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Two copiotrophic Gram‐negative bacteria isolated from marine waters, S14 and Vibrio sp. DW1, were examined for changes in the rate of protein synthesis in the initial phase of energy and nutrient deprivation. The incorporation of [3H] leucine into the trichloroacetic acid (TCA)‐insoluble material was examined as a method for estimating rates of protein synthesis. The incorporation of methionine was measured and compared with the results of leucine incorporation. Protein synthesis was demonstrated throughout a period of 120 h of starvation. The incorporation rate was related to the time of starvation and decreased subsequent to an initial increase during the first few hours of dormancy. Control experiments with proteinase K and chloramphenicol demonstrated that the labelled amino acids were preferentially incorporated into proteins. It was also demonstrated that the uptake of amino acids was not a rate‐limiting step. During the first hours of starvation the ratio of the protein to the dry weight of the S14 cells increased parallel to the increase in the amino acid incorporation rate. The increased activity of the protein‐synthesising system during the first hours of nutrient and energy depletion indicates the presence of an active cellular response to the downshift conditions. Furthermore, these findings are consistent with the increased respiratory activity during the first hours of starvation, which has previously been observed for the bacteria examined in this study.

Extraction of lipids from bacterial cells or sewage sludge samples followed by simple and rapid extraction procedures and room temperature esterification with pentafluorobenzylbromide allowed combined determinations of poly-p-hydroxyalkanoate constituents and fatty acids. Capillary gas chromatography and flame ionization or mass spectrometric detection was used. Flame ionization permitted determination with a coefficient of variation ranging from 10 to 27% at the picomolar level, whereas quantitative chemical ionization mass spectrometry afforded sensitivities for poly-p-hydroxyalkanoate constituuents in the attomolar range. The latter technique suggests the possibility of measuring such components in bacterial assemblies with as few as 102 cells. With the described technique using flame ionization detection, it was possible to study the rapid formation of poly- ,-hydroxyalkanoate during feeding of a starved marine bacterium isolate with a complex medium or glucose and correlate the findings to changes in cell volumes. Mass spectrometric detection of short