenosine 5′-P1-tetraphospho-P4-5′′′-guanosine in Physarum polycephalum and other eukaryotes. An isocratic high-pressure liquid-chromatography method

“…Dinucleoside polyphosphates other than Ap4A have been reported in connection with several areas of study. Several such compounds, including Gp4G, Gp3G, Gp3A and Gp2G, are constituents of the brine shrimp Artemia salina, and similar dinucleotides have been reported in related species [reviewed by Warner (1979) and Silverman & Atherly (1979)]. Gp4G is the major nucleotide in encysted embryos of A. salina and apparently serves as a reservoir for the synthesis of purine nucleotides during development (Warner, 1979).…”

Cellular nucleotide measurements and applications in microbial ecology.

“…The overwhelming majority of the published data have emphasized ATP concentrations (in terms of nanomoles of ATP per milligram [dry weight] of protein or cell N) and adenine nucleotide concentration ratios (i.e., ATP/ADP, ATP/AMP, or ECA) in bacteria and, to a lesser extent, in eucaryotes. A discussion of the occurrence and probable significance of cAMP, cyclic guanosine 3',5'-monophosphate, guanosine tetraphosphate, and other less abundant nucleotides in microbial cells is beyond the scope of this review; however, excellent current summaries of the distribution of guanosine tetraphsphate (292), cyclic guanosine 3',5'-monophosphate (113), and cAMP (270) and their involvement in metabolic regulation in microbial cells have appeared recently.…”

Cyclic nucleotides in procaryotes.

“…However, the rates of synthesis of the nucleotide were much lower when cells grew in chemostats then when cells grew in batch culture. It has been proposed that when cells grow under these conditions, energy is limiting and the cells can- Guanosine Tetraphosphate and cAMP Metabolism cAMP and guanosine 3',5'-bis-pyrophosphate (ppGpp) are both unusual nucleotides involved in control of a number of activities (27,63,237). The intracellular levels of both nucleotides are generally inversely proportional to the growth rate.…”